Release v2.1.3

Fix SafeERC20.safeApprove bug

(cherry picked from commit 3111291b4a)

.env.example

@@ -1,5 +0,0 @@
-# configure your infura api key (not technically required)
-INFURA_API_KEY=
-
-# change the mnemonic that your hd wallet is seeded with
-MNEMONIC=

.eslintrc

@@ -1,22 +1,23 @@
 {
   "extends" : [
     "standard",
-    "plugin:promise/recommended"
+    "plugin:promise/recommended",
   ],
   "plugins": [
-    "promise"
+    "mocha-no-only",
+    "promise",
   ],
   "env": {
     "browser" : true,
     "node"    : true,
     "mocha"   : true,
-    "jest"    : true
+    "jest"    : true,
   },
   "globals" : {
     "artifacts": false,
     "contract": false,
     "assert": false,
-    "web3": false
+    "web3": false,
   },
   "rules": {
 
@@ -49,6 +50,8 @@
     "semi": ["error", "always"],
     "space-before-function-paren": ["error", "always"],
 
+    "mocha-no-only/mocha-no-only": ["error"],
+
     "promise/always-return": "off",
     "promise/avoid-new": "off",
   }

.github/ISSUE_TEMPLATE.md

@@ -1,34 +0,0 @@
-## 🎉 Description
-
-<!-- Briefly describe the issue you are experiencing (or the feature you want to see added to OpenZeppelin). Tell us what you were trying to do and what happened instead. **Remember, this is _not_ a place to ask for help debugging code; for that, we welcome you in the [OpenZeppelin Slack Channel](https://slack.openzeppelin.org/).** -->
-
-- [ ] 🐛 This is a bug report.
-- [ ] 📈 This is a feature request.
-
-<!-- Please check one of the above by placing an x in the box. -->
-
-## 💻 Environment
-
-Next, we need to know what your environment looks like.
-
-- Which version of OpenZeppelin are you using?
-- What network are you deploying to? Ganache? Ropsten?
-- How are you deploying your OpenZeppelin-backed contracts? truffle? Remix? Let us know!
-
-## 📝 Details
-
-Describe the problem you have been experiencing in more detail. Include as much information as you think is relevant. Keep in mind that transactions can fail for many reasons; context is key here.
-
-## 🔢 Code To Reproduce Issue [ Good To Have ]
-
-Please remember that with sample code it's easier to reproduce the bug and it's much faster to fix it.
-
-```
-insert short code snippets here
-```
-
-<!-- If your code is larger, consider linking us to a repo illustrating your issue. -->
-
-## 👍 Other Information
-
-<!-- List any other information that is relevant to your issue. Error logs, related issues, suggestions on how to fix, Stack Overflow links, forum links, etc. -->

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,21 @@
+---
+name: Bug report
+about: Report a bug in OpenZeppelin
+
+---
+
+<!-- Briefly describe the issue you're experiencing. Tell us what you were trying to do and what happened instead. -->
+
+<!-- Remember, this is not a place to ask for help debugging code. For that, we welcome you in the OpenZeppelin Slack channel: https://slack.openzeppelin.org/. -->
+
+**💻 Environment**
+
+<!-- Tell us what version of OpenZeppelin you're using, and how you're using it: Truffle, Remix, etc. -->
+
+**📝 Details**
+
+<!-- Describe the problem you have been experiencing in more detail. Include as much information as you think is relevant. Keep in mind that transactions can fail for many reasons; context is key here. -->
+
+**🔢 Code to reproduce bug**
+
+<!-- We will be able to better help if you provide a minimal example that triggers the bug. -->

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,14 @@
+---
+name: Feature request
+about: Suggest an idea for OpenZeppelin
+
+---
+
+**🧐 Motivation**
+<!-- Is your feature request related to a specific problem? Is it just a crazy idea? Tell us about it! -->
+
+**📝 Details**
+<!-- Please describe your feature request in detail. -->
+
+<!-- Make sure that you have reviewed the OpenZeppelin Contributor Guidelines. -->
+<!-- https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/CONTRIBUTING.md -->

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,17 +1,21 @@
 <!-- 0. 🎉 Thank you for submitting a PR! -->
 
-<!-- 1. **Does this close any open issues?** If so, list them here. If not, remove the `Fixes #` line. -->
+<!-- 1. Does this close any open issues? Please list them below. -->
+
+<!-- Keep in mind that new features have a better chance of being merged fast if
+they were first discussed and designed with the maintainers. If there is no
+corresponding issue, please consider opening one for discussion first! -->
 
 Fixes #
 
-# 🚀 Description
+<!-- 2. Describe the changes introduced in this pull request. -->
-
-<!-- 2. Describe the changes introduced in this pull request -->
 <!--    Include any context necessary for understanding the PR's purpose. -->
 
-<!-- 3. Before submitting, please review the following checklist: -->
+<!-- 3. Before submitting, please make sure that you have:
-
+  - reviewed the OpenZeppelin Contributor Guidelines
-- [ ] 📘 I've reviewed the [OpenZeppelin Contributor Guidelines](../blob/master/CONTRIBUTING.md)
+    (https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/CONTRIBUTING.md),
-- [ ] ✅ I've added tests where applicable to test my new functionality.
+  - added tests where applicable to test new functionality,
-- [ ] 📖 I've made sure that my contracts are well-documented.
+  - made sure that your contracts are well-documented,
-- [ ] 🎨 I've run the JS/Solidity linters and fixed any issues (`npm run lint:fix`).
+  - run the JS/Solidity linters and fixed any issues (`npm run lint:fix`), and
+  - updated the changelog, if applicable.
+-->

.solhint.json

@@ -0,0 +1,11 @@
+{
+  "extends": "default",
+  "rules": {
+    "indent": ["error", 4],
+
+    "bracket-align": false,
+    "compiler-fixed": false,
+    "no-simple-event-func-name": false,
+    "two-lines-top-level-separator": false
+  }
+}

.soliumignore

@@ -1 +0,0 @@
-node_modules

.soliumrc.json

@@ -1,21 +0,0 @@
-{
-  "extends": "solium:all",
-  "plugins": ["security"],
-  "rules": {
-    "blank-lines": "off",
-    "error-reason": "off",
-    "indentation": ["error", 2],
-    "lbrace": "off",
-    "linebreak-style": ["error", "unix"],
-    "max-len": ["error", 79],
-    "no-constant": ["error"],
-    "no-empty-blocks": "off",
-    "quotes": ["error", "double"],
-    "uppercase": "off",
-    "visibility-first": "error",
-
-    "security/enforce-explicit-visibility": ["error"],
-    "security/no-block-members": ["warning"],
-    "security/no-inline-assembly": ["warning"]
-  }
-}

.travis.yml

@@ -15,29 +15,27 @@ jobs:
   # --elopio - 20180531
   fast_finish: true
   allow_failures:
-    - env: SOLIDITY_COVERAGE=true
     - env: SOLC_NIGHTLY=true
   include:
-    # Run the unit test suite three times in parallel.
-    # The first one gets results faster and is the only one required to pass.
-    # The second one generates the coverage report.
-    # The third one is to keep us informed about possible issues with the
-    # upcoming solidity release.
     - stage: tests
-      name: "unit tests"
+      name: "Linter"
+      script: npm run lint
+
+    - stage: tests
+      name: "Unit tests"
       script: npm run test
+
+# solidity-coverage fails at parsing 0.5.x code
+#    - stage: tests
+#      name: "Unit tests with coverage report"
+#      script: npm run test
+#      env: SOLIDITY_COVERAGE=true
+
     - stage: tests
-      name: "unit tests with coverage"
+      name: "Unit tests using solc nightly"
-      script: npm run test
-      env: SOLIDITY_COVERAGE=true
-    - stage: tests
-      name: "unit tests with solc nightly"
       script: npm run test
       env: SOLC_NIGHTLY=true
-    # solidity and javascript style tests.
+
-    - stage: tests
-      name: "static tests"
-      script: npm run lint
     - stage: update docs
       if: tag =~ ^v[0-9]+\.[0-9]+\.[0-9]+$
       addons:

CHANGELOG.md

@@ -0,0 +1,40 @@
+# Changelog
+
+## 2.2.0 (unreleased)
+
+## 2.1.3 (2019-26-02)
+ * Backported `SafeERC20.safeApprove` bugfix. ([#1647](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1647))
+
+## 2.1.2 (2019-17-01)
+ * Removed most of the test suite from the npm package, except `PublicRole.behavior.js`, which may be useful to users testing their own `Roles`.
+
+## 2.1.1 (2019-04-01)
+ * Version bump to avoid conflict in the npm registry.
+
+## 2.1.0 (2019-04-01)
+
+### New features:
+ * Now targeting the 0.5.x line of Solidity compilers. For 0.4.24 support, use version 2.0 of OpenZeppelin.
+ * `WhitelistCrowdsale`: a crowdsale where only whitelisted accounts (`WhitelistedRole`) can purchase tokens. Adding or removing accounts from the whitelist is done by whitelist admins (`WhitelistAdminRole`). Similar to the pre-2.0 `WhitelistedCrowdsale`. ([#1525](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1525), [#1589](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1589))
+ * `RefundablePostDeliveryCrowdsale`: replacement for `RefundableCrowdsale` (deprecated, see below) where tokens are only granted once the crowdsale ends (if it meets its goal). ([#1543](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1543))
+ * `PausableCrowdsale`: allows for pausers (`PauserRole`) to pause token purchases. Other crowdsale operations (e.g. withdrawals and refunds, if applicable) are not affected. ([#832](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/832))
+ * `ERC20`: `transferFrom` and `_burnFrom ` now emit `Approval` events, to represent the token's state comprehensively through events. ([#1524](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1524))
+ * `ERC721`: added `_burn(uint256 tokenId)`, replacing the similar deprecated function (see below). ([#1550](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1550))
+ * `ERC721`: added `_tokensOfOwner(address owner)`, allowing to internally retrieve the array of an account's owned tokens. ([#1522](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1522))
+ * Crowdsales: all constructors are now `public`, meaning it is not necessary to extend these contracts in order to deploy them. The exception is `FinalizableCrowdsale`, since it is meaningless unless extended. ([#1564](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1564))
+ * `SignedSafeMath`: added overflow-safe operations for signed integers (`int256`). ([#1559](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1559), [#1588](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1588))
+
+### Improvements:
+ * The compiler version required by `Array` was behind the rest of the libray so it was updated to `v0.4.24`. ([#1553](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1553))
+ * Now conforming to a 4-space indentation code style. ([1508](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1508))
+ * `ERC20`: more gas efficient due to removed redundant `require`s. ([#1409](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1409))
+ * `ERC721`: fixed a bug that prevented internal data structures from being properly cleaned, missing potential gas refunds. ([#1539](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1539) and [#1549](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1549))
+ * `ERC721`: general gas savings on `transferFrom`, `_mint` and `_burn`, due to redudant `require`s and `SSTORE`s. ([#1549](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1549))
+
+### Bugfixes:
+
+### Breaking changes:
+
+### Deprecations:
+ * `ERC721._burn(address owner, uint256 tokenId)`: due to the `owner` parameter being unnecessary. ([#1550](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1550))
+ * `RefundableCrowdsale`: due to trading abuse potential on crowdsales that miss their goal. ([#1543](https://github.com/OpenZeppelin/openzeppelin-solidity/pull/1543))

README.md

@@ -1,8 +1,8 @@
 # <img src="logo.png" alt="OpenZeppelin" width="400px">
 
 [![NPM Package](https://img.shields.io/npm/v/openzeppelin-solidity.svg?style=flat-square)](https://www.npmjs.org/package/openzeppelin-solidity)
-[![Build Status](https://img.shields.io/travis/OpenZeppelin/openzeppelin-solidity.svg?branch=master&style=flat-square)](https://travis-ci.org/OpenZeppelin/openzeppelin-solidity)
+[![Build Status](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity.svg?branch=master)](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity)
-[![Coverage Status](https://img.shields.io/coveralls/github/OpenZeppelin/openzeppelin-solidity/master.svg?style=flat-square)](https://coveralls.io/github/OpenZeppelin/openzeppelin-solidity?branch=master)
+[![Coverage Status](https://coveralls.io/repos/github/OpenZeppelin/openzeppelin-solidity/badge.svg?branch=master)](https://coveralls.io/github/OpenZeppelin/openzeppelin-solidity?branch=master)
 
 **OpenZeppelin is a library for secure smart contract development.** It provides implementations of standards like ERC20 and ERC721 which you can deploy as-is or extend to suit your needs, as well as Solidity components to build custom contracts and more complex decentralized systems.
 

RELEASING.md

@@ -34,7 +34,7 @@ git push upstream vX.Y.Z-rc.R
 
 Draft the release notes in our [GitHub releases](https://github.com/OpenZeppelin/openzeppelin-solidity/releases). Make sure to mark it as a pre-release! Try to be consistent with our previous release notes in the title and format of the text. Release candidates don't need a detailed changelog, but make sure to include a link to GitHub's compare page.
 
-Once the CI run for the new tag is green, publish on npm under the `next` tag.
+Once the CI run for the new tag is green, publish on npm under the `next` tag. You should see the contracts compile automatically.
 
 ```
 npm publish --tag next
@@ -62,7 +62,7 @@ git push upstream vX.Y.Z
 
 Draft the release notes in GitHub releases. Try to be consistent with our previous release notes in the title and format of the text. Make sure to include a detailed changelog.
 
-Once the CI run for the new tag is green, publish on npm.
+Once the CI run for the new tag is green, publish on npm. You should see the contracts compile automatically.
 
 ```
 npm publish

contracts/access/Roles.sol

@@ -1,44 +1,40 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title Roles
  * @dev Library for managing addresses assigned to a Role.
  */
 library Roles {
-  struct Role {
+    struct Role {
-    mapping (address => bool) bearer;
+        mapping (address => bool) bearer;
-  }
+    }
 
-  /**
+    /**
-   * @dev give an account access to this role
+     * @dev give an account access to this role
-   */
+     */
-  function add(Role storage role, address account) internal {
+    function add(Role storage role, address account) internal {
-    require(account != address(0));
+        require(account != address(0));
-    require(!has(role, account));
+        require(!has(role, account));
 
-    role.bearer[account] = true;
+        role.bearer[account] = true;
-  }
+    }
 
-  /**
+    /**
-   * @dev remove an account's access to this role
+     * @dev remove an account's access to this role
-   */
+     */
-  function remove(Role storage role, address account) internal {
+    function remove(Role storage role, address account) internal {
-    require(account != address(0));
+        require(account != address(0));
-    require(has(role, account));
+        require(has(role, account));
 
-    role.bearer[account] = false;
+        role.bearer[account] = false;
-  }
+    }
 
-  /**
+    /**
-   * @dev check if an account has this role
+     * @dev check if an account has this role
-   * @return bool
+     * @return bool
-   */
+     */
-  function has(Role storage role, address account)
+    function has(Role storage role, address account) internal view returns (bool) {
-    internal
+        require(account != address(0));
-    view
+        return role.bearer[account];
-    returns (bool)
+    }
-  {
-    require(account != address(0));
-    return role.bearer[account];
-  }
 }

contracts/access/roles/CapperRole.sol

@@ -1,43 +1,43 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Roles.sol";
 
 contract CapperRole {
-  using Roles for Roles.Role;
+    using Roles for Roles.Role;
 
-  event CapperAdded(address indexed account);
+    event CapperAdded(address indexed account);
-  event CapperRemoved(address indexed account);
+    event CapperRemoved(address indexed account);
 
-  Roles.Role private cappers;
+    Roles.Role private _cappers;
 
-  constructor() internal {
+    constructor () internal {
-    _addCapper(msg.sender);
+        _addCapper(msg.sender);
-  }
+    }
 
-  modifier onlyCapper() {
+    modifier onlyCapper() {
-    require(isCapper(msg.sender));
+        require(isCapper(msg.sender));
-    _;
+        _;
-  }
+    }
 
-  function isCapper(address account) public view returns (bool) {
+    function isCapper(address account) public view returns (bool) {
-    return cappers.has(account);
+        return _cappers.has(account);
-  }
+    }
 
-  function addCapper(address account) public onlyCapper {
+    function addCapper(address account) public onlyCapper {
-    _addCapper(account);
+        _addCapper(account);
-  }
+    }
 
-  function renounceCapper() public {
+    function renounceCapper() public {
-    _removeCapper(msg.sender);
+        _removeCapper(msg.sender);
-  }
+    }
 
-  function _addCapper(address account) internal {
+    function _addCapper(address account) internal {
-    cappers.add(account);
+        _cappers.add(account);
-    emit CapperAdded(account);
+        emit CapperAdded(account);
-  }
+    }
 
-  function _removeCapper(address account) internal {
+    function _removeCapper(address account) internal {
-    cappers.remove(account);
+        _cappers.remove(account);
-    emit CapperRemoved(account);
+        emit CapperRemoved(account);
-  }
+    }
 }

contracts/access/roles/MinterRole.sol

@@ -1,43 +1,43 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Roles.sol";
 
 contract MinterRole {
-  using Roles for Roles.Role;
+    using Roles for Roles.Role;
 
-  event MinterAdded(address indexed account);
+    event MinterAdded(address indexed account);
-  event MinterRemoved(address indexed account);
+    event MinterRemoved(address indexed account);
 
-  Roles.Role private minters;
+    Roles.Role private _minters;
 
-  constructor() internal {
+    constructor () internal {
-    _addMinter(msg.sender);
+        _addMinter(msg.sender);
-  }
+    }
 
-  modifier onlyMinter() {
+    modifier onlyMinter() {
-    require(isMinter(msg.sender));
+        require(isMinter(msg.sender));
-    _;
+        _;
-  }
+    }
 
-  function isMinter(address account) public view returns (bool) {
+    function isMinter(address account) public view returns (bool) {
-    return minters.has(account);
+        return _minters.has(account);
-  }
+    }
 
-  function addMinter(address account) public onlyMinter {
+    function addMinter(address account) public onlyMinter {
-    _addMinter(account);
+        _addMinter(account);
-  }
+    }
 
-  function renounceMinter() public {
+    function renounceMinter() public {
-    _removeMinter(msg.sender);
+        _removeMinter(msg.sender);
-  }
+    }
 
-  function _addMinter(address account) internal {
+    function _addMinter(address account) internal {
-    minters.add(account);
+        _minters.add(account);
-    emit MinterAdded(account);
+        emit MinterAdded(account);
-  }
+    }
 
-  function _removeMinter(address account) internal {
+    function _removeMinter(address account) internal {
-    minters.remove(account);
+        _minters.remove(account);
-    emit MinterRemoved(account);
+        emit MinterRemoved(account);
-  }
+    }
 }

contracts/access/roles/PauserRole.sol

@@ -1,43 +1,43 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Roles.sol";
 
 contract PauserRole {
-  using Roles for Roles.Role;
+    using Roles for Roles.Role;
 
-  event PauserAdded(address indexed account);
+    event PauserAdded(address indexed account);
-  event PauserRemoved(address indexed account);
+    event PauserRemoved(address indexed account);
 
-  Roles.Role private pausers;
+    Roles.Role private _pausers;
 
-  constructor() internal {
+    constructor () internal {
-    _addPauser(msg.sender);
+        _addPauser(msg.sender);
-  }
+    }
 
-  modifier onlyPauser() {
+    modifier onlyPauser() {
-    require(isPauser(msg.sender));
+        require(isPauser(msg.sender));
-    _;
+        _;
-  }
+    }
 
-  function isPauser(address account) public view returns (bool) {
+    function isPauser(address account) public view returns (bool) {
-    return pausers.has(account);
+        return _pausers.has(account);
-  }
+    }
 
-  function addPauser(address account) public onlyPauser {
+    function addPauser(address account) public onlyPauser {
-    _addPauser(account);
+        _addPauser(account);
-  }
+    }
 
-  function renouncePauser() public {
+    function renouncePauser() public {
-    _removePauser(msg.sender);
+        _removePauser(msg.sender);
-  }
+    }
 
-  function _addPauser(address account) internal {
+    function _addPauser(address account) internal {
-    pausers.add(account);
+        _pausers.add(account);
-    emit PauserAdded(account);
+        emit PauserAdded(account);
-  }
+    }
 
-  function _removePauser(address account) internal {
+    function _removePauser(address account) internal {
-    pausers.remove(account);
+        _pausers.remove(account);
-    emit PauserRemoved(account);
+        emit PauserRemoved(account);
-  }
+    }
 }

contracts/access/roles/SignerRole.sol

@@ -1,43 +1,43 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Roles.sol";
 
 contract SignerRole {
-  using Roles for Roles.Role;
+    using Roles for Roles.Role;
 
-  event SignerAdded(address indexed account);
+    event SignerAdded(address indexed account);
-  event SignerRemoved(address indexed account);
+    event SignerRemoved(address indexed account);
 
-  Roles.Role private signers;
+    Roles.Role private _signers;
 
-  constructor() internal {
+    constructor () internal {
-    _addSigner(msg.sender);
+        _addSigner(msg.sender);
-  }
+    }
 
