Release v2.1.3

Fix SafeERC20.safeApprove bug

(cherry picked from commit 3111291b4a)

.babelrc

@@ -1,3 +0,0 @@
-{
-  "presets": ["es2015", "stage-2", "stage-3"]
-}

.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": {
 
@@ -25,13 +26,14 @@
 
     // Code style
     "camelcase": ["error", {"properties": "always"}],
-    "comma-dangle": ["warn", "always-multiline"],
+    "comma-dangle": ["error", "always-multiline"],
     "comma-spacing": ["error", {"before": false, "after": true}],
     "dot-notation": ["error", {"allowKeywords": true, "allowPattern": ""}],
     "eol-last": ["error", "always"],
     "eqeqeq": ["error", "smart"],
     "generator-star-spacing": ["error", "before"],
     "indent": ["error", 2],
+    "linebreak-style": ["error", "unix"],
     "max-len": ["error", 120, 2],
     "no-debugger": "off",
     "no-dupe-args": "error",
@@ -48,6 +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: -->
-
-- [ ] 📘 I've reviewed the [OpenZeppelin Contributor Guidelines](../blob/master/CONTRIBUTING.md)
-- [ ] ✅ I've added tests where applicable to test my new functionality.
-- [ ] 📖 I've made sure that my contracts are well-documented.
-- [ ] 🎨 I've run the JS/Solidity linters and fixed any issues (`npm run lint:all:fix`).
+<!-- 3. Before submitting, please make sure that you have:
+  - reviewed the OpenZeppelin Contributor Guidelines
+    (https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/CONTRIBUTING.md),
+  - added tests where applicable to test new functionality,
+  - made sure that your contracts are well-documented,
+  - 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

@@ -1,17 +0,0 @@
-{
-  "extends": "solium:all",
-  "plugins": ["security"],
-  "rules": {
-    "error-reason": "off",
-    "indentation": ["error", 2],
-    "max-len": ["warning", 79],
-    "no-constant": ["error"],
-    "no-empty-blocks": "off",
-    "quotes": ["error", "double"],
-    "uppercase": "off",
-
-    "security/enforce-explicit-visibility": ["error"],
-    "security/no-block-members": ["warning"],
-    "security/no-inline-assembly": ["warning"]
-  }
-}

.travis.yml

@@ -1,27 +1,50 @@
 dist: trusty
-sudo: required
+sudo: false
 group: beta
 language: node_js
 node_js:
   - "8"
+
 cache:
   directories:
     - node_modules
-env:
-  -
-  - SOLIDITY_COVERAGE=true
-  - SOLC_NIGHTLY=true
-matrix:
+
+jobs:
+  # XXX fast_finish doesn't work with stages yet. See
+  # https://github.com/travis-ci/travis-ci/issues/8425
+  # --elopio - 20180531
   fast_finish: true
   allow_failures:
-    - env: SOLIDITY_COVERAGE=true
     - env: SOLC_NIGHTLY=true
-before_script:
-  - truffle version
-script:
-  - npm run lint
-  - npm run lint:sol
-  - npm run test
+  include:
+    - stage: 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 using solc nightly"
+      script: npm run test
+      env: SOLC_NIGHTLY=true
+
+    - stage: update docs
+      if: tag =~ ^v[0-9]+\.[0-9]+\.[0-9]+$
+      addons:
+        apt:
+          packages:
+            - curl
+      script:
+        - ./scripts/ci/trigger_docs_update "${TRAVIS_TAG}"
+
 notifications:
   slack:
     rooms:

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))

CODE_STYLE.md

@@ -0,0 +1,63 @@
+# Code Style
+
+We value clean code and consistency, and those are prerequisites for us to
+include new code in the repository. Before proposing a change, please read this
+document and take some time to familiarize yourself with the style of the
+existing codebase.
+
+## Solidity code
+
+In order to be consistent with all the other Solidity projects, we follow the
+[official recommendations documented in the Solidity style guide](http://solidity.readthedocs.io/en/latest/style-guide.html).
+
+Any exception or additions specific to our project are documented below.
+
+### Naming
+
+* Try to avoid acronyms and abbreviations.
+
+* All state variables should be private.
+
+* Private state variables should have an underscore prefix.
+
+    ```
+    contract TestContract {
+      uint256 private _privateVar;
+      uint256 internal _internalVar;
+    }
+    ```
+
+* Parameters must not be prefixed with an underscore.
+
+    ```
+    function test(uint256 testParameter1, uint256 testParameter2) {
+    ...
+    }
+    ```
+
+* Internal and private functions should have an underscore prefix.
+
+    ```
+    function _testInternal() internal {
+      ...
+    }
+    ```
+
+    ```
+    function _testPrivate() private {
+      ...
+    }
+    ```
+
+* Events should be emitted immediately after the state change that they
+  represent, and consequently they should be named in past tense.
+
+    ```
+    function _burn(address _who, uint256 _value) internal {
+      super._burn(_who, _value);
+      emit TokensBurned(_who, _value);
+    }
+    ```
+
+  Some standards (e.g. ERC20) use present tense, and in those cases the
+  standard specification prevails.