-  modifier onlySigner() {
+    modifier onlySigner() {
-    require(isSigner(msg.sender));
+        require(isSigner(msg.sender));
-    _;
+        _;
-  }
+    }
 
-  function isSigner(address account) public view returns (bool) {
+    function isSigner(address account) public view returns (bool) {
-    return signers.has(account);
+        return _signers.has(account);
-  }
+    }
 
-  function addSigner(address account) public onlySigner {
+    function addSigner(address account) public onlySigner {
-    _addSigner(account);
+        _addSigner(account);
-  }
+    }
 
-  function renounceSigner() public {
+    function renounceSigner() public {
-    _removeSigner(msg.sender);
+        _removeSigner(msg.sender);
-  }
+    }
 
-  function _addSigner(address account) internal {
+    function _addSigner(address account) internal {
-    signers.add(account);
+        _signers.add(account);
-    emit SignerAdded(account);
+        emit SignerAdded(account);
-  }
+    }
 
-  function _removeSigner(address account) internal {
+    function _removeSigner(address account) internal {
-    signers.remove(account);
+        _signers.remove(account);
-    emit SignerRemoved(account);
+        emit SignerRemoved(account);
-  }
+    }
 }

contracts/access/roles/WhitelistAdminRole.sol

@@ -0,0 +1,47 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+
+/**
+ * @title WhitelistAdminRole
+ * @dev WhitelistAdmins are responsible for assigning and removing Whitelisted accounts.
+ */
+contract WhitelistAdminRole {
+    using Roles for Roles.Role;
+
+    event WhitelistAdminAdded(address indexed account);
+    event WhitelistAdminRemoved(address indexed account);
+
+    Roles.Role private _whitelistAdmins;
+
+    constructor () internal {
+        _addWhitelistAdmin(msg.sender);
+    }
+
+    modifier onlyWhitelistAdmin() {
+        require(isWhitelistAdmin(msg.sender));
+        _;
+    }
+
+    function isWhitelistAdmin(address account) public view returns (bool) {
+        return _whitelistAdmins.has(account);
+    }
+
+    function addWhitelistAdmin(address account) public onlyWhitelistAdmin {
+        _addWhitelistAdmin(account);
+    }
+
+    function renounceWhitelistAdmin() public {
+        _removeWhitelistAdmin(msg.sender);
+    }
+
+    function _addWhitelistAdmin(address account) internal {
+        _whitelistAdmins.add(account);
+        emit WhitelistAdminAdded(account);
+    }
+
+    function _removeWhitelistAdmin(address account) internal {
+        _whitelistAdmins.remove(account);
+        emit WhitelistAdminRemoved(account);
+    }
+}

contracts/access/roles/WhitelistedRole.sol

@@ -0,0 +1,50 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+import "./WhitelistAdminRole.sol";
+
+/**
+ * @title WhitelistedRole
+ * @dev Whitelisted accounts have been approved by a WhitelistAdmin to perform certain actions (e.g. participate in a
+ * crowdsale). This role is special in that the only accounts that can add it are WhitelistAdmins (who can also remove
+ * it), and not Whitelisteds themselves.
+ */
+contract WhitelistedRole is WhitelistAdminRole {
+    using Roles for Roles.Role;
+
+    event WhitelistedAdded(address indexed account);
+    event WhitelistedRemoved(address indexed account);
+
+    Roles.Role private _whitelisteds;
+
+    modifier onlyWhitelisted() {
+        require(isWhitelisted(msg.sender));
+        _;
+    }
+
+    function isWhitelisted(address account) public view returns (bool) {
+        return _whitelisteds.has(account);
+    }
+
+    function addWhitelisted(address account) public onlyWhitelistAdmin {
+        _addWhitelisted(account);
+    }
+
+    function removeWhitelisted(address account) public onlyWhitelistAdmin {
+        _removeWhitelisted(account);
+    }
+
+    function renounceWhitelisted() public {
+        _removeWhitelisted(msg.sender);
+    }
+
+    function _addWhitelisted(address account) internal {
+        _whitelisteds.add(account);
+        emit WhitelistedAdded(account);
+    }
+
+    function _removeWhitelisted(address account) internal {
+        _whitelisteds.remove(account);
+        emit WhitelistedRemoved(account);
+    }
+}

contracts/crowdsale/Crowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../math/SafeMath.sol";
@@ -18,224 +18,181 @@ import "../utils/ReentrancyGuard.sol";
  * behavior.
  */
 contract Crowdsale is ReentrancyGuard {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
-  using SafeERC20 for IERC20;
+    using SafeERC20 for IERC20;
 
-  // The token being sold
+    // The token being sold
-  IERC20 private _token;
+    IERC20 private _token;
 
-  // Address where funds are collected
+    // Address where funds are collected
-  address private _wallet;
+    address payable private _wallet;
 
-  // How many token units a buyer gets per wei.
+    // How many token units a buyer gets per wei.
-  // The rate is the conversion between wei and the smallest and indivisible token unit.
+    // The rate is the conversion between wei and the smallest and indivisible token unit.
-  // So, if you are using a rate of 1 with a ERC20Detailed token with 3 decimals called TOK
+    // So, if you are using a rate of 1 with a ERC20Detailed token with 3 decimals called TOK
-  // 1 wei will give you 1 unit, or 0.001 TOK.
+    // 1 wei will give you 1 unit, or 0.001 TOK.
-  uint256 private _rate;
+    uint256 private _rate;
 
-  // Amount of wei raised
+    // Amount of wei raised
-  uint256 private _weiRaised;
+    uint256 private _weiRaised;
 
-  /**
+    /**
-   * Event for token purchase logging
+     * Event for token purchase logging
-   * @param purchaser who paid for the tokens
+     * @param purchaser who paid for the tokens
-   * @param beneficiary who got the tokens
+     * @param beneficiary who got the tokens
-   * @param value weis paid for purchase
+     * @param value weis paid for purchase
-   * @param amount amount of tokens purchased
+     * @param amount amount of tokens purchased
-   */
+     */
-  event TokensPurchased(
+    event TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
-    address indexed purchaser,
-    address indexed beneficiary,
-    uint256 value,
-    uint256 amount
-  );
 
-  /**
+    /**
-   * @param rate Number of token units a buyer gets per wei
+     * @param rate Number of token units a buyer gets per wei
-   * @dev The rate is the conversion between wei and the smallest and indivisible
+     * @dev The rate is the conversion between wei and the smallest and indivisible
-   * token unit. So, if you are using a rate of 1 with a ERC20Detailed token
+     * token unit. So, if you are using a rate of 1 with a ERC20Detailed token
-   * with 3 decimals called TOK, 1 wei will give you 1 unit, or 0.001 TOK.
+     * with 3 decimals called TOK, 1 wei will give you 1 unit, or 0.001 TOK.
-   * @param wallet Address where collected funds will be forwarded to
+     * @param wallet Address where collected funds will be forwarded to
-   * @param token Address of the token being sold
+     * @param token Address of the token being sold
-   */
+     */
-  constructor(uint256 rate, address wallet, IERC20 token) internal {
+    constructor (uint256 rate, address payable wallet, IERC20 token) public {
-    require(rate > 0);
+        require(rate > 0);
-    require(wallet != address(0));
+        require(wallet != address(0));
-    require(token != address(0));
+        require(address(token) != address(0));
 
-    _rate = rate;
+        _rate = rate;
-    _wallet = wallet;
+        _wallet = wallet;
-    _token = token;
+        _token = token;
-  }
+    }
 
-  // -----------------------------------------
+    /**
-  // Crowdsale external interface
+     * @dev fallback function ***DO NOT OVERRIDE***
-  // -----------------------------------------
+     * Note that other contracts will transfer fund with a base gas stipend
+     * of 2300, which is not enough to call buyTokens. Consider calling
+     * buyTokens directly when purchasing tokens from a contract.
+     */
+    function () external payable {
+        buyTokens(msg.sender);
+    }
 
-  /**
+    /**
-   * @dev fallback function ***DO NOT OVERRIDE***
+     * @return the token being sold.
-   * Note that other contracts will transfer fund with a base gas stipend
+     */
-   * of 2300, which is not enough to call buyTokens. Consider calling
+    function token() public view returns (IERC20) {
-   * buyTokens directly when purchasing tokens from a contract.
+        return _token;
-   */
+    }
-  function () external payable {
-    buyTokens(msg.sender);
-  }
 
-  /**
+    /**
-   * @return the token being sold.
+     * @return the address where funds are collected.
-   */
+     */
-  function token() public view returns(IERC20) {
+    function wallet() public view returns (address payable) {
-    return _token;
+        return _wallet;
-  }
+    }
 
-  /**
+    /**
-   * @return the address where funds are collected.
+     * @return the number of token units a buyer gets per wei.
-   */
+     */
-  function wallet() public view returns(address) {
+    function rate() public view returns (uint256) {
-    return _wallet;
+        return _rate;
-  }
+    }
 
-  /**
+    /**
-   * @return the number of token units a buyer gets per wei.
+     * @return the amount of wei raised.
-   */
+     */
-  function rate() public view returns(uint256) {
+    function weiRaised() public view returns (uint256) {
-    return _rate;
+        return _weiRaised;
-  }
+    }
 
-  /**
+    /**
-   * @return the amount of wei raised.
+     * @dev low level token purchase ***DO NOT OVERRIDE***
-   */
+     * This function has a non-reentrancy guard, so it shouldn't be called by
-  function weiRaised() public view returns (uint256) {
+     * another `nonReentrant` function.
-    return _weiRaised;
+     * @param beneficiary Recipient of the token purchase
-  }
+     */
+    function buyTokens(address beneficiary) public nonReentrant payable {
+        uint256 weiAmount = msg.value;
+        _preValidatePurchase(beneficiary, weiAmount);
 
-  /**
+        // calculate token amount to be created
-   * @dev low level token purchase ***DO NOT OVERRIDE***
+        uint256 tokens = _getTokenAmount(weiAmount);
-   * This function has a non-reentrancy guard, so it shouldn't be called by
-   * another `nonReentrant` function.
-   * @param beneficiary Recipient of the token purchase
-   */
-  function buyTokens(address beneficiary) public nonReentrant payable {
 
-    uint256 weiAmount = msg.value;
+        // update state
-    _preValidatePurchase(beneficiary, weiAmount);
+        _weiRaised = _weiRaised.add(weiAmount);
 
-    // calculate token amount to be created
+        _processPurchase(beneficiary, tokens);
-    uint256 tokens = _getTokenAmount(weiAmount);
+        emit TokensPurchased(msg.sender, beneficiary, weiAmount, tokens);
 
-    // update state
+        _updatePurchasingState(beneficiary, weiAmount);
-    _weiRaised = _weiRaised.add(weiAmount);
 
-    _processPurchase(beneficiary, tokens);
+        _forwardFunds();
-    emit TokensPurchased(
+        _postValidatePurchase(beneficiary, weiAmount);
-      msg.sender,
+    }
-      beneficiary,
-      weiAmount,
-      tokens
-    );
 
-    _updatePurchasingState(beneficiary, weiAmount);
+    /**
+     * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met.
+     * Use `super` in contracts that inherit from Crowdsale to extend their validations.
+     * Example from CappedCrowdsale.sol's _preValidatePurchase method:
+     *     super._preValidatePurchase(beneficiary, weiAmount);
+     *     require(weiRaised().add(weiAmount) <= cap);
+     * @param beneficiary Address performing the token purchase
+     * @param weiAmount Value in wei involved in the purchase
+     */
+    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
+        require(beneficiary != address(0));
+        require(weiAmount != 0);
+    }
 
-    _forwardFunds();
+    /**
-    _postValidatePurchase(beneficiary, weiAmount);
+     * @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid
-  }
+     * conditions are not met.
+     * @param beneficiary Address performing the token purchase
+     * @param weiAmount Value in wei involved in the purchase
+     */
+    function _postValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  // -----------------------------------------
+    /**
-  // Internal interface (extensible)
+     * @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends
-  // -----------------------------------------
+     * its tokens.
+     * @param beneficiary Address performing the token purchase
+     * @param tokenAmount Number of tokens to be emitted
+     */
+    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
+        _token.safeTransfer(beneficiary, tokenAmount);
+    }
 
-  /**
+    /**
-   * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met. Use `super` in contracts that inherit from Crowdsale to extend their validations.
+     * @dev Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send
-   * Example from CappedCrowdsale.sol's _preValidatePurchase method:
+     * tokens.
-   *   super._preValidatePurchase(beneficiary, weiAmount);
+     * @param beneficiary Address receiving the tokens
-   *   require(weiRaised().add(weiAmount) <= cap);
+     * @param tokenAmount Number of tokens to be purchased
-   * @param beneficiary Address performing the token purchase
+     */
-   * @param weiAmount Value in wei involved in the purchase
+    function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
-   */
+        _deliverTokens(beneficiary, tokenAmount);
-  function _preValidatePurchase(
+    }
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-    view
-  {
-    require(beneficiary != address(0));
-    require(weiAmount != 0);
-  }
 
-  /**
+    /**
-   * @dev Validation of an executed purchase. Observe state and use revert statements to undo rollback when valid conditions are not met.
+     * @dev Override for extensions that require an internal state to check for validity (current user contributions,
-   * @param beneficiary Address performing the token purchase
+     * etc.)
-   * @param weiAmount Value in wei involved in the purchase
+     * @param beneficiary Address receiving the tokens
-   */
+     * @param weiAmount Value in wei involved in the purchase
-  function _postValidatePurchase(
+     */
-    address beneficiary,
+    function _updatePurchasingState(address beneficiary, uint256 weiAmount) internal {
-    uint256 weiAmount
+        // solhint-disable-previous-line no-empty-blocks
-  )
+    }
-    internal
-    view
-  {
-    // optional override
-  }
 
-  /**
+    /**
-   * @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends its tokens.
+     * @dev Override to extend the way in which ether is converted to tokens.
-   * @param beneficiary Address performing the token purchase
+     * @param weiAmount Value in wei to be converted into tokens
-   * @param tokenAmount Number of tokens to be emitted
+     * @return Number of tokens that can be purchased with the specified _weiAmount
-   */
+     */
-  function _deliverTokens(
+    function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
-    address beneficiary,
+        return weiAmount.mul(_rate);
-    uint256 tokenAmount
+    }
-  )
-    internal
-  {
-    _token.safeTransfer(beneficiary, tokenAmount);
-  }
 
-  /**
+    /**
-   * @dev Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send tokens.
+     * @dev Determines how ETH is stored/forwarded on purchases.
-   * @param beneficiary Address receiving the tokens
+     */
-   * @param tokenAmount Number of tokens to be purchased
+    function _forwardFunds() internal {
-   */
+        _wallet.transfer(msg.value);
-  function _processPurchase(
+    }
-    address beneficiary,
-    uint256 tokenAmount
-  )
-    internal
-  {
-    _deliverTokens(beneficiary, tokenAmount);
-  }
-
-  /**
-   * @dev Override for extensions that require an internal state to check for validity (current user contributions, etc.)
-   * @param beneficiary Address receiving the tokens
-   * @param weiAmount Value in wei involved in the purchase
-   */
-  function _updatePurchasingState(
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-  {
-    // optional override
-  }
-
-  /**
-   * @dev Override to extend the way in which ether is converted to tokens.
-   * @param weiAmount Value in wei to be converted into tokens
-   * @return Number of tokens that can be purchased with the specified _weiAmount
-   */
-  function _getTokenAmount(uint256 weiAmount)
-    internal view returns (uint256)
-  {
-    return weiAmount.mul(_rate);
-  }
-
-  /**
-   * @dev Determines how ETH is stored/forwarded on purchases.
-   */
-  function _forwardFunds() internal {
-    _wallet.transfer(msg.value);
-  }
 }

contracts/crowdsale/distribution/FinalizableCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../validation/TimedCrowdsale.sol";
@@ -9,42 +9,43 @@ import "../validation/TimedCrowdsale.sol";
  * can do extra work after finishing.
  */
 contract FinalizableCrowdsale is TimedCrowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  bool private _finalized;
+    bool private _finalized;
 
-  event CrowdsaleFinalized();
+    event CrowdsaleFinalized();
 
-  constructor() internal {
+    constructor () internal {
-    _finalized = false;
+        _finalized = false;
-  }
+    }
 
-  /**
+    /**
-   * @return true if the crowdsale is finalized, false otherwise.
+     * @return true if the crowdsale is finalized, false otherwise.
-   */
+     */
-  function finalized() public view returns (bool) {
+    function finalized() public view returns (bool) {
-    return _finalized;
+        return _finalized;
-  }
+    }
 
-  /**
+    /**
-   * @dev Must be called after crowdsale ends, to do some extra finalization
+     * @dev Must be called after crowdsale ends, to do some extra finalization
-   * work. Calls the contract's finalization function.
+     * work. Calls the contract's finalization function.
-   */
+     */
-  function finalize() public {
+    function finalize() public {
-    require(!_finalized);
+        require(!_finalized);
-    require(hasClosed());
+        require(hasClosed());
 
-    _finalized = true;
+        _finalized = true;
 
-    _finalization();
+        _finalization();
-    emit CrowdsaleFinalized();
+        emit CrowdsaleFinalized();
-  }
+    }
 
-  /**
+    /**
-   * @dev Can be overridden to add finalization logic. The overriding function
+     * @dev Can be overridden to add finalization logic. The overriding function
-   * should call super._finalization() to ensure the chain of finalization is
+     * should call super._finalization() to ensure the chain of finalization is
-   * executed entirely.
+     * executed entirely.
-   */
+     */
-  function _finalization() internal {
+    function _finalization() internal {
-  }
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/crowdsale/distribution/PostDeliveryCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../validation/TimedCrowdsale.sol";
 import "../../math/SafeMath.sol";
@@ -8,43 +8,36 @@ import "../../math/SafeMath.sol";
  * @dev Crowdsale that locks tokens from withdrawal until it ends.
  */
 contract PostDeliveryCrowdsale is TimedCrowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  mapping(address => uint256) private _balances;
+    mapping(address => uint256) private _balances;
 
-  constructor() internal {}
+    /**
+     * @dev Withdraw tokens only after crowdsale ends.
+     * @param beneficiary Whose tokens will be withdrawn.
+     */
+    function withdrawTokens(address beneficiary) public {
+        require(hasClosed());
+        uint256 amount = _balances[beneficiary];
+        require(amount > 0);
+        _balances[beneficiary] = 0;
+        _deliverTokens(beneficiary, amount);
+    }
 
-  /**
+    /**
-   * @dev Withdraw tokens only after crowdsale ends.
+     * @return the balance of an account.
-   * @param beneficiary Whose tokens will be withdrawn.
+     */
-   */
+    function balanceOf(address account) public view returns (uint256) {
-  function withdrawTokens(address beneficiary) public {
+        return _balances[account];
-    require(hasClosed());
+    }
-    uint256 amount = _balances[beneficiary];
-    require(amount > 0);
-    _balances[beneficiary] = 0;
-    _deliverTokens(beneficiary, amount);
-  }
 
-  /**
+    /**
-   * @return the balance of an account.
+     * @dev Overrides parent by storing balances instead of issuing tokens right away.
-   */
+     * @param beneficiary Token purchaser
-  function balanceOf(address account) public view returns(uint256) {
+     * @param tokenAmount Amount of tokens purchased
-    return _balances[account];
+     */
-  }
+    function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
-
+        _balances[beneficiary] = _balances[beneficiary].add(tokenAmount);
-  /**
+    }
-   * @dev Overrides parent by storing balances instead of issuing tokens right away.
-   * @param beneficiary Token purchaser
-   * @param tokenAmount Amount of tokens purchased
-   */
-  function _processPurchase(
-    address beneficiary,
-    uint256 tokenAmount
-  )
-    internal
-  {
-    _balances[beneficiary] = _balances[beneficiary].add(tokenAmount);
-  }
 
 }

contracts/crowdsale/distribution/RefundableCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "./FinalizableCrowdsale.sol";
@@ -6,86 +6,77 @@ import "../../payment/escrow/RefundEscrow.sol";
 
 /**
  * @title RefundableCrowdsale
- * @dev Extension of Crowdsale contract that adds a funding goal, and
+ * @dev Extension of Crowdsale contract that adds a funding goal, and the possibility of users getting a refund if goal
- * the possibility of users getting a refund if goal is not met.
+ * is not met.
- * WARNING: note that if you allow tokens to be traded before the goal 
+ *
- * is met, then an attack is possible in which the attacker purchases 
+ * Deprecated, use RefundablePostDeliveryCrowdsale instead. Note that if you allow tokens to be traded before the goal
- * tokens from the crowdsale and when they sees that the goal is 
+ * is met, then an attack is possible in which the attacker purchases tokens from the crowdsale and when they sees that
- * unlikely to be met, they sell their tokens (possibly at a discount).
+ * the goal is unlikely to be met, they sell their tokens (possibly at a discount). The attacker will be refunded when
- * The attacker will be refunded when the crowdsale is finalized, and
+ * the crowdsale is finalized, and the users that purchased from them will be left with worthless tokens.
- * the users that purchased from them will be left with worthless 
- * tokens. There are many possible ways to avoid this, like making the
- * the crowdsale inherit from PostDeliveryCrowdsale, or imposing 
- * restrictions on token trading until the crowdsale is finalized.
- * This is being discussed in 
- * https://github.com/OpenZeppelin/openzeppelin-solidity/issues/877
- * This contract will be updated when we agree on a general solution
- * for this problem.
  */
 contract RefundableCrowdsale is FinalizableCrowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  // minimum amount of funds to be raised in weis
+    // minimum amount of funds to be raised in weis
-  uint256 private _goal;
+    uint256 private _goal;
 
-  // refund escrow used to hold funds while crowdsale is running
+    // refund escrow used to hold funds while crowdsale is running
-  RefundEscrow private _escrow;
+    RefundEscrow private _escrow;
 
-  /**
+    /**
-   * @dev Constructor, creates RefundEscrow.
+     * @dev Constructor, creates RefundEscrow.
-   * @param goal Funding goal
+     * @param goal Funding goal
-   */
+     */
-  constructor(uint256 goal) internal {
+    constructor (uint256 goal) public {
-    require(goal > 0);
+        require(goal > 0);
-    _escrow = new RefundEscrow(wallet());
+        _escrow = new RefundEscrow(wallet());
-    _goal = goal;
+        _goal = goal;
-  }
-
-  /**
-   * @return minimum amount of funds to be raised in wei.
-   */
-  function goal() public view returns(uint256) {
-    return _goal;
-  }
-
-  /**
-   * @dev Investors can claim refunds here if crowdsale is unsuccessful
-   * @param beneficiary Whose refund will be claimed.
-   */
-  function claimRefund(address beneficiary) public {
-    require(finalized());
-    require(!goalReached());
-
-    _escrow.withdraw(beneficiary);
-  }
-
-  /**
-   * @dev Checks whether funding goal was reached.
-   * @return Whether funding goal was reached
-   */
-  function goalReached() public view returns (bool) {
-    return weiRaised() >= _goal;
-  }
-
-  /**
-   * @dev escrow finalization task, called when finalize() is called
-   */
-  function _finalization() internal {
-    if (goalReached()) {
-      _escrow.close();
-      _escrow.beneficiaryWithdraw();
-    } else {
-      _escrow.enableRefunds();
     }
 
-    super._finalization();
+    /**
-  }
+     * @return minimum amount of funds to be raised in wei.
+     */
+    function goal() public view returns (uint256) {
+        return _goal;
+    }
 
-  /**
+    /**
-   * @dev Overrides Crowdsale fund forwarding, sending funds to escrow.
+     * @dev Investors can claim refunds here if crowdsale is unsuccessful
-   */
+     * @param refundee Whose refund will be claimed.
-  function _forwardFunds() internal {
+     */
-    _escrow.deposit.value(msg.value)(msg.sender);
+    function claimRefund(address payable refundee) public {
-  }
+        require(finalized());
+        require(!goalReached());
 
+        _escrow.withdraw(refundee);
+    }
+
+    /**
+     * @dev Checks whether funding goal was reached.
+     * @return Whether funding goal was reached
+     */
+    function goalReached() public view returns (bool) {
+        return weiRaised() >= _goal;
+    }
+
+    /**
+     * @dev escrow finalization task, called when finalize() is called
+     */
+    function _finalization() internal {
+        if (goalReached()) {
+            _escrow.close();
+            _escrow.beneficiaryWithdraw();
+        } else {
+            _escrow.enableRefunds();
+        }
+
+        super._finalization();
+    }
+
+    /**
+     * @dev Overrides Crowdsale fund forwarding, sending funds to escrow.
+     */
+    function _forwardFunds() internal {
+        _escrow.deposit.value(msg.value)(msg.sender);
+    }
 }

contracts/crowdsale/distribution/RefundablePostDeliveryCrowdsale.sol

@@ -0,0 +1,20 @@
+pragma solidity ^0.5.0;
+
+import "./RefundableCrowdsale.sol";
+import "./PostDeliveryCrowdsale.sol";
+
+
+/**
+ * @title RefundablePostDeliveryCrowdsale
+ * @dev Extension of RefundableCrowdsale contract that only delivers the tokens
+ * once the crowdsale has closed and the goal met, preventing refunds to be issued
+ * to token holders.
+ */
+contract RefundablePostDeliveryCrowdsale is RefundableCrowdsale, PostDeliveryCrowdsale {
+    function withdrawTokens(address beneficiary) public {
+        require(finalized());
+        require(goalReached());
+
+        super.withdrawTokens(beneficiary);
+    }
+}

contracts/crowdsale/emission/AllowanceCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Crowdsale.sol";
 import "../../token/ERC20/IERC20.sol";
@@ -11,49 +11,41 @@ import "../../math/Math.sol";
  * @dev Extension of Crowdsale where tokens are held by a wallet, which approves an allowance to the crowdsale.
  */
 contract AllowanceCrowdsale is Crowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
-  using SafeERC20 for IERC20;
+    using SafeERC20 for IERC20;
 
-  address private _tokenWallet;
+    address private _tokenWallet;
 
-  /**
+    /**
-   * @dev Constructor, takes token wallet address.
+     * @dev Constructor, takes token wallet address.
-   * @param tokenWallet Address holding the tokens, which has approved allowance to the crowdsale
+     * @param tokenWallet Address holding the tokens, which has approved allowance to the crowdsale
-   */
+     */
-  constructor(address tokenWallet) internal {
+    constructor (address tokenWallet) public {
-    require(tokenWallet != address(0));
+        require(tokenWallet != address(0));
-    _tokenWallet = tokenWallet;
+        _tokenWallet = tokenWallet;
-  }
+    }
 
-  /**
+    /**
-   * @return the address of the wallet that will hold the tokens.
+     * @return the address of the wallet that will hold the tokens.
-   */
+     */
-  function tokenWallet() public view returns(address) {
+    function tokenWallet() public view returns (address) {
-    return _tokenWallet;
+        return _tokenWallet;
-  }
+    }
 
-  /**
+    /**
-   * @dev Checks the amount of tokens left in the allowance.
+     * @dev Checks the amount of tokens left in the allowance.
-   * @return Amount of tokens left in the allowance
+     * @return Amount of tokens left in the allowance
-   */
+     */
-  function remainingTokens() public view returns (uint256) {
+    function remainingTokens() public view returns (uint256) {
-    return Math.min(
+        return Math.min(token().balanceOf(_tokenWallet), token().allowance(_tokenWallet, address(this)));
-      token().balanceOf(_tokenWallet),
+    }
-      token().allowance(_tokenWallet, this)
-    );
-  }
 
-  /**
+    /**
-   * @dev Overrides parent behavior by transferring tokens from wallet.
+     * @dev Overrides parent behavior by transferring tokens from wallet.
-   * @param beneficiary Token purchaser
+     * @param beneficiary Token purchaser
-   * @param tokenAmount Amount of tokens purchased
+     * @param tokenAmount Amount of tokens purchased
-   */
+     */
-  function _deliverTokens(
+    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
-    address beneficiary,
+        token().safeTransferFrom(_tokenWallet, beneficiary, tokenAmount);
-    uint256 tokenAmount
+    }
-  )
-    internal
-  {
-    token().safeTransferFrom(_tokenWallet, beneficiary, tokenAmount);
-  }
 }

contracts/crowdsale/emission/MintedCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Crowdsale.sol";
 import "../../token/ERC20/ERC20Mintable.sol";
@@ -9,21 +9,13 @@ import "../../token/ERC20/ERC20Mintable.sol";
  * Token ownership should be transferred to MintedCrowdsale for minting.
  */
 contract MintedCrowdsale is Crowdsale {
-  constructor() internal {}
+    /**
-
+     * @dev Overrides delivery by minting tokens upon purchase.
-  /**
+     * @param beneficiary Token purchaser
-   * @dev Overrides delivery by minting tokens upon purchase.
+     * @param tokenAmount Number of tokens to be minted
-   * @param beneficiary Token purchaser
+     */
-   * @param tokenAmount Number of tokens to be minted
+    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
-   */
+        // Potentially dangerous assumption about the type of the token.
-  function _deliverTokens(
+        require(ERC20Mintable(address(token())).mint(beneficiary, tokenAmount));
-    address beneficiary,
+    }
-    uint256 tokenAmount
-  )
-    internal
-  {
-    // Potentially dangerous assumption about the type of the token.
-    require(
-      ERC20Mintable(address(token())).mint(beneficiary, tokenAmount));
-  }
 }

contracts/crowdsale/price/IncreasingPriceCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../validation/TimedCrowdsale.sol";
 import "../../math/SafeMath.sol";
@@ -10,72 +10,69 @@ import "../../math/SafeMath.sol";
  * the amount of tokens per wei contributed. Thus, the initial rate must be greater than the final rate.
  */
 contract IncreasingPriceCrowdsale is TimedCrowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  uint256 private _initialRate;
+    uint256 private _initialRate;
-  uint256 private _finalRate;
+    uint256 private _finalRate;
 
-  /**
+    /**
-   * @dev Constructor, takes initial and final rates of tokens received per wei contributed.
+     * @dev Constructor, takes initial and final rates of tokens received per wei contributed.
-   * @param initialRate Number of tokens a buyer gets per wei at the start of the crowdsale
+     * @param initialRate Number of tokens a buyer gets per wei at the start of the crowdsale
-   * @param finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
+     * @param finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
-   */
+     */
-  constructor(uint256 initialRate, uint256 finalRate) internal {
+    constructor (uint256 initialRate, uint256 finalRate) public {
-    require(finalRate > 0);
+        require(finalRate > 0);
-    require(initialRate > finalRate);
+        require(initialRate > finalRate);
-    _initialRate = initialRate;
+        _initialRate = initialRate;
-    _finalRate = finalRate;
+        _finalRate = finalRate;
-  }
-
-  /**
-   * The base rate function is overridden to revert, since this crowdsale doens't use it, and
-   * all calls to it are a mistake.
-   */
-  function rate() public view returns(uint256) {
-    revert();
-  }
-
-  /**
-   * @return the initial rate of the crowdsale.
-   */
-  function initialRate() public view returns(uint256) {
-    return _initialRate;
-  }
-
-  /**
-   * @return the final rate of the crowdsale.
-   */
-  function finalRate() public view returns (uint256) {
-    return _finalRate;
-  }
-
-  /**
-   * @dev Returns the rate of tokens per wei at the present time.
-   * Note that, as price _increases_ with time, the rate _decreases_.
-   * @return The number of tokens a buyer gets per wei at a given time
-   */
-  function getCurrentRate() public view returns (uint256) {
-    if (!isOpen()) {
-      return 0;
     }
 
-    // solium-disable-next-line security/no-block-members
+    /**
-    uint256 elapsedTime = block.timestamp.sub(openingTime());
+     * The base rate function is overridden to revert, since this crowdsale doens't use it, and
-    uint256 timeRange = closingTime().sub(openingTime());
+     * all calls to it are a mistake.
-    uint256 rateRange = _initialRate.sub(_finalRate);
+     */
-    return _initialRate.sub(elapsedTime.mul(rateRange).div(timeRange));
+    function rate() public view returns (uint256) {
-  }
+        revert();
+    }
 
-  /**
+    /**
-   * @dev Overrides parent method taking into account variable rate.
+     * @return the initial rate of the crowdsale.
-   * @param weiAmount The value in wei to be converted into tokens
+     */
-   * @return The number of tokens _weiAmount wei will buy at present time
+    function initialRate() public view returns (uint256) {
-   */
+        return _initialRate;
-  function _getTokenAmount(uint256 weiAmount)
+    }
-    internal view returns (uint256)
-  {
-    uint256 currentRate = getCurrentRate();
-    return currentRate.mul(weiAmount);
-  }
 
+    /**
+     * @return the final rate of the crowdsale.
+     */
+    function finalRate() public view returns (uint256) {
+        return _finalRate;
+    }
+
+    /**
+     * @dev Returns the rate of tokens per wei at the present time.
+     * Note that, as price _increases_ with time, the rate _decreases_.
+     * @return The number of tokens a buyer gets per wei at a given time
+     */
+    function getCurrentRate() public view returns (uint256) {
+        if (!isOpen()) {
+            return 0;
+        }
+
+        // solhint-disable-next-line not-rely-on-time
+        uint256 elapsedTime = block.timestamp.sub(openingTime());
+        uint256 timeRange = closingTime().sub(openingTime());
+        uint256 rateRange = _initialRate.sub(_finalRate);
+        return _initialRate.sub(elapsedTime.mul(rateRange).div(timeRange));
+    }
+
+    /**
+     * @dev Overrides parent method taking into account variable rate.
+     * @param weiAmount The value in wei to be converted into tokens
+     * @return The number of tokens _weiAmount wei will buy at present time
+     */
+    function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
+        uint256 currentRate = getCurrentRate();
+        return currentRate.mul(weiAmount);
+    }
 }

contracts/crowdsale/validation/CappedCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
@@ -8,48 +8,41 @@ import "../Crowdsale.sol";
  * @dev Crowdsale with a limit for total contributions.
  */
 contract CappedCrowdsale is Crowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  uint256 private _cap;
+    uint256 private _cap;
 
-  /**
+    /**
-   * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
+     * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
-   * @param cap Max amount of wei to be contributed
+     * @param cap Max amount of wei to be contributed
-   */
+     */
-  constructor(uint256 cap) internal {
+    constructor (uint256 cap) public {
-    require(cap > 0);
+        require(cap > 0);
-    _cap = cap;
+        _cap = cap;
-  }
+    }
 
-  /**
+    /**
-   * @return the cap of the crowdsale.
+     * @return the cap of the crowdsale.
-   */
+     */
-  function cap() public view returns(uint256) {
+    function cap() public view returns (uint256) {
-    return _cap;
+        return _cap;
-  }
+    }
 
-  /**
+    /**
-   * @dev Checks whether the cap has been reached.
+     * @dev Checks whether the cap has been reached.
-   * @return Whether the cap was reached
+     * @return Whether the cap was reached
-   */
+     */
-  function capReached() public view returns (bool) {
+    function capReached() public view returns (bool) {
-    return weiRaised() >= _cap;
+        return weiRaised() >= _cap;
-  }
+    }
-
-  /**
-   * @dev Extend parent behavior requiring purchase to respect the funding cap.
-   * @param beneficiary Token purchaser
-   * @param weiAmount Amount of wei contributed
-   */
-  function _preValidatePurchase(
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-    view
-  {
-    super._preValidatePurchase(beneficiary, weiAmount);
-    require(weiRaised().add(weiAmount) <= _cap);
-  }
 
+    /**
+     * @dev Extend parent behavior requiring purchase to respect the funding cap.
+     * @param beneficiary Token purchaser
+     * @param weiAmount Amount of wei contributed
+     */
+    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
+        super._preValidatePurchase(beneficiary, weiAmount);
+        require(weiRaised().add(weiAmount) <= _cap);
+    }
 }

contracts/crowdsale/validation/IndividuallyCappedCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
@@ -9,73 +9,55 @@ import "../../access/roles/CapperRole.sol";
  * @dev Crowdsale with per-beneficiary caps.
  */
 contract IndividuallyCappedCrowdsale is Crowdsale, CapperRole {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  mapping(address => uint256) private _contributions;
+    mapping(address => uint256) private _contributions;
-  mapping(address => uint256) private _caps;
+    mapping(address => uint256) private _caps;
 
-  constructor() internal {}
+    /**
+     * @dev Sets a specific beneficiary's maximum contribution.
+     * @param beneficiary Address to be capped
+     * @param cap Wei limit for individual contribution
+     */
+    function setCap(address beneficiary, uint256 cap) external onlyCapper {
+        _caps[beneficiary] = cap;
+    }
 
-  /**
+    /**
-   * @dev Sets a specific beneficiary's maximum contribution.
+     * @dev Returns the cap of a specific beneficiary.
-   * @param beneficiary Address to be capped
+     * @param beneficiary Address whose cap is to be checked
-   * @param cap Wei limit for individual contribution
+     * @return Current cap for individual beneficiary
-   */
+     */
-  function setCap(address beneficiary, uint256 cap) external onlyCapper {
+    function getCap(address beneficiary) public view returns (uint256) {
-    _caps[beneficiary] = cap;
+        return _caps[beneficiary];
-  }
+    }
 
-  /**
+    /**
-   * @dev Returns the cap of a specific beneficiary.
+     * @dev Returns the amount contributed so far by a specific beneficiary.
-   * @param beneficiary Address whose cap is to be checked
+     * @param beneficiary Address of contributor
-   * @return Current cap for individual beneficiary
+     * @return Beneficiary contribution so far
-   */
+     */
-  function getCap(address beneficiary) public view returns (uint256) {
+    function getContribution(address beneficiary) public view returns (uint256) {
-    return _caps[beneficiary];
+        return _contributions[beneficiary];
-  }
+    }
 
-  /**
+    /**
-   * @dev Returns the amount contributed so far by a specific beneficiary.
+     * @dev Extend parent behavior requiring purchase to respect the beneficiary's funding cap.
-   * @param beneficiary Address of contributor
+     * @param beneficiary Token purchaser
-   * @return Beneficiary contribution so far
+     * @param weiAmount Amount of wei contributed
-   */
+     */
-  function getContribution(address beneficiary)
+    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
-    public view returns (uint256)
+        super._preValidatePurchase(beneficiary, weiAmount);
-  {
+        require(_contributions[beneficiary].add(weiAmount) <= _caps[beneficiary]);
-    return _contributions[beneficiary];
+    }
-  }
-
-  /**
-   * @dev Extend parent behavior requiring purchase to respect the beneficiary's funding cap.
-   * @param beneficiary Token purchaser
-   * @param weiAmount Amount of wei contributed
-   */
-  function _preValidatePurchase(
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-    view
-  {
-    super._preValidatePurchase(beneficiary, weiAmount);
-    require(
-      _contributions[beneficiary].add(weiAmount) <= _caps[beneficiary]);
-  }
-
-  /**
-   * @dev Extend parent behavior to update beneficiary contributions
-   * @param beneficiary Token purchaser
-   * @param weiAmount Amount of wei contributed
-   */
-  function _updatePurchasingState(
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-  {
-    super._updatePurchasingState(beneficiary, weiAmount);
-    _contributions[beneficiary] = _contributions[beneficiary].add(
-      weiAmount);
-  }
 
+    /**
+     * @dev Extend parent behavior to update beneficiary contributions
+     * @param beneficiary Token purchaser
+     * @param weiAmount Amount of wei contributed
+     */
+    function _updatePurchasingState(address beneficiary, uint256 weiAmount) internal {
+        super._updatePurchasingState(beneficiary, weiAmount);
+        _contributions[beneficiary] = _contributions[beneficiary].add(weiAmount);
+    }
 }

contracts/crowdsale/validation/PausableCrowdsale.sol

@@ -0,0 +1,21 @@
+pragma solidity ^0.5.0;
+
+import "../Crowdsale.sol";
+import "../../lifecycle/Pausable.sol";
+
+/**
+ * @title PausableCrowdsale
+ * @dev Extension of Crowdsale contract where purchases can be paused and unpaused by the pauser role.
+ */
+contract PausableCrowdsale is Crowdsale, Pausable {
+    /**
+     * @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met.
+     * Use super to concatenate validations.
+     * Adds the validation that the crowdsale must not be paused.
+     * @param _beneficiary Address performing the token purchase
+     * @param _weiAmount Value in wei involved in the purchase
+     */
+    function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal view whenNotPaused {
+        return super._preValidatePurchase(_beneficiary, _weiAmount);
+    }
+}

contracts/crowdsale/validation/TimedCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
@@ -8,78 +8,70 @@ import "../Crowdsale.sol";
  * @dev Crowdsale accepting contributions only within a time frame.
  */
 contract TimedCrowdsale is Crowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  uint256 private _openingTime;
+    uint256 private _openingTime;
-  uint256 private _closingTime;
+    uint256 private _closingTime;
 
-  /**
+    /**
-   * @dev Reverts if not in crowdsale time range.
+     * @dev Reverts if not in crowdsale time range.
-   */
+     */
-  modifier onlyWhileOpen {
+    modifier onlyWhileOpen {
-    require(isOpen());
+        require(isOpen());
-    _;
+        _;
-  }
+    }
 
-  /**
+    /**
-   * @dev Constructor, takes crowdsale opening and closing times.
+     * @dev Constructor, takes crowdsale opening and closing times.
-   * @param openingTime Crowdsale opening time
+     * @param openingTime Crowdsale opening time
-   * @param closingTime Crowdsale closing time
+     * @param closingTime Crowdsale closing time
-   */
+     */
-  constructor(uint256 openingTime, uint256 closingTime) internal {
+    constructor (uint256 openingTime, uint256 closingTime) public {
-    // solium-disable-next-line security/no-block-members
+        // solhint-disable-next-line not-rely-on-time
-    require(openingTime >= block.timestamp);
+        require(openingTime >= block.timestamp);
-    require(closingTime > openingTime);
+        require(closingTime > openingTime);
 