README.md

@@ -1,131 +1,58 @@
-# OpenZeppelin Solidity
+# <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)
-[![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)
+[![Build Status](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity.svg?branch=master)](https://travis-ci.com/OpenZeppelin/openzeppelin-solidity)
+[![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 writing secure [Smart Contracts](https://en.wikipedia.org/wiki/Smart_contract) on Ethereum.
+**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.
 
-With OpenZeppelin, you can build distributed applications, protocols and organizations:
-- using common contract security patterns (See [Onward with Ethereum Smart Contract Security](https://medium.com/bitcorps-blog/onward-with-ethereum-smart-contract-security-97a827e47702#.y3kvdetbz))
-- in the [Solidity language](https://solidity.readthedocs.io/en/develop/).
+## Install
 
-> NOTE: New to smart contract development? Check our [introductory guide](https://medium.com/zeppelin-blog/the-hitchhikers-guide-to-smart-contracts-in-ethereum-848f08001f05#.cox40d2ut).
-
-## Getting Started
-
-OpenZeppelin integrates with [Truffle](https://github.com/ConsenSys/truffle) and [Embark](https://github.com/embark-framework/embark/).
-
-## truffle
-
-To use with Truffle, first install it and initialize your project with `truffle init`.
-
-```sh
-npm install -g truffle
-mkdir myproject && cd myproject
-truffle init
+```
+npm install openzeppelin-solidity
 ```
 
-## Embark
+## Usage
 
-To use with Embark, first install it and initialize your project with `embark new MyApp`.
-
-```sh
-npm install -g embark
-embark new MyApp
-cd MyApp
-```
-
-## Installing OpenZeppelin
-
-After installing either Framework, to install the OpenZeppelin library, run the following in your Solidity project root directory:
-
-```sh
-npm init -y
-npm install -E openzeppelin-solidity
-```
-
-**Note that OpenZeppelin does not currently follow semantic versioning.** You may encounter breaking changes upon a minor version bump. We recommend pinning the version of OpenZeppelin you use, as done by the `-E` (`--save-exact`) option.
-
-After that, you'll get all the library's contracts in the `node_modules/openzeppelin-solidity/contracts` folder. You can use the contracts in the library like so:
+To write your custom contracts, import ours and extend them through inheritance.
 
 ```solidity
-import 'openzeppelin-solidity/contracts/ownership/Ownable.sol';
+pragma solidity ^0.4.24;
 