-    _openingTime = openingTime;
+        _openingTime = openingTime;
-    _closingTime = closingTime;
+        _closingTime = closingTime;
-  }
+    }
 
-  /**
+    /**
-   * @return the crowdsale opening time.
+     * @return the crowdsale opening time.
-   */
+     */
-  function openingTime() public view returns(uint256) {
+    function openingTime() public view returns (uint256) {
-    return _openingTime;
+        return _openingTime;
-  }
+    }
 
-  /**
+    /**
-   * @return the crowdsale closing time.
+     * @return the crowdsale closing time.
-   */
+     */
-  function closingTime() public view returns(uint256) {
+    function closingTime() public view returns (uint256) {
-    return _closingTime;
+        return _closingTime;
-  }
+    }
 
-  /**
+    /**
-   * @return true if the crowdsale is open, false otherwise.
+     * @return true if the crowdsale is open, false otherwise.
-   */
+     */
-  function isOpen() public view returns (bool) {
+    function isOpen() public view returns (bool) {
-    // solium-disable-next-line security/no-block-members
+        // solhint-disable-next-line not-rely-on-time
-    return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
+        return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
-  }
+    }
 
-  /**
+    /**
-   * @dev Checks whether the period in which the crowdsale is open has already elapsed.
+     * @dev Checks whether the period in which the crowdsale is open has already elapsed.
-   * @return Whether crowdsale period has elapsed
+     * @return Whether crowdsale period has elapsed
-   */
+     */
-  function hasClosed() public view returns (bool) {
+    function hasClosed() public view returns (bool) {
-    // solium-disable-next-line security/no-block-members
+        // solhint-disable-next-line not-rely-on-time
-    return block.timestamp > _closingTime;
+        return block.timestamp > _closingTime;
-  }
+    }
-
-  /**
-   * @dev Extend parent behavior requiring to be within contributing period
-   * @param beneficiary Token purchaser
-   * @param weiAmount Amount of wei contributed
-   */
-  function _preValidatePurchase(
-    address beneficiary,
-    uint256 weiAmount
-  )
-    internal
-    onlyWhileOpen
-    view
-  {
-    super._preValidatePurchase(beneficiary, weiAmount);
-  }
 
+    /**
+     * @dev Extend parent behavior requiring to be within contributing period
+     * @param beneficiary Token purchaser
+     * @param weiAmount Amount of wei contributed
+     */
+    function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal onlyWhileOpen view {
+        super._preValidatePurchase(beneficiary, weiAmount);
+    }
 }

contracts/crowdsale/validation/WhitelistCrowdsale.sol

@@ -0,0 +1,21 @@
+pragma solidity ^0.5.0;
+import "../Crowdsale.sol";
+import "../../access/roles/WhitelistedRole.sol";
+
+
+/**
+ * @title WhitelistCrowdsale
+ * @dev Crowdsale in which only whitelisted users can contribute.
+ */
+contract WhitelistCrowdsale is WhitelistedRole, Crowdsale {
+    /**
+    * @dev Extend parent behavior requiring beneficiary to be whitelisted. Note that no
+    * restriction is imposed on the account sending the transaction.
+    * @param _beneficiary Token beneficiary
+    * @param _weiAmount Amount of wei contributed
+    */
+    function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal view {
+        require(isWhitelisted(_beneficiary));
+        super._preValidatePurchase(_beneficiary, _weiAmount);
+    }
+}

contracts/cryptography/ECDSA.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title Elliptic curve signature operations
@@ -8,64 +8,52 @@ pragma solidity ^0.4.24;
  */
 
 library ECDSA {
+    /**
+     * @dev Recover signer address from a message by using their signature
+     * @param hash bytes32 message, the hash is the signed message. What is recovered is the signer address.
+     * @param signature bytes signature, the signature is generated using web3.eth.sign()
+     */
+    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
+        bytes32 r;
+        bytes32 s;
+        uint8 v;
 
-  /**
+        // Check the signature length
-   * @dev Recover signer address from a message by using their signature
+        if (signature.length != 65) {
-   * @param hash bytes32 message, the hash is the signed message. What is recovered is the signer address.
+            return (address(0));
-   * @param signature bytes signature, the signature is generated using web3.eth.sign()
+        }
-   */
-  function recover(bytes32 hash, bytes signature)
-    internal
-    pure
-    returns (address)
-  {
-    bytes32 r;
-    bytes32 s;
-    uint8 v;
 
-    // Check the signature length
+        // Divide the signature in r, s and v variables
-    if (signature.length != 65) {
+        // ecrecover takes the signature parameters, and the only way to get them
-      return (address(0));
+        // currently is to use assembly.
+        // solhint-disable-next-line no-inline-assembly
+        assembly {
+            r := mload(add(signature, 0x20))
+            s := mload(add(signature, 0x40))
+            v := byte(0, mload(add(signature, 0x60)))
+        }
+
+        // Version of signature should be 27 or 28, but 0 and 1 are also possible versions
+        if (v < 27) {
+            v += 27;
+        }
+
+        // If the version is correct return the signer address
+        if (v != 27 && v != 28) {
+            return (address(0));
+        } else {
+            return ecrecover(hash, v, r, s);
+        }
     }
 
-    // Divide the signature in r, s and v variables
+    /**
-    // ecrecover takes the signature parameters, and the only way to get them
+     * toEthSignedMessageHash
-    // currently is to use assembly.
+     * @dev prefix a bytes32 value with "\x19Ethereum Signed Message:"
-    // solium-disable-next-line security/no-inline-assembly
+     * and hash the result
-    assembly {
+     */
-      r := mload(add(signature, 0x20))
+    function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
-      s := mload(add(signature, 0x40))
+        // 32 is the length in bytes of hash,
-      v := byte(0, mload(add(signature, 0x60)))
+        // enforced by the type signature above
+        return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
     }
-
-    // Version of signature should be 27 or 28, but 0 and 1 are also possible versions
-    if (v < 27) {
-      v += 27;
-    }
-
-    // If the version is correct return the signer address
-    if (v != 27 && v != 28) {
-      return (address(0));
-    } else {
-      // solium-disable-next-line arg-overflow
-      return ecrecover(hash, v, r, s);
-    }
-  }
-
-  /**
-   * toEthSignedMessageHash
-   * @dev prefix a bytes32 value with "\x19Ethereum Signed Message:"
-   * and hash the result
-   */
-  function toEthSignedMessageHash(bytes32 hash)
-    internal
-    pure
-    returns (bytes32)
-  {
-    // 32 is the length in bytes of hash,
-    // enforced by the type signature above
-    return keccak256(
-      abi.encodePacked("\x19Ethereum Signed Message:\n32", hash)
-    );
-  }
 }

contracts/cryptography/MerkleProof.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title MerkleProof
@@ -6,37 +6,29 @@ pragma solidity ^0.4.24;
  * https://github.com/ameensol/merkle-tree-solidity/blob/master/src/MerkleProof.sol
  */
 library MerkleProof {
-  /**
+    /**
-   * @dev Verifies a Merkle proof proving the existence of a leaf in a Merkle tree. Assumes that each pair of leaves
+     * @dev Verifies a Merkle proof proving the existence of a leaf in a Merkle tree. Assumes that each pair of leaves
-   * and each pair of pre-images are sorted.
+     * and each pair of pre-images are sorted.
-   * @param proof Merkle proof containing sibling hashes on the branch from the leaf to the root of the Merkle tree
+     * @param proof Merkle proof containing sibling hashes on the branch from the leaf to the root of the Merkle tree
-   * @param root Merkle root
+     * @param root Merkle root
-   * @param leaf Leaf of Merkle tree
+     * @param leaf Leaf of Merkle tree
-   */
+     */
-  function verify(
+    function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) internal pure returns (bool) {
-    bytes32[] proof,
+        bytes32 computedHash = leaf;
-    bytes32 root,
-    bytes32 leaf
-  )
-    internal
-    pure
-    returns (bool)
-  {
-    bytes32 computedHash = leaf;
 
-    for (uint256 i = 0; i < proof.length; i++) {
+        for (uint256 i = 0; i < proof.length; i++) {
-      bytes32 proofElement = proof[i];
+            bytes32 proofElement = proof[i];
 
-      if (computedHash < proofElement) {
+            if (computedHash < proofElement) {
-        // Hash(current computed hash + current element of the proof)
+                // Hash(current computed hash + current element of the proof)
-        computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
+                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
-      } else {
+            } else {
-        // Hash(current element of the proof + current computed hash)
+                // Hash(current element of the proof + current computed hash)
-        computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
+                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
-      }
+            }
+        }
+
+        // Check if the computed hash (root) is equal to the provided root
+        return computedHash == root;
     }
-
-    // Check if the computed hash (root) is equal to the provided root
-    return computedHash == root;
-  }
 }

contracts/drafts/Counter.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title Counter
@@ -13,16 +13,12 @@ pragma solidity ^0.4.24;
  * so it's not something you have to worry about.)
  */
 library Counter {
+    struct Counter {
+        uint256 current; // default: 0
+    }
 
-  struct Counter {
+    function next(Counter storage index) internal returns (uint256) {
-    uint256 current; // default: 0
+        index.current += 1;
-  }
+        return index.current;
-
+    }
-  function next(Counter storage index)
-    internal
-    returns (uint256)
-  {
-    index.current += 1;
-    return index.current;
-  }
 }

contracts/drafts/ERC1046/TokenMetadata.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../token/ERC20/IERC20.sol";
 
@@ -6,22 +6,19 @@ import "../../token/ERC20/IERC20.sol";
  * @title ERC-1047 Token Metadata
  * @dev See https://eips.ethereum.org/EIPS/eip-1046
  * @dev tokenURI must respond with a URI that implements https://eips.ethereum.org/EIPS/eip-1047
- * @dev TODO - update https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC721/IERC721.sol#L17 when 1046 is finalized
  */
 contract ERC20TokenMetadata is IERC20 {
-  function tokenURI() external view returns (string);
+    function tokenURI() external view returns (string memory);
 }
 
 contract ERC20WithMetadata is ERC20TokenMetadata {
-  string private _tokenURI;
+    string private _tokenURI;
 
-  constructor(string tokenURI)
+    constructor (string memory tokenURI) public {
-    public
+        _tokenURI = tokenURI;
-  {
+    }
-    _tokenURI = tokenURI;
-  }
 
-  function tokenURI() external view returns (string) {
+    function tokenURI() external view returns (string memory) {
-    return _tokenURI;
+        return _tokenURI;
-  }
+    }
 }

contracts/drafts/ERC20Migrator.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../token/ERC20/ERC20Mintable.sol";
@@ -32,69 +32,69 @@ import "../math/Math.sol";
  * ```
  */
 contract ERC20Migrator {
-  using SafeERC20 for IERC20;
+    using SafeERC20 for IERC20;
 
-  /// Address of the old token contract
+    /// Address of the old token contract
-  IERC20 private _legacyToken;
+    IERC20 private _legacyToken;
 
-  /// Address of the new token contract
+    /// Address of the new token contract
-  ERC20Mintable private _newToken;
+    ERC20Mintable private _newToken;
 
-  /**
+    /**
-   * @param legacyToken address of the old token contract
+     * @param legacyToken address of the old token contract
-   */
+     */
-  constructor(IERC20 legacyToken) public {
+    constructor (IERC20 legacyToken) public {
-    require(legacyToken != address(0));
+        require(address(legacyToken) != address(0));
-    _legacyToken = legacyToken;
+        _legacyToken = legacyToken;
-  }
+    }
 
-  /**
+    /**
-   * @dev Returns the legacy token that is being migrated.
+     * @dev Returns the legacy token that is being migrated.
-   */
+     */
-  function legacyToken() public view returns (IERC20) {
+    function legacyToken() public view returns (IERC20) {
-    return _legacyToken;
+        return _legacyToken;
-  }
+    }
 
-  /**
+    /**
-   * @dev Returns the new token to which we are migrating.
+     * @dev Returns the new token to which we are migrating.
-   */
+     */
-  function newToken() public view returns (IERC20) {
+    function newToken() public view returns (IERC20) {
-    return _newToken;
+        return _newToken;
-  }
+    }
 
-  /**
+    /**
-   * @dev Begins the migration by setting which is the new token that will be
+     * @dev Begins the migration by setting which is the new token that will be
-   * minted. This contract must be a minter for the new token.
+     * minted. This contract must be a minter for the new token.
-   * @param newToken the token that will be minted
+     * @param newToken the token that will be minted
-   */
+     */
-  function beginMigration(ERC20Mintable newToken) public {
+    function beginMigration(ERC20Mintable newToken) public {
-    require(_newToken == address(0));
+        require(address(_newToken) == address(0));
-    require(newToken != address(0));
+        require(address(newToken) != address(0));
-    require(newToken.isMinter(this));
+        require(newToken.isMinter(address(this)));
 
-    _newToken = newToken;
+        _newToken = newToken;
-  }
+    }
 
-  /**
+    /**
-   * @dev Transfers part of an account's balance in the old token to this
+     * @dev Transfers part of an account's balance in the old token to this
-   * contract, and mints the same amount of new tokens for that account.
+     * contract, and mints the same amount of new tokens for that account.
-   * @param account whose tokens will be migrated
+     * @param account whose tokens will be migrated
-   * @param amount amount of tokens to be migrated
+     * @param amount amount of tokens to be migrated
-   */
+     */
-  function migrate(address account, uint256 amount) public {
+    function migrate(address account, uint256 amount) public {
-    _legacyToken.safeTransferFrom(account, this, amount);
+        _legacyToken.safeTransferFrom(account, address(this), amount);
-    _newToken.mint(account, amount);
+        _newToken.mint(account, amount);
-  }
+    }
 
-  /**
+    /**
-   * @dev Transfers all of an account's allowed balance in the old token to
+     * @dev Transfers all of an account's allowed balance in the old token to
-   * this contract, and mints the same amount of new tokens for that account.
+     * this contract, and mints the same amount of new tokens for that account.
-   * @param account whose tokens will be migrated
+     * @param account whose tokens will be migrated
-   */
+     */
-  function migrateAll(address account) public {
+    function migrateAll(address account) public {
-    uint256 balance = _legacyToken.balanceOf(account);
+        uint256 balance = _legacyToken.balanceOf(account);
-    uint256 allowance = _legacyToken.allowance(account, this);
+        uint256 allowance = _legacyToken.allowance(account, address(this));
-    uint256 amount = Math.min(balance, allowance);
+        uint256 amount = Math.min(balance, allowance);
-    migrate(account, amount);
+        migrate(account, amount);
-  }
+    }
 }

contracts/drafts/SignatureBouncer.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/roles/SignerRole.sol";
 import "../cryptography/ECDSA.sol";
@@ -35,112 +35,86 @@ import "../cryptography/ECDSA.sol";
  * See https://ethereum.stackexchange.com/a/50616 for more details.
  */
 contract SignatureBouncer is SignerRole {
-  using ECDSA for bytes32;
+    using ECDSA for bytes32;
 
-  // Function selectors are 4 bytes long, as documented in
+    // Function selectors are 4 bytes long, as documented in
-  // https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector
+    // https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector
-  uint256 private constant _METHOD_ID_SIZE = 4;
+    uint256 private constant _METHOD_ID_SIZE = 4;
-  // Signature size is 65 bytes (tightly packed v + r + s), but gets padded to 96 bytes
+    // Signature size is 65 bytes (tightly packed v + r + s), but gets padded to 96 bytes
-  uint256 private constant _SIGNATURE_SIZE = 96;
+    uint256 private constant _SIGNATURE_SIZE = 96;
 
-  constructor() internal {}
+    constructor () internal {
-
+        // solhint-disable-previous-line no-empty-blocks
-  /**
-   * @dev requires that a valid signature of a signer was provided
-   */
-  modifier onlyValidSignature(bytes signature)
-  {
-    require(_isValidSignature(msg.sender, signature));
-    _;
-  }
-
-  /**
-   * @dev requires that a valid signature with a specifed method of a signer was provided
-   */
-  modifier onlyValidSignatureAndMethod(bytes signature)
-  {
-    require(_isValidSignatureAndMethod(msg.sender, signature));
-    _;
-  }
-
-  /**
-   * @dev requires that a valid signature with a specifed method and params of a signer was provided
-   */
-  modifier onlyValidSignatureAndData(bytes signature)
-  {
-    require(_isValidSignatureAndData(msg.sender, signature));
-    _;
-  }
-
-  /**
-   * @dev is the signature of `this + sender` from a signer?
-   * @return bool
-   */
-  function _isValidSignature(address account, bytes signature)
-    internal
-    view
-    returns (bool)
-  {
-    return _isValidDataHash(
-      keccak256(abi.encodePacked(address(this), account)),
-      signature
-    );
-  }
-
-  /**
-   * @dev is the signature of `this + sender + methodId` from a signer?
-   * @return bool
-   */
-  function _isValidSignatureAndMethod(address account, bytes signature)
-    internal
-    view
-    returns (bool)
-  {
-    bytes memory data = new bytes(_METHOD_ID_SIZE);
-    for (uint i = 0; i < data.length; i++) {
-      data[i] = msg.data[i];
     }
-    return _isValidDataHash(
-      keccak256(abi.encodePacked(address(this), account, data)),
-      signature
-    );
-  }
 
-  /**
+    /**
-    * @dev is the signature of `this + sender + methodId + params(s)` from a signer?
+     * @dev requires that a valid signature of a signer was provided
-    * @notice the signature parameter of the method being validated must be the "last" parameter
+     */
-    * @return bool
+    modifier onlyValidSignature(bytes memory signature) {
-    */
+        require(_isValidSignature(msg.sender, signature));
-  function _isValidSignatureAndData(address account, bytes signature)
+        _;
-    internal
-    view
-    returns (bool)
-  {
-    require(msg.data.length > _SIGNATURE_SIZE);
-    bytes memory data = new bytes(msg.data.length - _SIGNATURE_SIZE);
-    for (uint i = 0; i < data.length; i++) {
-      data[i] = msg.data[i];
     }
-    return _isValidDataHash(
-      keccak256(abi.encodePacked(address(this), account, data)),
-      signature
-    );
-  }
 
-  /**
+    /**
-   * @dev internal function to convert a hash to an eth signed message
+     * @dev requires that a valid signature with a specifed method of a signer was provided
-   * and then recover the signature and check it against the signer role
+     */
-   * @return bool
+    modifier onlyValidSignatureAndMethod(bytes memory signature) {
-   */
+        require(_isValidSignatureAndMethod(msg.sender, signature));
-  function _isValidDataHash(bytes32 hash, bytes signature)
+        _;
-    internal
+    }
-    view
-    returns (bool)
-  {
-    address signer = hash
-      .toEthSignedMessageHash()
-      .recover(signature);
 
-    return signer != address(0) && isSigner(signer);
+    /**
-  }
+     * @dev requires that a valid signature with a specifed method and params of a signer was provided
+     */
+    modifier onlyValidSignatureAndData(bytes memory signature) {
+        require(_isValidSignatureAndData(msg.sender, signature));
+        _;
+    }
+
+    /**
+     * @dev is the signature of `this + sender` from a signer?
+     * @return bool
+     */
+    function _isValidSignature(address account, bytes memory signature) internal view returns (bool) {
+        return _isValidDataHash(keccak256(abi.encodePacked(address(this), account)), signature);
+    }
+
+    /**
+     * @dev is the signature of `this + sender + methodId` from a signer?
+     * @return bool
+     */
+    function _isValidSignatureAndMethod(address account, bytes memory signature) internal view returns (bool) {
+        bytes memory data = new bytes(_METHOD_ID_SIZE);
+        for (uint i = 0; i < data.length; i++) {
+            data[i] = msg.data[i];
+        }
+        return _isValidDataHash(keccak256(abi.encodePacked(address(this), account, data)), signature);
+    }
+
+    /**
+        * @dev is the signature of `this + sender + methodId + params(s)` from a signer?
+        * @notice the signature parameter of the method being validated must be the "last" parameter
+        * @return bool
+        */
+    function _isValidSignatureAndData(address account, bytes memory signature) internal view returns (bool) {
+        require(msg.data.length > _SIGNATURE_SIZE);
+
+        bytes memory data = new bytes(msg.data.length - _SIGNATURE_SIZE);
+        for (uint i = 0; i < data.length; i++) {
+            data[i] = msg.data[i];
+        }
+
+        return _isValidDataHash(keccak256(abi.encodePacked(address(this), account, data)), signature);
+    }
+
+    /**
+     * @dev internal function to convert a hash to an eth signed message
+     * and then recover the signature and check it against the signer role
+     * @return bool
+     */
+    function _isValidDataHash(bytes32 hash, bytes memory signature) internal view returns (bool) {
+        address signer = hash.toEthSignedMessageHash().recover(signature);
+
+        return signer != address(0) && isSigner(signer);
+    }
 }

contracts/drafts/SignedSafeMath.sol

@@ -0,0 +1,60 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title SignedSafeMath
+ * @dev Signed math operations with safety checks that revert on error
+ */
+library SignedSafeMath {
+    int256 constant private INT256_MIN = -2**255;
+
+    /**
+    * @dev Multiplies two signed integers, reverts on overflow.
+    */
+    function mul(int256 a, int256 b) internal pure returns (int256) {
+        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
+        // benefit is lost if 'b' is also tested.
+        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
+        if (a == 0) {
+            return 0;
+        }
+
+        require(!(a == -1 && b == INT256_MIN)); // This is the only case of overflow not detected by the check below
+
+        int256 c = a * b;
+        require(c / a == b);
+
+        return c;
+    }
+
+    /**
+    * @dev Integer division of two signed integers truncating the quotient, reverts on division by zero.
+    */
+    function div(int256 a, int256 b) internal pure returns (int256) {
+        require(b != 0); // Solidity only automatically asserts when dividing by 0
+        require(!(b == -1 && a == INT256_MIN)); // This is the only case of overflow
+
+        int256 c = a / b;
+
+        return c;
+    }
+
+    /**
+    * @dev Subtracts two signed integers, reverts on overflow.
+    */
+    function sub(int256 a, int256 b) internal pure returns (int256) {
+        int256 c = a - b;
+        require((b >= 0 && c <= a) || (b < 0 && c > a));
+
+        return c;
+    }
+
+    /**
+    * @dev Adds two signed integers, reverts on overflow.
+    */
+    function add(int256 a, int256 b) internal pure returns (int256) {
+        int256 c = a + b;
+        require((b >= 0 && c >= a) || (b < 0 && c < a));
+
+        return c;
+    }
+}

contracts/drafts/TokenVesting.sol

@@ -1,6 +1,4 @@
-/* solium-disable security/no-block-members */
+pragma solidity ^0.5.0;
-
-pragma solidity ^0.4.24;
 
 import "../token/ERC20/SafeERC20.sol";
 import "../ownership/Ownable.sol";
@@ -13,163 +11,162 @@ import "../math/SafeMath.sol";
  * owner.
  */
 contract TokenVesting is Ownable {
-  using SafeMath for uint256;
+    // The vesting schedule is time-based (i.e. using block timestamps as opposed to e.g. block numbers), and is
-  using SafeERC20 for IERC20;
+    // therefore sensitive to timestamp manipulation (which is something miners can do, to a certain degree). Therefore,
+    // it is recommended to avoid using short time durations (less than a minute). Typical vesting schemes, with a cliff
+    // period of a year and a duration of four years, are safe to use.
+    // solhint-disable not-rely-on-time
 
-  event TokensReleased(address token, uint256 amount);
+    using SafeMath for uint256;
-  event TokenVestingRevoked(address token);
+    using SafeERC20 for IERC20;
 
-  // beneficiary of tokens after they are released
+    event TokensReleased(address token, uint256 amount);
-  address private _beneficiary;
+    event TokenVestingRevoked(address token);
 
-  uint256 private _cliff;
+    // beneficiary of tokens after they are released
-  uint256 private _start;
+    address private _beneficiary;
-  uint256 private _duration;
 
-  bool private _revocable;
+    // Durations and timestamps are expressed in UNIX time, the same units as block.timestamp.
+    uint256 private _cliff;
+    uint256 private _start;
+    uint256 private _duration;
 
-  mapping (address => uint256) private _released;
+    bool private _revocable;
-  mapping (address => bool) private _revoked;
 
-  /**
+    mapping (address => uint256) private _released;
-   * @dev Creates a vesting contract that vests its balance of any ERC20 token to the
+    mapping (address => bool) private _revoked;
-   * beneficiary, gradually in a linear fashion until start + duration. By then all
-   * of the balance will have vested.
-   * @param beneficiary address of the beneficiary to whom vested tokens are transferred
-   * @param cliffDuration duration in seconds of the cliff in which tokens will begin to vest
-   * @param start the time (as Unix time) at which point vesting starts
-   * @param duration duration in seconds of the period in which the tokens will vest
-   * @param revocable whether the vesting is revocable or not
-   */
-  constructor(
-    address beneficiary,
-    uint256 start,
-    uint256 cliffDuration,
-    uint256 duration,
-    bool revocable
-  )
-    public
-  {
-    require(beneficiary != address(0));
-    require(cliffDuration <= duration);
-    require(duration > 0);
-    require(start.add(duration) > block.timestamp);
 
-    _beneficiary = beneficiary;
+    /**
-    _revocable = revocable;
+     * @dev Creates a vesting contract that vests its balance of any ERC20 token to the
-    _duration = duration;
+     * beneficiary, gradually in a linear fashion until start + duration. By then all
-    _cliff = start.add(cliffDuration);
+     * of the balance will have vested.
-    _start = start;
+     * @param beneficiary address of the beneficiary to whom vested tokens are transferred
-  }
+     * @param cliffDuration duration in seconds of the cliff in which tokens will begin to vest
+     * @param start the time (as Unix time) at which point vesting starts
+     * @param duration duration in seconds of the period in which the tokens will vest
+     * @param revocable whether the vesting is revocable or not
+     */
+    constructor (address beneficiary, uint256 start, uint256 cliffDuration, uint256 duration, bool revocable) public {
+        require(beneficiary != address(0));
+        require(cliffDuration <= duration);
+        require(duration > 0);
+        require(start.add(duration) > block.timestamp);
 
-  /**
+        _beneficiary = beneficiary;
-   * @return the beneficiary of the tokens.
+        _revocable = revocable;
-   */
+        _duration = duration;
-  function beneficiary() public view returns(address) {
+        _cliff = start.add(cliffDuration);
-    return _beneficiary;
+        _start = start;
-  }
+    }
-
+
-  /**
+    /**
-   * @return the cliff time of the token vesting.
+     * @return the beneficiary of the tokens.
-   */
+     */
-  function cliff() public view returns(uint256) {
+    function beneficiary() public view returns (address) {
-    return _cliff;
+        return _beneficiary;
-  }
+    }
-
+
-  /**
+    /**
-   * @return the start time of the token vesting.
+     * @return the cliff time of the token vesting.
-   */
+     */
-  function start() public view returns(uint256) {
+    function cliff() public view returns (uint256) {
-    return _start;
+        return _cliff;
-  }
+    }
-
+
-  /**
+    /**
-   * @return the duration of the token vesting.
+     * @return the start time of the token vesting.
-   */
+     */
-  function duration() public view returns(uint256) {
+    function start() public view returns (uint256) {
-    return _duration;
+        return _start;
-  }
+    }
-
+
-  /**
+    /**
-   * @return true if the vesting is revocable.
+     * @return the duration of the token vesting.
-   */
+     */
-  function revocable() public view returns(bool) {
+    function duration() public view returns (uint256) {
-    return _revocable;
+        return _duration;
-  }
+    }
-
+
-  /**
+    /**
-   * @return the amount of the token released.
+     * @return true if the vesting is revocable.
-   */
+     */
-  function released(address token) public view returns(uint256) {
+    function revocable() public view returns (bool) {
-    return _released[token];
+        return _revocable;
-  }
+    }
-
+
-  /**
+    /**
-   * @return true if the token is revoked.
+     * @return the amount of the token released.
-   */
+     */
-  function revoked(address token) public view returns(bool) {
+    function released(address token) public view returns (uint256) {
-    return _revoked[token];
+        return _released[token];
-  }
+    }
-
+
-  /**
+    /**
-   * @notice Transfers vested tokens to beneficiary.
+     * @return true if the token is revoked.
-   * @param token ERC20 token which is being vested
+     */
-   */
+    function revoked(address token) public view returns (bool) {
-  function release(IERC20 token) public {
+        return _revoked[token];
-    uint256 unreleased = _releasableAmount(token);
+    }
-
+
-    require(unreleased > 0);
+    /**
-
+     * @notice Transfers vested tokens to beneficiary.
-    _released[token] = _released[token].add(unreleased);
+     * @param token ERC20 token which is being vested
-
+     */
-    token.safeTransfer(_beneficiary, unreleased);
+    function release(IERC20 token) public {
-
+        uint256 unreleased = _releasableAmount(token);
-    emit TokensReleased(token, unreleased);
+
-  }
+        require(unreleased > 0);
-
+
-  /**
+        _released[address(token)] = _released[address(token)].add(unreleased);
-   * @notice Allows the owner to revoke the vesting. Tokens already vested
+
-   * remain in the contract, the rest are returned to the owner.
+        token.safeTransfer(_beneficiary, unreleased);
-   * @param token ERC20 token which is being vested
+
-   */
+        emit TokensReleased(address(token), unreleased);
-  function revoke(IERC20 token) public onlyOwner {
+    }
-    require(_revocable);
+
-    require(!_revoked[token]);
+    /**
-
+     * @notice Allows the owner to revoke the vesting. Tokens already vested
-    uint256 balance = token.balanceOf(address(this));
+     * remain in the contract, the rest are returned to the owner.
-
+     * @param token ERC20 token which is being vested
-    uint256 unreleased = _releasableAmount(token);
+     */
-    uint256 refund = balance.sub(unreleased);
+    function revoke(IERC20 token) public onlyOwner {
-
+        require(_revocable);
-    _revoked[token] = true;
+        require(!_revoked[address(token)]);
-
+
-    token.safeTransfer(owner(), refund);
+        uint256 balance = token.balanceOf(address(this));
-
+
-    emit TokenVestingRevoked(token);
+        uint256 unreleased = _releasableAmount(token);
-  }
+        uint256 refund = balance.sub(unreleased);
-
+
-  /**
+        _revoked[address(token)] = true;
-   * @dev Calculates the amount that has already vested but hasn't been released yet.
+
-   * @param token ERC20 token which is being vested
+        token.safeTransfer(owner(), refund);
-   */
+
-  function _releasableAmount(IERC20 token) private view returns (uint256) {
+        emit TokenVestingRevoked(address(token));
-    return _vestedAmount(token).sub(_released[token]);
+    }
-  }
+
-
+    /**
-  /**
+     * @dev Calculates the amount that has already vested but hasn't been released yet.
-   * @dev Calculates the amount that has already vested.
+     * @param token ERC20 token which is being vested
-   * @param token ERC20 token which is being vested
+     */
-   */
+    function _releasableAmount(IERC20 token) private view returns (uint256) {
-  function _vestedAmount(IERC20 token) private view returns (uint256) {
+        return _vestedAmount(token).sub(_released[address(token)]);
-    uint256 currentBalance = token.balanceOf(this);
+    }
-    uint256 totalBalance = currentBalance.add(_released[token]);
+
-
+    /**
-    if (block.timestamp < _cliff) {
+     * @dev Calculates the amount that has already vested.
-      return 0;
+     * @param token ERC20 token which is being vested
-    } else if (block.timestamp >= _start.add(_duration) || _revoked[token]) {
+     */
-      return totalBalance;
+    function _vestedAmount(IERC20 token) private view returns (uint256) {
-    } else {
+        uint256 currentBalance = token.balanceOf(address(this));
-      return totalBalance.mul(block.timestamp.sub(_start)).div(_duration);
+        uint256 totalBalance = currentBalance.add(_released[address(token)]);
+
+        if (block.timestamp < _cliff) {
+            return 0;
+        } else if (block.timestamp >= _start.add(_duration) || _revoked[address(token)]) {
+            return totalBalance;
+        } else {
+            return totalBalance.mul(block.timestamp.sub(_start)).div(_duration);
+        }
     }
-  }
 }

contracts/examples/SampleCrowdsale.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../crowdsale/validation/CappedCrowdsale.sol";
 import "../crowdsale/distribution/RefundableCrowdsale.sol";
@@ -12,7 +12,9 @@ import "../token/ERC20/ERC20Detailed.sol";
  * It is meant to be used in a crowdsale contract.
  */
 contract SampleCrowdsaleToken is ERC20Mintable, ERC20Detailed {
-  constructor() public ERC20Detailed("Sample Crowdsale Token", "SCT", 18) {}
+    constructor () public ERC20Detailed("Sample Crowdsale Token", "SCT", 18) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }
 
 /**
@@ -28,30 +30,24 @@ contract SampleCrowdsaleToken is ERC20Mintable, ERC20Detailed {
  * After adding multiple features it's good practice to run integration tests
  * to ensure that subcontracts works together as intended.
  */
-// XXX There doesn't seem to be a way to split this line that keeps solium
-// happy. See:
-// https://github.com/duaraghav8/Solium/issues/205
-// --elopio - 2018-05-10
-// solium-disable-next-line max-len
 contract SampleCrowdsale is CappedCrowdsale, RefundableCrowdsale, MintedCrowdsale {
-
+    constructor (
-  constructor(
+        uint256 openingTime,
-    uint256 openingTime,
+        uint256 closingTime,
-    uint256 closingTime,
+        uint256 rate,
-    uint256 rate,
+        address payable wallet,
-    address wallet,
+        uint256 cap,
-    uint256 cap,
+        ERC20Mintable token,
-    ERC20Mintable token,
+        uint256 goal
-    uint256 goal
+    )
-  )
+        public
-    public
+        Crowdsale(rate, wallet, token)
-    Crowdsale(rate, wallet, token)
+        CappedCrowdsale(cap)
-    CappedCrowdsale(cap)
+        TimedCrowdsale(openingTime, closingTime)
-    TimedCrowdsale(openingTime, closingTime)
+        RefundableCrowdsale(goal)
-    RefundableCrowdsale(goal)
+    {
-  {
+        //As goal needs to be met for a successful crowdsale
-    //As goal needs to be met for a successful crowdsale
+        //the value needs to less or equal than a cap which is limit for accepted funds
-    //the value needs to less or equal than a cap which is limit for accepted funds
+        require(goal <= cap);
-    require(goal <= cap);
+    }
-  }
 }

contracts/examples/SimpleToken.sol

@@ -1,6 +1,7 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/ERC20Detailed.sol";
 
 /**
  * @title SimpleToken
@@ -8,19 +9,14 @@ import "../token/ERC20/ERC20.sol";
  * Note they can later distribute these tokens as they wish using `transfer` and other
  * `ERC20` functions.
  */
-contract SimpleToken is ERC20 {
+contract SimpleToken is ERC20, ERC20Detailed {
-
+    uint8 public constant DECIMALS = 18;
-  string public constant name = "SimpleToken";
+    uint256 public constant INITIAL_SUPPLY = 10000 * (10 ** uint256(DECIMALS));
-  string public constant symbol = "SIM";
-  uint8 public constant decimals = 18;
-
-  uint256 public constant INITIAL_SUPPLY = 10000 * (10 ** uint256(decimals));
-
-  /**
-   * @dev Constructor that gives msg.sender all of existing tokens.
-   */
-  constructor() public {
-    _mint(msg.sender, INITIAL_SUPPLY);
-  }
 
+    /**
+     * @dev Constructor that gives msg.sender all of existing tokens.
+     */
+    constructor () public ERC20Detailed("SimpleToken", "SIM", DECIMALS) {
+        _mint(msg.sender, INITIAL_SUPPLY);
+    }
 }

contracts/introspection/ERC165.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "./IERC165.sol";
 
@@ -8,46 +8,37 @@ import "./IERC165.sol";
  * @dev Implements ERC165 using a lookup table.
  */
 contract ERC165 is IERC165 {
+    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
+    /**
+     * 0x01ffc9a7 ===
+     *     bytes4(keccak256('supportsInterface(bytes4)'))
+     */
 
-  bytes4 private constant _InterfaceId_ERC165 = 0x01ffc9a7;
+    /**
-  /**
+     * @dev a mapping of interface id to whether or not it's supported
-   * 0x01ffc9a7 ===
+     */
-   *   bytes4(keccak256('supportsInterface(bytes4)'))
+    mapping(bytes4 => bool) private _supportedInterfaces;
-   */
 
-  /**
+    /**
-   * @dev a mapping of interface id to whether or not it's supported
+     * @dev A contract implementing SupportsInterfaceWithLookup
-   */
+     * implement ERC165 itself
-  mapping(bytes4 => bool) private _supportedInterfaces;
+     */
+    constructor () internal {
+        _registerInterface(_INTERFACE_ID_ERC165);
+    }
 
-  /**
+    /**
-   * @dev A contract implementing SupportsInterfaceWithLookup
+     * @dev implement supportsInterface(bytes4) using a lookup table
-   * implement ERC165 itself
+     */
-   */
+    function supportsInterface(bytes4 interfaceId) external view returns (bool) {
-  constructor()
+        return _supportedInterfaces[interfaceId];
-    internal
+    }
-  {
-    _registerInterface(_InterfaceId_ERC165);
-  }
 
-  /**
+    /**
-   * @dev implement supportsInterface(bytes4) using a lookup table
+     * @dev internal method for registering an interface
-   */
+     */
-  function supportsInterface(bytes4 interfaceId)
+    function _registerInterface(bytes4 interfaceId) internal {
-    external
+        require(interfaceId != 0xffffffff);
-    view
+        _supportedInterfaces[interfaceId] = true;
-    returns (bool)
+    }
-  {
-    return _supportedInterfaces[interfaceId];
-  }
-
-  /**
-   * @dev internal method for registering an interface
-   */
-  function _registerInterface(bytes4 interfaceId)
-    internal
-  {
-    require(interfaceId != 0xffffffff);
-    _supportedInterfaces[interfaceId] = true;
-  }
 }

contracts/introspection/ERC165Checker.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title ERC165Checker
@@ -6,141 +6,118 @@ pragma solidity ^0.4.24;
  * https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
  */
 library ERC165Checker {
-  // As per the EIP-165 spec, no interface should ever match 0xffffffff
+    // As per the EIP-165 spec, no interface should ever match 0xffffffff
-  bytes4 private constant _InterfaceId_Invalid = 0xffffffff;
+    bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;
 
-  bytes4 private constant _InterfaceId_ERC165 = 0x01ffc9a7;
+    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
-  /**
+    /**
-   * 0x01ffc9a7 ===
+     * 0x01ffc9a7 ===
-   *   bytes4(keccak256('supportsInterface(bytes4)'))
+     *     bytes4(keccak256('supportsInterface(bytes4)'))
-   */
+     */
 
-  /**
+    /**
-   * @notice Query if a contract supports ERC165
+     * @notice Query if a contract supports ERC165
-   * @param account The address of the contract to query for support of ERC165
+     * @param account The address of the contract to query for support of ERC165
-   * @return true if the contract at account implements ERC165
+     * @return true if the contract at account implements ERC165
-   */
+     */
-  function _supportsERC165(address account)
+    function _supportsERC165(address account) internal view returns (bool) {
-    internal
+        // Any contract that implements ERC165 must explicitly indicate support of
-    view
+        // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
-    returns (bool)
+        return _supportsERC165Interface(account, _INTERFACE_ID_ERC165) &&
-  {
+            !_supportsERC165Interface(account, _INTERFACE_ID_INVALID);
-    // Any contract that implements ERC165 must explicitly indicate support of
-    // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
-    return _supportsERC165Interface(account, _InterfaceId_ERC165) &&
-      !_supportsERC165Interface(account, _InterfaceId_Invalid);
-  }
-
-  /**
-   * @notice Query if a contract implements an interface, also checks support of ERC165
-   * @param account The address of the contract to query for support of an interface
-   * @param interfaceId The interface identifier, as specified in ERC-165
-   * @return true if the contract at account indicates support of the interface with
-   * identifier interfaceId, false otherwise
-   * @dev Interface identification is specified in ERC-165.
-   */
-  function _supportsInterface(address account, bytes4 interfaceId)
-    internal
-    view
-    returns (bool)
-  {
-    // query support of both ERC165 as per the spec and support of _interfaceId
-    return _supportsERC165(account) &&
-      _supportsERC165Interface(account, interfaceId);
-  }
-
-  /**
-   * @notice Query if a contract implements interfaces, also checks support of ERC165
-   * @param account The address of the contract to query for support of an interface
-   * @param interfaceIds A list of interface identifiers, as specified in ERC-165
-   * @return true if the contract at account indicates support all interfaces in the
-   * interfaceIds list, false otherwise
-   * @dev Interface identification is specified in ERC-165.
-   */
-  function _supportsAllInterfaces(address account, bytes4[] interfaceIds)
-    internal
-    view
-    returns (bool)
-  {
-    // query support of ERC165 itself
-    if (!_supportsERC165(account)) {
-      return false;
     }
 
-    // query support of each interface in _interfaceIds
+    /**
-    for (uint256 i = 0; i < interfaceIds.length; i++) {
+     * @notice Query if a contract implements an interface, also checks support of ERC165
-      if (!_supportsERC165Interface(account, interfaceIds[i])) {
+     * @param account The address of the contract to query for support of an interface
-        return false;
+     * @param interfaceId The interface identifier, as specified in ERC-165
-      }
+     * @return true if the contract at account indicates support of the interface with
+     * identifier interfaceId, false otherwise
+     * @dev Interface identification is specified in ERC-165.
+     */
+    function _supportsInterface(address account, bytes4 interfaceId) internal view returns (bool) {
+        // query support of both ERC165 as per the spec and support of _interfaceId
+        return _supportsERC165(account) &&
+            _supportsERC165Interface(account, interfaceId);
     }
 
-    // all interfaces supported
+    /**
-    return true;
+     * @notice Query if a contract implements interfaces, also checks support of ERC165
-  }
+     * @param account The address of the contract to query for support of an interface
+     * @param interfaceIds A list of interface identifiers, as specified in ERC-165
+     * @return true if the contract at account indicates support all interfaces in the
+     * interfaceIds list, false otherwise
+     * @dev Interface identification is specified in ERC-165.
+     */
+    function _supportsAllInterfaces(address account, bytes4[] memory interfaceIds) internal view returns (bool) {
+        // query support of ERC165 itself
+        if (!_supportsERC165(account)) {
+            return false;
+        }
 
-  /**
+        // query support of each interface in _interfaceIds
-   * @notice Query if a contract implements an interface, does not check ERC165 support
+        for (uint256 i = 0; i < interfaceIds.length; i++) {
-   * @param account The address of the contract to query for support of an interface
+            if (!_supportsERC165Interface(account, interfaceIds[i])) {
-   * @param interfaceId The interface identifier, as specified in ERC-165
+                return false;
-   * @return true if the contract at account indicates support of the interface with
+            }
-   * identifier interfaceId, false otherwise
+        }
-   * @dev Assumes that account contains a contract that supports ERC165, otherwise
-   * the behavior of this method is undefined. This precondition can be checked
-   * with the `supportsERC165` method in this library.
-   * Interface identification is specified in ERC-165.
-   */
-  function _supportsERC165Interface(address account, bytes4 interfaceId)
-    private
-    view
-    returns (bool)
-  {
-    // success determines whether the staticcall succeeded and result determines
-    // whether the contract at account indicates support of _interfaceId
-    (bool success, bool result) = _callERC165SupportsInterface(
-      account, interfaceId);
 
-    return (success && result);
+        // all interfaces supported
-  }
+        return true;
-
+    }
-  /**
+
-   * @notice Calls the function with selector 0x01ffc9a7 (ERC165) and suppresses throw
+    /**
-   * @param account The address of the contract to query for support of an interface
+     * @notice Query if a contract implements an interface, does not check ERC165 support
-   * @param interfaceId The interface identifier, as specified in ERC-165
+     * @param account The address of the contract to query for support of an interface
-   * @return success true if the STATICCALL succeeded, false otherwise
+     * @param interfaceId The interface identifier, as specified in ERC-165
-   * @return result true if the STATICCALL succeeded and the contract at account
+     * @return true if the contract at account indicates support of the interface with
-   * indicates support of the interface with identifier interfaceId, false otherwise
+     * identifier interfaceId, false otherwise
-   */
+     * @dev Assumes that account contains a contract that supports ERC165, otherwise
-  function _callERC165SupportsInterface(
+     * the behavior of this method is undefined. This precondition can be checked
-    address account,
+     * with the `supportsERC165` method in this library.
-    bytes4 interfaceId
+     * Interface identification is specified in ERC-165.
-  )
+     */
-    private
+    function _supportsERC165Interface(address account, bytes4 interfaceId) private view returns (bool) {
-    view
+        // success determines whether the staticcall succeeded and result determines
-    returns (bool success, bool result)
+        // whether the contract at account indicates support of _interfaceId
-  {
+        (bool success, bool result) = _callERC165SupportsInterface(account, interfaceId);
-    bytes memory encodedParams = abi.encodeWithSelector(
+
-      _InterfaceId_ERC165,
+        return (success && result);
-      interfaceId
+    }
-    );
+
-
+    /**
-    // solium-disable-next-line security/no-inline-assembly
+     * @notice Calls the function with selector 0x01ffc9a7 (ERC165) and suppresses throw
-    assembly {
+     * @param account The address of the contract to query for support of an interface
-      let encodedParams_data := add(0x20, encodedParams)
+     * @param interfaceId The interface identifier, as specified in ERC-165
-      let encodedParams_size := mload(encodedParams)
+     * @return success true if the STATICCALL succeeded, false otherwise
-
+     * @return result true if the STATICCALL succeeded and the contract at account
-      let output := mload(0x40)  // Find empty storage location using "free memory pointer"
+     * indicates support of the interface with identifier interfaceId, false otherwise
-      mstore(output, 0x0)
+     */
-
+    function _callERC165SupportsInterface(address account, bytes4 interfaceId)
-      success := staticcall(
+        private
-        30000,                 // 30k gas
+        view
-        account,              // To addr
+        returns (bool success, bool result)
-        encodedParams_data,
+    {
-        encodedParams_size,
+        bytes memory encodedParams = abi.encodeWithSelector(_INTERFACE_ID_ERC165, interfaceId);
-        output,
+
-        0x20                   // Outputs are 32 bytes long
+        // solhint-disable-next-line no-inline-assembly
-      )
+        assembly {
-
+            let encodedParams_data := add(0x20, encodedParams)
-      result := mload(output)  // Load the result
+            let encodedParams_size := mload(encodedParams)
+
+            let output := mload(0x40)    // Find empty storage location using "free memory pointer"
+            mstore(output, 0x0)
+
+            success := staticcall(
+                30000,                                 // 30k gas
+                account,                            // To addr
+                encodedParams_data,
+                encodedParams_size,
+                output,
+                0x20                                     // Outputs are 32 bytes long
+            )
+
+            result := mload(output)    // Load the result
+        }
     }
-  }
 }

contracts/introspection/IERC165.sol

@@ -1,19 +1,15 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title IERC165
  * @dev https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
  */
 interface IERC165 {
-
+    /**
-  /**
+     * @notice Query if a contract implements an interface
-   * @notice Query if a contract implements an interface
+     * @param interfaceId The interface identifier, as specified in ERC-165
-   * @param interfaceId The interface identifier, as specified in ERC-165
+     * @dev Interface identification is specified in ERC-165. This function
-   * @dev Interface identification is specified in ERC-165. This function
+     * uses less than 30,000 gas.
-   * uses less than 30,000 gas.
+     */
-   */
+    function supportsInterface(bytes4 interfaceId) external view returns (bool);
-  function supportsInterface(bytes4 interfaceId)
-    external
-    view
-    returns (bool);
 }

contracts/lifecycle/Pausable.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/roles/PauserRole.sol";
 
@@ -7,51 +7,51 @@ import "../access/roles/PauserRole.sol";
  * @dev Base contract which allows children to implement an emergency stop mechanism.
  */
 contract Pausable is PauserRole {
-  event Paused(address account);
+    event Paused(address account);
-  event Unpaused(address account);
+    event Unpaused(address account);
 
-  bool private _paused;
+    bool private _paused;
 
-  constructor() internal {
+    constructor () internal {
-    _paused = false;
+        _paused = false;
-  }
+    }
 
-  /**
+    /**
-   * @return true if the contract is paused, false otherwise.
+     * @return true if the contract is paused, false otherwise.
-   */
+     */
-  function paused() public view returns(bool) {
+    function paused() public view returns (bool) {
-    return _paused;
+        return _paused;
-  }
+    }
 
-  /**
+    /**
-   * @dev Modifier to make a function callable only when the contract is not paused.
+     * @dev Modifier to make a function callable only when the contract is not paused.
-   */
+     */
-  modifier whenNotPaused() {
+    modifier whenNotPaused() {
-    require(!_paused);
+        require(!_paused);
-    _;
+        _;
-  }
+    }
 
-  /**
+    /**
-   * @dev Modifier to make a function callable only when the contract is paused.
+     * @dev Modifier to make a function callable only when the contract is paused.
-   */
+     */
-  modifier whenPaused() {
+    modifier whenPaused() {
-    require(_paused);
+        require(_paused);
-    _;
+        _;
-  }
+    }
 
-  /**
+    /**
-   * @dev called by the owner to pause, triggers stopped state
+     * @dev called by the owner to pause, triggers stopped state
-   */
+     */
-  function pause() public onlyPauser whenNotPaused {
+    function pause() public onlyPauser whenNotPaused {
-    _paused = true;
+        _paused = true;
-    emit Paused(msg.sender);
+        emit Paused(msg.sender);
-  }
+    }
 
-  /**
+    /**
-   * @dev called by the owner to unpause, returns to normal state
+     * @dev called by the owner to unpause, returns to normal state
-   */
+     */
-  function unpause() public onlyPauser whenPaused {
+    function unpause() public onlyPauser whenPaused {
-    _paused = false;
+        _paused = false;
-    emit Unpaused(msg.sender);
+        emit Unpaused(msg.sender);
-  }
+    }
 }

contracts/math/Math.sol

@@ -1,31 +1,31 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title Math
  * @dev Assorted math operations
  */
 library Math {
-  /**
+    /**
-  * @dev Returns the largest of two numbers.
+    * @dev Returns the largest of two numbers.
-  */
+    */
-  function max(uint256 a, uint256 b) internal pure returns (uint256) {
+    function max(uint256 a, uint256 b) internal pure returns (uint256) {
-    return a >= b ? a : b;
+        return a >= b ? a : b;
-  }
+    }
 
-  /**
+    /**
-  * @dev Returns the smallest of two numbers.
+    * @dev Returns the smallest of two numbers.
-  */
+    */
-  function min(uint256 a, uint256 b) internal pure returns (uint256) {
+    function min(uint256 a, uint256 b) internal pure returns (uint256) {
-    return a < b ? a : b;
+        return a < b ? a : b;
-  }
+    }
 
-  /**
+    /**
-  * @dev Calculates the average of two numbers. Since these are integers,
+    * @dev Calculates the average of two numbers. Since these are integers,
-  * averages of an even and odd number cannot be represented, and will be
+    * averages of an even and odd number cannot be represented, and will be
-  * rounded down.
+    * rounded down.
-  */
+    */
-  function average(uint256 a, uint256 b) internal pure returns (uint256) {
+    function average(uint256 a, uint256 b) internal pure returns (uint256) {
-    // (a + b) / 2 can overflow, so we distribute
+        // (a + b) / 2 can overflow, so we distribute
-    return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
+        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
-  }
+    }
 }

contracts/math/SafeMath.sol

@@ -1,65 +1,65 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 /**
  * @title SafeMath
- * @dev Math operations with safety checks that revert on error
+ * @dev Unsigned math operations with safety checks that revert on error
  */
 library SafeMath {
+    /**
+    * @dev Multiplies two unsigned integers, reverts on overflow.
+    */
+    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
+        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
+        // benefit is lost if 'b' is also tested.
+        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
+        if (a == 0) {
+            return 0;
+        }
 
-  /**
+        uint256 c = a * b;
-  * @dev Multiplies two numbers, reverts on overflow.
+        require(c / a == b);
-  */
+
-  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
+        return c;
-    // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
-    // benefit is lost if 'b' is also tested.
-    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
-    if (a == 0) {
-      return 0;
     }
 
-    uint256 c = a * b;
+    /**
-    require(c / a == b);
+    * @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
+    */
+    function div(uint256 a, uint256 b) internal pure returns (uint256) {
+        // Solidity only automatically asserts when dividing by 0
+        require(b > 0);
+        uint256 c = a / b;
+        // assert(a == b * c + a % b); // There is no case in which this doesn't hold
 
-    return c;
+        return c;
-  }
+    }
 
-  /**
+    /**
-  * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
+    * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
-  */
+    */
-  function div(uint256 a, uint256 b) internal pure returns (uint256) {
+    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
-    require(b > 0); // Solidity only automatically asserts when dividing by 0
+        require(b <= a);
-    uint256 c = a / b;
+        uint256 c = a - b;
-    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
 
-    return c;
+        return c;
-  }
+    }
 
-  /**
+    /**
-  * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
+    * @dev Adds two unsigned integers, reverts on overflow.
-  */
+    */
-  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
+    function add(uint256 a, uint256 b) internal pure returns (uint256) {
-    require(b <= a);
+        uint256 c = a + b;
-    uint256 c = a - b;
+        require(c >= a);
 
-    return c;
+        return c;
-  }
+    }
 
-  /**
+    /**
-  * @dev Adds two numbers, reverts on overflow.
+    * @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
-  */
+    * reverts when dividing by zero.
-  function add(uint256 a, uint256 b) internal pure returns (uint256) {
+    */
-    uint256 c = a + b;
+    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
-    require(c >= a);
+        require(b != 0);
-
+        return a % b;
-    return c;
+    }
-  }
-
-  /**
-  * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
-  * reverts when dividing by zero.
-  */
-  function mod(uint256 a, uint256 b) internal pure returns (uint256) {
-    require(b != 0);
-    return a % b;
-  }
 }

contracts/mocks/Acknowledger.sol

@@ -0,0 +1,19 @@
+pragma solidity ^0.5.0;
+
+contract Acknowledger {
+    event AcknowledgeFoo(uint256 a);
+    event AcknowledgeBarSingle(uint256 a);
+    event AcknowledgeBarDouble(uint256 a, uint256 b);
+
+    function foo(uint256 a) public {
+        emit AcknowledgeFoo(a);
+    }
+
+    function bar(uint256 a) public {
+        emit AcknowledgeBarSingle(a);
+    }
+
+    function bar(uint256 a, uint256 b) public {
+        emit AcknowledgeBarDouble(a, b);
+    }
+}

contracts/mocks/AddressImpl.sol

@@ -1,14 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../utils/Address.sol";
 
 contract AddressImpl {
-  function isContract(address account)
+    function isContract(address account) external view returns (bool) {
-    external
+        return Address.isContract(account);
-    view
+    }
-    returns (bool)
-  {
-    return Address.isContract(account); 
-  }
-  
 }

contracts/mocks/AllowanceCrowdsaleImpl.sol

@@ -1,20 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../crowdsale/emission/AllowanceCrowdsale.sol";
 
 contract AllowanceCrowdsaleImpl is AllowanceCrowdsale {
-
+    constructor (uint256 rate, address payable wallet, IERC20 token, address tokenWallet)
-  constructor (
+        public
-    uint256 rate,
+        Crowdsale(rate, wallet, token)
-    address wallet,
+        AllowanceCrowdsale(tokenWallet)
-    IERC20 token,
+    {
-    address tokenWallet
+        // solhint-disable-previous-line no-empty-blocks
-  )
+    }
-    public
-    Crowdsale(rate, wallet, token)
-    AllowanceCrowdsale(tokenWallet)
-  {
-  }
-
 }

contracts/mocks/ArraysImpl.sol

@@ -1,18 +1,17 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../utils/Arrays.sol";
 
 contract ArraysImpl {
+    using Arrays for uint256[];
 
-  using Arrays for uint256[];
+    uint256[] private array;
 
-  uint256[] private array;
+    constructor (uint256[] memory _array) public {
+        array = _array;
+    }
 
-  constructor(uint256[] _array) public {
+    function findUpperBound(uint256 _element) external view returns (uint256) {
-    array = _array;
+        return array.findUpperBound(_element);
-  }
+    }
-
-  function findUpperBound(uint256 _element) external view returns (uint256) {
-    return array.findUpperBound(_element);
-  }
 }

contracts/mocks/CappedCrowdsaleImpl.sol

@@ -1,20 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../crowdsale/validation/CappedCrowdsale.sol";
 
 contract CappedCrowdsaleImpl is CappedCrowdsale {
-
+    constructor (uint256 rate, address payable wallet, IERC20 token, uint256 cap)
-  constructor (
+        public
-    uint256 rate,
+        Crowdsale(rate, wallet, token)
-    address wallet,
+        CappedCrowdsale(cap)
-    IERC20 token,
+    {
-    uint256 cap
+        // solhint-disable-previous-line no-empty-blocks
-  )
+    }
-    public
-    Crowdsale(rate, wallet, token)
-    CappedCrowdsale(cap)
-  {
-  }
-
 }

contracts/mocks/CapperRoleMock.sol

@@ -1,17 +1,18 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/roles/CapperRole.sol";
 
 contract CapperRoleMock is CapperRole {
-  function removeCapper(address account) public {
+    function removeCapper(address account) public {
-    _removeCapper(account);
+        _removeCapper(account);
-  }
+    }
 
-  function onlyCapperMock() public view onlyCapper {
+    function onlyCapperMock() public view onlyCapper {
-  }
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  // Causes a compilation error if super._removeCapper is not internal
+    // Causes a compilation error if super._removeCapper is not internal
-  function _removeCapper(address account) internal {
+    function _removeCapper(address account) internal {
-    super._removeCapper(account);
+        super._removeCapper(account);
-  }
+    }
 }

contracts/mocks/ConditionalEscrowMock.sol

@@ -1,16 +1,16 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../payment/escrow/ConditionalEscrow.sol";
 
 // mock class using ConditionalEscrow
 contract ConditionalEscrowMock is ConditionalEscrow {
-  mapping(address => bool) private _allowed;
+    mapping(address => bool) private _allowed;
 
-  function setAllowed(address payee, bool allowed) public {
+    function setAllowed(address payee, bool allowed) public {
-    _allowed[payee] = allowed;
+        _allowed[payee] = allowed;
-  }
+    }
 
-  function withdrawalAllowed(address payee) public view returns (bool) {
+    function withdrawalAllowed(address payee) public view returns (bool) {
-    return _allowed[payee];
+        return _allowed[payee];
-  }
+    }
 }

contracts/mocks/CounterImpl.sol

@@ -1,20 +1,17 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../drafts/Counter.sol";
 
 contract CounterImpl {
-  using Counter for Counter.Counter;
+    using Counter for Counter.Counter;
 
-  uint256 public theId;
+    uint256 public theId;
 
-  // use whatever key you want to track your counters
+    // use whatever key you want to track your counters
-  mapping(string => Counter.Counter) private _counters;
+    mapping(string => Counter.Counter) private _counters;
 
-  function doThing(string key)
+    function doThing(string memory key) public returns (uint256) {
-    public
+        theId = _counters[key].next();
-    returns (uint256)
+        return theId;
-  {
+    }
-    theId = _counters[key].next();
-    return theId;
-  }
 }

contracts/mocks/CrowdsaleMock.sol

@@ -1,9 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../crowdsale/Crowdsale.sol";
 
 contract CrowdsaleMock is Crowdsale {
-  constructor(uint256 rate, address wallet, IERC20 token) public
+    constructor (uint256 rate, address payable wallet, IERC20 token) public Crowdsale(rate, wallet, token) {
-    Crowdsale(rate, wallet, token) {
+        // solhint-disable-previous-line no-empty-blocks
-  }
+    }
 }

contracts/mocks/DetailedERC20Mock.sol

@@ -1,15 +1,13 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20.sol";
 import "../token/ERC20/ERC20Detailed.sol";
 
 contract ERC20DetailedMock is ERC20, ERC20Detailed {
-  constructor(
+    constructor (string memory name, string memory symbol, uint8 decimals)
-    string name,
+        public
-    string symbol,
+        ERC20Detailed(name, symbol, decimals)
-    uint8 decimals
+    {
-  )
+        // solhint-disable-previous-line no-empty-blocks
-    ERC20Detailed(name, symbol, decimals)
+    }
-    public
-  {}
 }

contracts/mocks/ECDSAMock.sol

@@ -1,23 +1,15 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../cryptography/ECDSA.sol";
 
 contract ECDSAMock {
-  using ECDSA for bytes32;
+    using ECDSA for bytes32;
 
-  function recover(bytes32 hash, bytes signature)
+    function recover(bytes32 hash, bytes memory signature) public pure returns (address) {
-    public
+        return hash.recover(signature);
-    pure
+    }
-    returns (address)
-  {
-    return hash.recover(signature);
-  }
 
-  function toEthSignedMessageHash(bytes32 hash)
+    function toEthSignedMessageHash(bytes32 hash) public pure returns (bytes32) {
-    public
+        return hash.toEthSignedMessageHash();
-    pure
+    }
-    returns (bytes32)
-  {
-    return hash.toEthSignedMessageHash();
-  }
 }

contracts/mocks/ERC165/ERC165InterfacesSupported.sol

@@ -1,66 +1,56 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../introspection/IERC165.sol";
 
 /**
  * https://github.com/ethereum/EIPs/blob/master/EIPS/eip-214.md#specification
- * > Any attempts to make state-changing operations inside an execution instance with STATIC set to true will instead throw an exception.
+ * > Any attempts to make state-changing operations inside an execution instance with STATIC set to true will instead
+ * throw an exception.
  * > These operations include [...], LOG0, LOG1, LOG2, [...]
  *
  * therefore, because this contract is staticcall'd we need to not emit events (which is how solidity-coverage works)
  * solidity-coverage ignores the /mocks folder, so we duplicate its implementation here to avoid instrumenting it
  */
 contract SupportsInterfaceWithLookupMock is IERC165 {
+    bytes4 public constant INTERFACE_ID_ERC165 = 0x01ffc9a7;
+    /**
+     * 0x01ffc9a7 ===
+     *     bytes4(keccak256('supportsInterface(bytes4)'))
+     */
 
-  bytes4 public constant InterfaceId_ERC165 = 0x01ffc9a7;
+    /**
-  /**
+     * @dev a mapping of interface id to whether or not it's supported
-   * 0x01ffc9a7 ===
+     */
-   *   bytes4(keccak256('supportsInterface(bytes4)'))
+    mapping(bytes4 => bool) private _supportedInterfaces;
-   */
 
-  /**
+    /**
-   * @dev a mapping of interface id to whether or not it's supported
+     * @dev A contract implementing SupportsInterfaceWithLookup
-   */
+     * implement ERC165 itself
-  mapping(bytes4 => bool) private _supportedInterfaces;
+     */
+    constructor () public {
+        _registerInterface(INTERFACE_ID_ERC165);
+    }
 
-  /**
+    /**
-   * @dev A contract implementing SupportsInterfaceWithLookup
+     * @dev implement supportsInterface(bytes4) using a lookup table
-   * implement ERC165 itself
+     */
-   */
+    function supportsInterface(bytes4 interfaceId) external view returns (bool) {
-  constructor()
+        return _supportedInterfaces[interfaceId];
-    public
+    }
-  {
-    _registerInterface(InterfaceId_ERC165);
-  }
 
-  /**
+    /**
-   * @dev implement supportsInterface(bytes4) using a lookup table
+     * @dev private method for registering an interface
-   */
+     */
-  function supportsInterface(bytes4 interfaceId)
+    function _registerInterface(bytes4 interfaceId) internal {
-    external
+        require(interfaceId != 0xffffffff);
-    view
+        _supportedInterfaces[interfaceId] = true;
-    returns (bool)
+    }
-  {
-    return _supportedInterfaces[interfaceId];
-  }
-
-  /**
-   * @dev private method for registering an interface
-   */
-  function _registerInterface(bytes4 interfaceId)
-    internal
-  {
-    require(interfaceId != 0xffffffff);
-    _supportedInterfaces[interfaceId] = true;
-  }
 }
 
 contract ERC165InterfacesSupported is SupportsInterfaceWithLookupMock {
-  constructor (bytes4[] interfaceIds)
+    constructor (bytes4[] memory interfaceIds) public {
-    public
+        for (uint256 i = 0; i < interfaceIds.length; i++) {
-  {
+            _registerInterface(interfaceIds[i]);
-    for (uint256 i = 0; i < interfaceIds.length; i++) {
+        }
-      _registerInterface(interfaceIds[i]);
     }
-  }
 }

contracts/mocks/ERC165/ERC165NotSupported.sol

@@ -1,5 +1,5 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 contract ERC165NotSupported {
-
+    // solhint-disable-previous-line no-empty-blocks
 }

contracts/mocks/ERC165CheckerMock.sol

@@ -1,31 +1,19 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../introspection/ERC165Checker.sol";
 
 contract ERC165CheckerMock {
-  using ERC165Checker for address;
+    using ERC165Checker for address;
 
-  function supportsERC165(address account)
+    function supportsERC165(address account) public view returns (bool) {
-    public
+        return account._supportsERC165();
-    view
+    }
-    returns (bool)
-  {
-    return account._supportsERC165();
-  }
 
-  function supportsInterface(address account, bytes4 interfaceId)
+    function supportsInterface(address account, bytes4 interfaceId) public view returns (bool) {
-    public
+        return account._supportsInterface(interfaceId);
-    view
+    }
-    returns (bool)
-  {
-    return account._supportsInterface(interfaceId);
-  }
 
-  function supportsAllInterfaces(address account, bytes4[] interfaceIds)
+    function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) public view returns (bool) {
-    public
+        return account._supportsAllInterfaces(interfaceIds);
-    view
+    }
-    returns (bool)
-  {
-    return account._supportsAllInterfaces(interfaceIds);
-  }
 }

contracts/mocks/ERC165Mock.sol

@@ -1,11 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../introspection/ERC165.sol";
 
 contract ERC165Mock is ERC165 {
-  function registerInterface(bytes4 interfaceId)
+    function registerInterface(bytes4 interfaceId) public {
-    public
+        _registerInterface(interfaceId);
-  {
+    }
-    _registerInterface(interfaceId);
-  }
 }

contracts/mocks/ERC20BurnableMock.sol

@@ -1,11 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20Burnable.sol";
 
 contract ERC20BurnableMock is ERC20Burnable {
-
+    constructor (address initialAccount, uint256 initialBalance) public {
-  constructor(address initialAccount, uint256 initialBalance) public {
+        _mint(initialAccount, initialBalance);
-    _mint(initialAccount, initialBalance);
+    }
-  }
-
 }

contracts/mocks/ERC20MintableMock.sol

@@ -1,7 +1,8 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20Mintable.sol";
 import "./MinterRoleMock.sol";
 
 contract ERC20MintableMock is ERC20Mintable, MinterRoleMock {
+    // solhint-disable-previous-line no-empty-blocks
 }

contracts/mocks/ERC20Mock.sol

@@ -1,24 +1,22 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20.sol";
 
 // mock class using ERC20
 contract ERC20Mock is ERC20 {
+    constructor (address initialAccount, uint256 initialBalance) public {
+        _mint(initialAccount, initialBalance);
+    }
 
-  constructor(address initialAccount, uint256 initialBalance) public {
+    function mint(address account, uint256 amount) public {
-    _mint(initialAccount, initialBalance);
+        _mint(account, amount);
-  }
+    }
 
-  function mint(address account, uint256 amount) public {
+    function burn(address account, uint256 amount) public {
-    _mint(account, amount);
+        _burn(account, amount);
-  }
+    }
-
-  function burn(address account, uint256 amount) public {
-    _burn(account, amount);
-  }
-
-  function burnFrom(address account, uint256 amount) public {
-    _burnFrom(account, amount);
-  }
 
+    function burnFrom(address account, uint256 amount) public {
+        _burnFrom(account, amount);
+    }
 }

contracts/mocks/ERC20PausableMock.sol

@@ -1,13 +1,11 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20Pausable.sol";
 import "./PauserRoleMock.sol";
 
 // mock class using ERC20Pausable
 contract ERC20PausableMock is ERC20Pausable, PauserRoleMock {
-
+    constructor (address initialAccount, uint initialBalance) public {
-  constructor(address initialAccount, uint initialBalance) public {
+        _mint(initialAccount, initialBalance);
-    _mint(initialAccount, initialBalance);
+    }
-  }
-
 }

contracts/mocks/ERC20WithMetadataMock.sol

@@ -1,11 +1,10 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20.sol";
 import "../drafts/ERC1046/TokenMetadata.sol";
 
 contract ERC20WithMetadataMock is ERC20, ERC20WithMetadata {
-  constructor(string tokenURI) public
+    constructor (string memory tokenURI) public ERC20WithMetadata(tokenURI) {
-    ERC20WithMetadata(tokenURI)
+        // solhint-disable-previous-line no-empty-blocks
-  {
+    }
-  }
 }

contracts/mocks/ERC721FullMock.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC721/ERC721Full.sol";
 import "../token/ERC721/ERC721Mintable.sol";
@@ -7,26 +7,23 @@ import "../token/ERC721/ERC721Burnable.sol";
 
 /**
  * @title ERC721FullMock
- * This mock just provides a public mint and burn functions for testing purposes,
+ * This mock just provides public functions for setting metadata URI, getting all tokens of an owner,
- * and a public setter for metadata URI
+ * checking token existence, removal of a token from an address
  */
-contract ERC721FullMock
+contract ERC721FullMock is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
-  is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
+    constructor (string memory name, string memory symbol) public ERC721Mintable() ERC721Full(name, symbol) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  constructor(string name, string symbol) public
+    function exists(uint256 tokenId) public view returns (bool) {
-    ERC721Mintable()
+        return _exists(tokenId);
-    ERC721Full(name, symbol)
+    }
-  {}
 
-  function exists(uint256 tokenId) public view returns (bool) {
+    function tokensOfOwner(address owner) public view returns (uint256[] memory) {
-    return _exists(tokenId);
+        return _tokensOfOwner(owner);
-  }
+    }
 
-  function setTokenURI(uint256 tokenId, string uri) public {
+    function setTokenURI(uint256 tokenId, string memory uri) public {
-    _setTokenURI(tokenId, uri);
+        _setTokenURI(tokenId, uri);
-  }
+    }
-
-  function removeTokenFrom(address from, uint256 tokenId) public {
-    _removeTokenFrom(from, tokenId);
-  }
 }

contracts/mocks/ERC721MintableBurnableImpl.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC721/ERC721Full.sol";
 import "../token/ERC721/ERC721Mintable.sol";
@@ -8,13 +8,8 @@ import "../token/ERC721/ERC721Burnable.sol";
 /**
  * @title ERC721MintableBurnableImpl
  */
-contract ERC721MintableBurnableImpl
+contract ERC721MintableBurnableImpl is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
-  is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
+    constructor () public ERC721Mintable() ERC721Full("Test", "TEST") {
-
+        // solhint-disable-previous-line no-empty-blocks
-  constructor()
+    }
-    ERC721Mintable()
-    ERC721Full("Test", "TEST")
-    public
-  {
-  }
 }

contracts/mocks/ERC721Mock.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC721/ERC721.sol";
 
@@ -7,11 +7,15 @@ import "../token/ERC721/ERC721.sol";
  * This mock just provides a public mint and burn functions for testing purposes
  */
 contract ERC721Mock is ERC721 {
-  function mint(address to, uint256 tokenId) public {
+    function mint(address to, uint256 tokenId) public {
-    _mint(to, tokenId);
+        _mint(to, tokenId);
-  }
+    }
 
-  function burn(uint256 tokenId) public {
+    function burn(address owner, uint256 tokenId) public {
-    _burn(ownerOf(tokenId), tokenId);
+        _burn(owner, tokenId);
-  }
+    }
+
+    function burn(uint256 tokenId) public {
+        _burn(tokenId);
+    }
 }

contracts/mocks/ERC721PausableMock.sol

@@ -1,4 +1,4 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC721/ERC721Pausable.sol";
 import "./PauserRoleMock.sol";
@@ -8,15 +8,15 @@ import "./PauserRoleMock.sol";
  * This mock just provides a public mint, burn and exists functions for testing purposes
  */
 contract ERC721PausableMock is ERC721Pausable, PauserRoleMock {
-  function mint(address to, uint256 tokenId) public {
+    function mint(address to, uint256 tokenId) public {
-    super._mint(to, tokenId);
+        super._mint(to, tokenId);
-  }
+    }
 
-  function burn(uint256 tokenId) public {
+    function burn(uint256 tokenId) public {
-    super._burn(ownerOf(tokenId), tokenId);
+        super._burn(tokenId);
-  }
+    }
 
-  function exists(uint256 tokenId) public view returns (bool) {
+    function exists(uint256 tokenId) public view returns (bool) {
-    return super._exists(tokenId);
+        return super._exists(tokenId);
-  }
+    }
 }

contracts/mocks/ERC721ReceiverMock.sol

@@ -1,41 +1,23 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC721/IERC721Receiver.sol";
 
 contract ERC721ReceiverMock is IERC721Receiver {
-  bytes4 private _retval;
+    bytes4 private _retval;
-  bool private _reverts;
+    bool private _reverts;
 
-  event Received(
+    event Received(address operator, address from, uint256 tokenId, bytes data, uint256 gas);
-    address operator,
-    address from,
-    uint256 tokenId,
-    bytes data,
-    uint256 gas
-  );
 
-  constructor(bytes4 retval, bool reverts) public {
+    constructor (bytes4 retval, bool reverts) public {
-    _retval = retval;
+        _retval = retval;
-    _reverts = reverts;
+        _reverts = reverts;
-  }
+    }
 
-  function onERC721Received(
+    function onERC721Received(address operator, address from, uint256 tokenId, bytes memory data)
-    address operator,
+        public returns (bytes4)
-    address from,
+    {
-    uint256 tokenId,
+        require(!_reverts);
-    bytes data
+        emit Received(operator, from, tokenId, data, gasleft());
-  )
+        return _retval;
-    public
+    }
-    returns(bytes4)
-  {
-    require(!_reverts);
-    emit Received(
-      operator,
-      from,
-      tokenId,
-      data,
-      gasleft() // msg.gas was deprecated in solidityv0.4.21
-    );
-    return _retval;
-  }
 }

contracts/mocks/EventEmitter.sol

@@ -1,62 +1,73 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 contract EventEmitter {
-  event Argumentless();
+    event Argumentless();
-  event ShortUint(uint8 value);
+    event ShortUint(uint8 value);
-  event ShortInt(int8 value);
+    event ShortInt(int8 value);
-  event LongUint(uint256 value);
+    event LongUint(uint256 value);
-  event LongInt(int256 value);
+    event LongInt(int256 value);
-  event Address(address value);
+    event Address(address value);
-  event Boolean(bool value);
+    event Boolean(bool value);
-  event String(string value);
+    event String(string value);
-  event LongUintBooleanString(
+    event LongUintBooleanString(uint256 uintValue, bool booleanValue, string stringValue);
-    uint256 uintValue,
-    bool booleanValue,
-    string stringValue
-  );
 
-  function emitArgumentless() public {
+    constructor (uint8 uintValue, bool booleanValue, string memory stringValue) public {
-    emit Argumentless();
+        emit ShortUint(uintValue);
-  }
+        emit Boolean(booleanValue);
+        emit String(stringValue);
+    }
 
-  function emitShortUint(uint8 value) public {
+    function emitArgumentless() public {
-    emit ShortUint(value);
+        emit Argumentless();
-  }
+    }
 
-  function emitShortInt(int8 value) public {
+    function emitShortUint(uint8 value) public {
-    emit ShortInt(value);
+        emit ShortUint(value);
-  }
+    }
 
-  function emitLongUint(uint256 value) public {
+    function emitShortInt(int8 value) public {
-    emit LongUint(value);
+        emit ShortInt(value);
-  }
+    }
 
-  function emitLongInt(int256 value) public {
+    function emitLongUint(uint256 value) public {
-    emit LongInt(value);
+        emit LongUint(value);
-  }
+    }
 
-  function emitAddress(address value) public {
+    function emitLongInt(int256 value) public {
-    emit Address(value);
+        emit LongInt(value);
-  }
+    }
 
-  function emitBoolean(bool value) public {
+    function emitAddress(address value) public {
-    emit Boolean(value);
+        emit Address(value);
-  }
+    }
 
-  function emitString(string value) public {
+    function emitBoolean(bool value) public {
-    emit String(value);
+        emit Boolean(value);
-  }
+    }
 
-  function emitLongUintBooleanString(
+    function emitString(string memory value) public {
-    uint256 uintValue,
+        emit String(value);
-    bool booleanValue,
+    }
-    string stringValue)
-  public {
-    emit LongUintBooleanString(uintValue, booleanValue, stringValue);
-  }
 
-  function emitLongUintAndBoolean(uint256 uintValue, bool boolValue) public {
+    function emitLongUintBooleanString(uint256 uintValue, bool booleanValue, string memory stringValue) public {
-    emit LongUint(uintValue);
+        emit LongUintBooleanString(uintValue, booleanValue, stringValue);
-    emit Boolean(boolValue);
+    }
-  }
+
+    function emitLongUintAndBoolean(uint256 uintValue, bool boolValue) public {
+        emit LongUint(uintValue);
+        emit Boolean(boolValue);
+    }
+
+    function emitStringAndEmitIndirectly(string memory value, IndirectEventEmitter emitter) public {
+        emit String(value);
+        emitter.emitStringIndirectly(value);
+    }
+}
+
+contract IndirectEventEmitter {
+    event IndirectString(string value);
+
+    function emitStringIndirectly(string memory value) public {
+        emit IndirectString(value);
+    }
 }

contracts/mocks/Failer.sol

@@ -0,0 +1,23 @@
+pragma solidity ^0.5.0;
+
+contract Failer {
+    uint256[] private array;
+
+    function dontFail() public pure {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    function failWithRevert() public pure {
+        revert();
+    }
+
+    function failWithThrow() public pure {
+        assert(false);
+    }
+
+    function failWithOutOfGas() public {
+        for (uint256 i = 0; i < 2**200; ++i) {
+            array.push(i);
+        }
+    }
+}

contracts/mocks/FinalizableCrowdsaleImpl.sol

@@ -1,21 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../crowdsale/distribution/FinalizableCrowdsale.sol";
 
 contract FinalizableCrowdsaleImpl is FinalizableCrowdsale {
-
+    constructor (uint256 openingTime, uint256 closingTime, uint256 rate, address payable wallet, IERC20 token)
-  constructor (
+        public
-    uint256 openingTime,
+        Crowdsale(rate, wallet, token)
-    uint256 closingTime,
+        TimedCrowdsale(openingTime, closingTime)
-    uint256 rate,
+    {
-    address wallet,
+        // solhint-disable-previous-line no-empty-blocks
-    IERC20 token
+    }
-  )
-    public
-    Crowdsale(rate, wallet, token)
-    TimedCrowdsale(openingTime, closingTime)
-  {
-  }
-
 }

contracts/mocks/IncreasingPriceCrowdsaleImpl.sol

@@ -1,23 +1,22 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../crowdsale/price/IncreasingPriceCrowdsale.sol";
 import "../math/SafeMath.sol";
 
 contract IncreasingPriceCrowdsaleImpl is IncreasingPriceCrowdsale {
-
+    constructor (
-  constructor (
+        uint256 openingTime,
-    uint256 openingTime,
+        uint256 closingTime,
-    uint256 closingTime,
+        address payable wallet,
-    address wallet,
+        IERC20 token,
-    IERC20 token,
+        uint256 initialRate,
-    uint256 initialRate,
+        uint256 finalRate
-    uint256 finalRate
+    )
-  )
+        public
-    public
+        Crowdsale(initialRate, wallet, token)
-    Crowdsale(initialRate, wallet, token)
+        TimedCrowdsale(openingTime, closingTime)
-    TimedCrowdsale(openingTime, closingTime)
+        IncreasingPriceCrowdsale(initialRate, finalRate)
-    IncreasingPriceCrowdsale(initialRate, finalRate)
+    {
-  {
+        // solhint-disable-previous-line no-empty-blocks
-  }
+    }
-
 }

contracts/mocks/IndividuallyCappedCrowdsaleImpl.sol

@@ -1,19 +1,11 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../crowdsale/validation/IndividuallyCappedCrowdsale.sol";
 import "./CapperRoleMock.sol";
 
-contract IndividuallyCappedCrowdsaleImpl
+contract IndividuallyCappedCrowdsaleImpl is IndividuallyCappedCrowdsale, CapperRoleMock {
-  is IndividuallyCappedCrowdsale, CapperRoleMock {
+    constructor (uint256 rate, address payable wallet, IERC20 token) public Crowdsale(rate, wallet, token) {
-
+        // solhint-disable-previous-line no-empty-blocks
-  constructor(
+    }
-    uint256 rate,
-    address wallet,
-    IERC20 token
-  )
-    public
-    Crowdsale(rate, wallet, token)
-  {
-  }
 }

contracts/mocks/MathMock.sol

@@ -1,17 +1,17 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../math/Math.sol";
 
 contract MathMock {
-  function max(uint256 a, uint256 b) public pure returns (uint256) {
+    function max(uint256 a, uint256 b) public pure returns (uint256) {
-    return Math.max(a, b);
+        return Math.max(a, b);
-  }
+    }
 
-  function min(uint256 a, uint256 b) public pure returns (uint256) {
+    function min(uint256 a, uint256 b) public pure returns (uint256) {
-    return Math.min(a, b);
+        return Math.min(a, b);
-  }
+    }
 
-  function average(uint256 a, uint256 b) public pure returns (uint256) {
+    function average(uint256 a, uint256 b) public pure returns (uint256) {
-    return Math.average(a, b);
+        return Math.average(a, b);
-  }
+    }
 }

contracts/mocks/MerkleProofWrapper.sol

@@ -1,18 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import { MerkleProof } from "../cryptography/MerkleProof.sol";
 
 contract MerkleProofWrapper {
-
+    function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) public pure returns (bool) {
-  function verify(
+        return MerkleProof.verify(proof, root, leaf);
-    bytes32[] proof,
+    }
-    bytes32 root,
-    bytes32 leaf
-  )
-    public
-    pure
-    returns (bool)
-  {
-    return MerkleProof.verify(proof, root, leaf);
-  }
 }

contracts/mocks/MintedCrowdsaleImpl.sol

@@ -1,18 +1,10 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/ERC20Mintable.sol";
 import "../crowdsale/emission/MintedCrowdsale.sol";
 
 contract MintedCrowdsaleImpl is MintedCrowdsale {
-
+    constructor (uint256 rate, address payable wallet, ERC20Mintable token) public Crowdsale(rate, wallet, token) {
-  constructor (
+        // solhint-disable-previous-line no-empty-blocks
-    uint256 rate,
+    }
-    address wallet,
-    ERC20Mintable token
-  )
-    public
-    Crowdsale(rate, wallet, token)
-  {
-  }
-
 }

contracts/mocks/MinterRoleMock.sol

@@ -1,17 +1,18 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/roles/MinterRole.sol";
 
 contract MinterRoleMock is MinterRole {
-  function removeMinter(address account) public {
+    function removeMinter(address account) public {
-    _removeMinter(account);
+        _removeMinter(account);
-  }
+    }
 
-  function onlyMinterMock() public view onlyMinter {
+    function onlyMinterMock() public view onlyMinter {
-  }
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  // Causes a compilation error if super._removeMinter is not internal
+    // Causes a compilation error if super._removeMinter is not internal
-  function _removeMinter(address account) internal {
+    function _removeMinter(address account) internal {
-    super._removeMinter(account);
+        super._removeMinter(account);
-  }
+    }
 }

contracts/mocks/OwnableInterfaceId.sol

@@ -0,0 +1,15 @@
+pragma solidity ^0.5.0;
+
+import "../ownership/Ownable.sol";
+
+/**
+ * @title Ownable interface id calculator.
+ * @dev See the EIP165 specification for more information:
+ * https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md#specification
+ */
+contract OwnableInterfaceId {
+    function getInterfaceId() public pure returns (bytes4) {
+        Ownable i;
+        return i.owner.selector ^ i.isOwner.selector ^ i.renounceOwnership.selector ^ i.transferOwnership.selector;
+    }
+}

contracts/mocks/OwnableMock.sol

@@ -1,6 +1,7 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../ownership/Ownable.sol";
 
 contract OwnableMock is Ownable {
+    // solhint-disable-previous-line no-empty-blocks
 }

contracts/mocks/PausableCrowdsaleImpl.sol

@@ -0,0 +1,10 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC20/ERC20.sol";
+import "../crowdsale/validation/PausableCrowdsale.sol";
+
+contract PausableCrowdsaleImpl is PausableCrowdsale {
+    constructor (uint256 _rate, address payable _wallet, ERC20 _token) public Crowdsale(_rate, _wallet, _token) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+}

contracts/mocks/PausableMock.sol

@@ -1,24 +1,23 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../lifecycle/Pausable.sol";
 import "./PauserRoleMock.sol";
 
 // mock class using Pausable
 contract PausableMock is Pausable, PauserRoleMock {
-  bool public drasticMeasureTaken;
+    bool public drasticMeasureTaken;
-  uint256 public count;
+    uint256 public count;
 
-  constructor() public {
+    constructor () public {
-    drasticMeasureTaken = false;
+        drasticMeasureTaken = false;
-    count = 0;
+        count = 0;
-  }
+    }
 
-  function normalProcess() external whenNotPaused {
+    function normalProcess() external whenNotPaused {
-    count++;
+        count++;
-  }
+    }
-
-  function drasticMeasure() external whenPaused {
-    drasticMeasureTaken = true;
-  }
 
+    function drasticMeasure() external whenPaused {
+        drasticMeasureTaken = true;
+    }
 }

contracts/mocks/PauserRoleMock.sol

@@ -1,17 +1,18 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/roles/PauserRole.sol";
 
 contract PauserRoleMock is PauserRole {
-  function removePauser(address account) public {
+    function removePauser(address account) public {
-    _removePauser(account);
+        _removePauser(account);
-  }
+    }
 
-  function onlyPauserMock() public view onlyPauser {
+    function onlyPauserMock() public view onlyPauser {
-  }
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  // Causes a compilation error if super._removePauser is not internal
+    // Causes a compilation error if super._removePauser is not internal
-  function _removePauser(address account) internal {
+    function _removePauser(address account) internal {
-    super._removePauser(account);
+        super._removePauser(account);
-  }
+    }
 }

contracts/mocks/PostDeliveryCrowdsaleImpl.sol

@@ -1,21 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../crowdsale/distribution/PostDeliveryCrowdsale.sol";
 
 contract PostDeliveryCrowdsaleImpl is PostDeliveryCrowdsale {
-
+    constructor (uint256 openingTime, uint256 closingTime, uint256 rate, address payable wallet, IERC20 token)
-  constructor (
+        public
-    uint256 openingTime,
+        TimedCrowdsale(openingTime, closingTime)
-    uint256 closingTime,
+        Crowdsale(rate, wallet, token)
-    uint256 rate,
+    {
-    address wallet,
+        // solhint-disable-previous-line no-empty-blocks
-    IERC20 token
+    }
-  )
-    public
-    TimedCrowdsale(openingTime, closingTime)
-    Crowdsale(rate, wallet, token)
-  {
-  }
-
 }

contracts/mocks/PullPaymentMock.sol

@@ -1,15 +1,15 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../payment/PullPayment.sol";
 
 // mock class using PullPayment
 contract PullPaymentMock is PullPayment {
+    constructor () public payable {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  constructor() public payable { }
+    // test helper function to call asyncTransfer
-
+    function callTransfer(address dest, uint256 amount) public {
-  // test helper function to call asyncTransfer
+        _asyncTransfer(dest, amount);
-  function callTransfer(address dest, uint256 amount) public {
+    }
-    _asyncTransfer(dest, amount);
-  }
-
 }

contracts/mocks/ReentrancyAttack.sol

@@ -1,10 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 contract ReentrancyAttack {
-
+    function callSender(bytes4 data) public {
-  function callSender(bytes4 data) public {
+        // solhint-disable-next-line avoid-low-level-calls
-    // solium-disable-next-line security/no-low-level-calls
+        (bool success,) = msg.sender.call(abi.encodeWithSelector(data));
-    require(msg.sender.call(abi.encodeWithSelector(data)));
+        require(success);
-  }
+    }
-
 }

contracts/mocks/ReentrancyMock.sol

@@ -1,44 +1,42 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../utils/ReentrancyGuard.sol";
 import "./ReentrancyAttack.sol";
 
 contract ReentrancyMock is ReentrancyGuard {
+    uint256 public counter;
 
-  uint256 public counter;
+    constructor () public {
-
+        counter = 0;
-  constructor() public {
-    counter = 0;
-  }
-
-  function callback() external nonReentrant {
-    count();
-  }
-
-  function countLocalRecursive(uint256 n) public nonReentrant {
-    if (n > 0) {
-      count();
-      countLocalRecursive(n - 1);
     }
-  }
 
-  function countThisRecursive(uint256 n) public nonReentrant {
+    function callback() external nonReentrant {
-    if (n > 0) {
+        count();
-      count();
-      // solium-disable-next-line security/no-low-level-calls
-      bool result = address(this).call(abi.encodeWithSignature("countThisRecursive(uint256)", n - 1));
-      require(result == true);
     }
-  }
 
-  function countAndCall(ReentrancyAttack attacker) public nonReentrant {
+    function countLocalRecursive(uint256 n) public nonReentrant {
-    count();
+        if (n > 0) {
-    bytes4 func = bytes4(keccak256("callback()"));
+            count();
-    attacker.callSender(func);
+            countLocalRecursive(n - 1);
-  }
+        }
+    }
 
-  function count() private {
+    function countThisRecursive(uint256 n) public nonReentrant {
-    counter += 1;
+        if (n > 0) {
-  }
+            count();
+            // solhint-disable-next-line avoid-low-level-calls
+            (bool success,) = address(this).call(abi.encodeWithSignature("countThisRecursive(uint256)", n - 1));
+            require(success);
+        }
+    }
 
+    function countAndCall(ReentrancyAttack attacker) public nonReentrant {
+        count();
+        bytes4 func = bytes4(keccak256("callback()"));
+        attacker.callSender(func);
+    }
+
+    function count() private {
+        counter += 1;
+    }
 }

contracts/mocks/RefundableCrowdsaleImpl.sol

@@ -1,23 +1,22 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/ERC20Mintable.sol";
+import "../token/ERC20/IERC20.sol";
 import "../crowdsale/distribution/RefundableCrowdsale.sol";
 
 contract RefundableCrowdsaleImpl is RefundableCrowdsale {
-
+    constructor (
-  constructor (
+        uint256 openingTime,
-    uint256 openingTime,
+        uint256 closingTime,
-    uint256 closingTime,
+        uint256 rate,
-    uint256 rate,
+        address payable wallet,
-    address wallet,
+        IERC20 token,
-    ERC20Mintable token,
+        uint256 goal
-    uint256 goal
+    )
-  )
+        public
-    public
+        Crowdsale(rate, wallet, token)
-    Crowdsale(rate, wallet, token)
+        TimedCrowdsale(openingTime, closingTime)
-    TimedCrowdsale(openingTime, closingTime)
+        RefundableCrowdsale(goal)
-    RefundableCrowdsale(goal)
+    {
-  {
+        // solhint-disable-previous-line no-empty-blocks
-  }
+    }
-
 }

contracts/mocks/RefundablePostDeliveryCrowdsaleImpl.sol

@@ -0,0 +1,22 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC20/IERC20.sol";
+import "../crowdsale/distribution/RefundablePostDeliveryCrowdsale.sol";
+
+contract RefundablePostDeliveryCrowdsaleImpl is RefundablePostDeliveryCrowdsale {
+    constructor (
+        uint256 openingTime,
+        uint256 closingTime,
+        uint256 rate,
+        address payable wallet,
+        IERC20 token,
+        uint256 goal
+    )
+        public
+        Crowdsale(rate, wallet, token)
+        TimedCrowdsale(openingTime, closingTime)
+        RefundableCrowdsale(goal)
+    {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+}

contracts/mocks/RolesMock.sol

@@ -1,21 +1,21 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../access/Roles.sol";
 
 contract RolesMock {
-  using Roles for Roles.Role;
+    using Roles for Roles.Role;
 
-  Roles.Role private dummyRole;
+    Roles.Role private dummyRole;
 
-  function add(address account) public {
+    function add(address account) public {
-    dummyRole.add(account);
+        dummyRole.add(account);
-  }
+    }
 
-  function remove(address account) public {
+    function remove(address account) public {
-    dummyRole.remove(account);
+        dummyRole.remove(account);
-  }
+    }
 
-  function has(address account) public view returns (bool) {
+    function has(address account) public view returns (bool) {
-    return dummyRole.has(account);
+        return dummyRole.has(account);
-  }
+    }
 }

contracts/mocks/SafeERC20Helper.sol

@@ -1,112 +1,108 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../token/ERC20/IERC20.sol";
 import "../token/ERC20/SafeERC20.sol";
 
 contract ERC20FailingMock {
-  uint256 private _allowance;
+    uint256 private _allowance;
 
-  function transfer(address, uint256) public returns (bool) {
+    function transfer(address, uint256) public returns (bool) {
-    return false;
+        return false;
-  }
+    }
 
-  function transferFrom(address, address, uint256) public returns (bool) {
+    function transferFrom(address, address, uint256) public returns (bool) {
-    return false;
+        return false;
-  }
+    }
 
-  function approve(address, uint256) public returns (bool) {
+    function approve(address, uint256) public returns (bool) {
-    return false;
+        return false;
-  }
+    }
 
-  function allowance(address, address) public view returns (uint256) {
+    function allowance(address, address) public view returns (uint256) {
-    return 0;
+        return 0;
-  }
+    }
 }
 
 contract ERC20SucceedingMock {
-  mapping (address => uint256) private _allowances;
+    mapping (address => uint256) private _allowances;
 
-  function transfer(address, uint256) public returns (bool) {
+    function transfer(address, uint256) public returns (bool) {
-    return true;
+        return true;
-  }
+    }
 
-  function transferFrom(address, address, uint256) public returns (bool) {
+    function transferFrom(address, address, uint256) public returns (bool) {
-    return true;
+        return true;
-  }
+    }
 
-  function approve(address, uint256) public returns (bool) {
+    function approve(address, uint256) public returns (bool) {
-    return true;
+        return true;
-  }
+    }
 
-  function setAllowance(uint256 allowance_) public {
+    function setAllowance(uint256 allowance_) public {
-    _allowances[msg.sender] = allowance_;
+        _allowances[msg.sender] = allowance_;
-  }
+    }
 
-  function allowance(address owner, address) public view returns (uint256) {
+    function allowance(address owner, address) public view returns (uint256) {
-    return _allowances[owner];
+        return _allowances[owner];
-  }
+    }
 }
 
 contract SafeERC20Helper {
-  using SafeERC20 for IERC20;
+    using SafeERC20 for IERC20;
 
-  IERC20 private _failing;
+    IERC20 private _failing;
-  IERC20 private _succeeding;
+    IERC20 private _succeeding;
 
-  constructor() public {
+    constructor () public {
-    _failing = IERC20(new ERC20FailingMock());
+        _failing = IERC20(address(new ERC20FailingMock()));
-    _succeeding = IERC20(new ERC20SucceedingMock());
+        _succeeding = IERC20(address(new ERC20SucceedingMock()));
-  }
+    }
 
-  // Using _failing
+    function doFailingTransfer() public {
+        _failing.safeTransfer(address(0), 0);
+    }
 
-  function doFailingTransfer() public {
+    function doFailingTransferFrom() public {
-    _failing.safeTransfer(address(0), 0);
+        _failing.safeTransferFrom(address(0), address(0), 0);
-  }
+    }
 
-  function doFailingTransferFrom() public {
+    function doFailingApprove() public {
-    _failing.safeTransferFrom(address(0), address(0), 0);
+        _failing.safeApprove(address(0), 0);
-  }
+    }
 
-  function doFailingApprove() public {
+    function doFailingIncreaseAllowance() public {
-    _failing.safeApprove(address(0), 0);
+        _failing.safeIncreaseAllowance(address(0), 0);
-  }
+    }
 
-  function doFailingIncreaseAllowance() public {
+    function doFailingDecreaseAllowance() public {
-    _failing.safeIncreaseAllowance(address(0), 0);
+        _failing.safeDecreaseAllowance(address(0), 0);
-  }
+    }
 
-  function doFailingDecreaseAllowance() public {
+    function doSucceedingTransfer() public {
-    _failing.safeDecreaseAllowance(address(0), 0);
+        _succeeding.safeTransfer(address(0), 0);
-  }
+    }
 
-  // Using _succeeding
+    function doSucceedingTransferFrom() public {
+        _succeeding.safeTransferFrom(address(0), address(0), 0);
+    }
 
-  function doSucceedingTransfer() public {
+    function doSucceedingApprove(uint256 amount) public {
-    _succeeding.safeTransfer(address(0), 0);
+        _succeeding.safeApprove(address(0), amount);
-  }
+    }
 
-  function doSucceedingTransferFrom() public {
+    function doSucceedingIncreaseAllowance(uint256 amount) public {
-    _succeeding.safeTransferFrom(address(0), address(0), 0);
+        _succeeding.safeIncreaseAllowance(address(0), amount);
-  }
+    }
 
-  function doSucceedingApprove(uint256 amount) public {
+    function doSucceedingDecreaseAllowance(uint256 amount) public {
-    _succeeding.safeApprove(address(0), amount);
+        _succeeding.safeDecreaseAllowance(address(0), amount);
-  }
+    }
 
-  function doSucceedingIncreaseAllowance(uint256 amount) public {
+    function setAllowance(uint256 allowance_) public {
-    _succeeding.safeIncreaseAllowance(address(0), amount);
+        ERC20SucceedingMock(address(_succeeding)).setAllowance(allowance_);
-  }
+    }
 
-  function doSucceedingDecreaseAllowance(uint256 amount) public {
+    function allowance() public view returns (uint256) {
-    _succeeding.safeDecreaseAllowance(address(0), amount);
+        return _succeeding.allowance(address(0), address(0));
-  }
+    }
-
-  function setAllowance(uint256 allowance_) public {
-    ERC20SucceedingMock(_succeeding).setAllowance(allowance_);
-  }
-
-  function allowance() public view returns (uint256) {
-    return _succeeding.allowance(address(0), address(0));
-  }
 }

contracts/mocks/SafeMathMock.sol

@@ -1,26 +1,25 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../math/SafeMath.sol";
 
 contract SafeMathMock {
+    function mul(uint256 a, uint256 b) public pure returns (uint256) {
+        return SafeMath.mul(a, b);
+    }
 
-  function mul(uint256 a, uint256 b) public pure returns (uint256) {
+    function div(uint256 a, uint256 b) public pure returns (uint256) {
-    return SafeMath.mul(a, b);
+        return SafeMath.div(a, b);
-  }
+    }
 
-  function div(uint256 a, uint256 b) public pure returns (uint256) {
+    function sub(uint256 a, uint256 b) public pure returns (uint256) {
-    return SafeMath.div(a, b);
+        return SafeMath.sub(a, b);
-  }
+    }
 
-  function sub(uint256 a, uint256 b) public pure returns (uint256) {
+    function add(uint256 a, uint256 b) public pure returns (uint256) {
-    return SafeMath.sub(a, b);
+        return SafeMath.add(a, b);
-  }
+    }
 
-  function add(uint256 a, uint256 b) public pure returns (uint256) {
+    function mod(uint256 a, uint256 b) public pure returns (uint256) {
-    return SafeMath.add(a, b);
+        return SafeMath.mod(a, b);
-  }
+    }
-
-  function mod(uint256 a, uint256 b) public pure returns (uint256) {
-    return SafeMath.mod(a, b);
-  }
 }

contracts/mocks/SecondaryMock.sol

@@ -1,8 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../ownership/Secondary.sol";
 
 contract SecondaryMock is Secondary {
-  function onlyPrimaryMock() public view onlyPrimary {
+    function onlyPrimaryMock() public view onlyPrimary {
-  }
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/mocks/SignatureBouncerMock.sol

@@ -1,73 +1,50 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../drafts/SignatureBouncer.sol";
 import "./SignerRoleMock.sol";
 
 contract SignatureBouncerMock is SignatureBouncer, SignerRoleMock {
-  function checkValidSignature(address account, bytes signature)
+    function checkValidSignature(address account, bytes memory signature)
-    public
+        public view returns (bool)
-    view
+    {
-    returns (bool)
+        return _isValidSignature(account, signature);
-  {
+    }
-    return _isValidSignature(account, signature);
-  }
 
-  function onlyWithValidSignature(bytes signature)
+    function onlyWithValidSignature(bytes memory signature)
-    public
+        public onlyValidSignature(signature) view
-    onlyValidSignature(signature)
+    {
-    view
+        // solhint-disable-previous-line no-empty-blocks
-  {
+    }
 
-  }
+    function checkValidSignatureAndMethod(address account, bytes memory signature)
+        public view returns (bool)
+    {
+        return _isValidSignatureAndMethod(account, signature);
+    }
 
-  function checkValidSignatureAndMethod(address account, bytes signature)
+    function onlyWithValidSignatureAndMethod(bytes memory signature)
-    public
+        public onlyValidSignatureAndMethod(signature) view
-    view
+    {
-    returns (bool)
+        // solhint-disable-previous-line no-empty-blocks
-  {
+    }
-    return _isValidSignatureAndMethod(account, signature);
-  }
 
-  function onlyWithValidSignatureAndMethod(bytes signature)
+    function checkValidSignatureAndData(address account, bytes memory, uint, bytes memory signature)
-    public
+        public view returns (bool)
-    onlyValidSignatureAndMethod(signature)
+    {
-    view
+        return _isValidSignatureAndData(account, signature);
-  {
+    }
 
-  }
+    function onlyWithValidSignatureAndData(uint, bytes memory signature)
+        public onlyValidSignatureAndData(signature) view
+    {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  function checkValidSignatureAndData(
+    function theWrongMethod(bytes memory) public pure {
-    address account,
+        // solhint-disable-previous-line no-empty-blocks
-    bytes,
+    }
-    uint,
-    bytes signature
-  )
-    public
-    view
-    returns (bool)
-  {
-    return _isValidSignatureAndData(account, signature);
-  }
 
-  function onlyWithValidSignatureAndData(uint, bytes signature)
+    function tooShortMsgData() public onlyValidSignatureAndData("") view {
-    public
+        // solhint-disable-previous-line no-empty-blocks
-    onlyValidSignatureAndData(signature)
+    }
-    view
-  {
-
-  }
-
-  function theWrongMethod(bytes)
-    public
-    pure
-  {
-
-  }
-
-  function tooShortMsgData()
-    public
-    onlyValidSignatureAndData("")
-    view
-  {
-  }
 }

contracts/mocks/SignedSafeMathMock.sol

@@ -0,0 +1,21 @@
+pragma solidity ^0.5.0;
+
+import "../drafts/SignedSafeMath.sol";
+
+contract SignedSafeMathMock {
+    function mul(int256 a, int256 b) public pure returns (int256) {
+        return SignedSafeMath.mul(a, b);
+    }
+
+    function div(int256 a, int256 b) public pure returns (int256) {
+        return SignedSafeMath.div(a, b);
+    }
+
+    function sub(int256 a, int256 b) public pure returns (int256) {
+        return SignedSafeMath.sub(a, b);
+    }
+
+    function add(int256 a, int256 b) public pure returns (int256) {
+        return SignedSafeMath.add(a, b);
+    }
+}