-contract MyContract is Ownable {
-  ...
+import 'openzeppelin-solidity/contracts/token/ERC721/ERC721Full.sol';
+import 'openzeppelin-solidity/contracts/token/ERC721/ERC721Mintable.sol';
+
+contract MyNFT is ERC721Full, ERC721Mintable {
+  constructor() ERC721Full("MyNFT", "MNFT") public {
+  }
 }
 ```
 
-If you are using Embark, you can also import directly from github:
+> You need an ethereum development framework for the above import statements to work! Check out these guides for [Truffle] or [Embark].
 
-```solidity
-import "github.com/OpenZeppelin/openzeppelin-solidity/contracts/ownership/Ownable.sol#v1.9.0";
-
-contract MyContract is Ownable {
-  ...
-}
-```
-
-## Architecture
-The following provides visibility into how OpenZeppelin's contracts are organized:
-
-- **access** - Smart contracts that enable functionality that can be used for selective restrictions and basic authorization control functions. Includes address whitelisting and signature-based permissions management.
-	- **rbac** - A library used to manage addresses assigned to different user roles and an example Role-Based Access Control (RBAC) interface that demonstrates how to handle setters and getters for roles and addresses.
-- **crowdsale** - A collection of smart contracts used to manage token crowdsales that allow investors to purchase tokens with ETH. Includes a base contract which implements fundamental crowdsale functionality in its simplest form. The base contract can be extended in order to satisfy your crowdsale’s specific requirements.
-	- **distribution** - Includes extensions of the base crowdsale contract which can be used to customize the completion of a crowdsale.
-	- **emission** - Includes extensions of the base crowdsale contract which can be used to mint and manage how tokens are issued to purchasers.
-	- **price** - Includes extensions of the crowdsale contract that can be used to manage changes in token prices.
-	- **validation**  - Includes extensions of the crowdsale contract that can be used to enforce restraints and limit access to token purchases.
-- **examples** - A collection of simple smart contracts that demonstrate how to add new features to base contracts through multiple inheritance.
-- **introspection**  - An interface that can be used to make a contract comply with the ERC-165 standard as well as a contract that implements ERC-165 using a lookup table.
-- **lifecycle** - A collection of base contracts used to manage the existence and behavior of your contracts and their funds.
-- **math** - Libraries with safety checks on operations that throw on errors.
-- **mocks** - A collection of abstract contracts that are primarily used for unit testing. They also serve as good usage examples and demonstrate how to combine contracts with inheritence when developing your own custom applciations.
-- **ownership** - A collection of smart contracts that can be used to manage contract and token ownership
-- **payment** - A collection of smart contracts that can be used to manage payments through escrow arrangements, withdrawals, and claims. Includes support for both single payees and multiple payees.
-- **proposals** - A collection of smart contracts that reflect community Ethereum Improvement Proposals (EIPs). These contracts are under development and standardization. They are not recommended for production, but they are useful for experimentation with pending EIP standards. Go [here](https://github.com/OpenZeppelin/openzeppelin-solidity/wiki/ERC-Process) for more information.
-
-- **token** - A collection of approved ERC standard tokens -- their interfaces and implementations.
-	- **ERC20** - A standard interface for fungible tokens:
-		- *Interfaces* - Includes the ERC-20 token standard basic interface. I.e., what the contract’s ABI can represent.
-		- *Implementations* - Includes ERC-20 token implementations that include all required and some optional ERC-20 functionality.
-	- **ERC721** - A standard interface for non-fungible tokens 
-		- *Interfaces* - Includes the ERC-721 token standard basic interface. I.e., what the contract’s ABI can represent.
-		- *Implementations* - Includes ERC-721 token implementations that include all required and some optional ERC-721 functionality.
-
-## Tests
-Unit test are critical to the OpenZeppelin framework. They help ensure code quality and mitigate against security vulnerabilities. The directory structure within the `/tests` directory corresponds to the `/contracts` directory. OpenZeppelin uses Mocha’s JavaScript testing framework and Chai’s assertion library. To learn more about how to tests are structured, please reference OpenZeppelin’s Testing Guide.
-
-## How To Use And Modify OpenZeppelin Contracts
-When using OpenZeppelin to build your own distributed applications, for security reasons we encourage you NOT to modify the framework’s base contracts, libraries, and interfaces. In order to leverage and extend their functionality, we encourage you to inherit from them or compose them together with your own contracts.
-
-The Solidity programming language supports multiple inheritance. This is very powerful yet it can also be confusing: the more complexity you introduce to your distributed applications through multiple inheritance, the greater your application’s attack surface is.
-
-You’ll notice in the `/mocks` directory there are a collection of abstract contracts used primarily for unit testing purposes that can also be used as the foundation for your own custom implementations. These mock contracts demonstrate how OpenZeppelin’s secure base contracts can be used with multiple inheritance.
-
-To learn more about combining OpenZeppelin contracts with your own custom contracts using multiple inheritance we encourage you to read the following: [On crowdsales and multiple inheritance](https://blog.zeppelin.solutions/on-crowdsales-and-multiple-inheritance-af90c694e35f)
+On our site you will find a few [guides] to learn about the diferent parts of OpenZeppelin, as well as [documentation for the API][API docs]. Keep in mind that the API docs are work in progress, and don’t hesitate to ask questions in [our Slack][Slack].
 
 ## Security
-OpenZeppelin is meant to provide secure, tested and community-audited code, but please use common sense when doing anything that deals with real money! We take no responsibility for your implementation decisions and any security problem you might experience.
+
+OpenZeppelin the project is maintained by [Zeppelin] the company, and developed following our high standards for code quality and security. OpenZeppelin is meant to provide tested and community-audited code, but please use common sense when doing anything that deals with real money! We take no responsibility for your implementation decisions and any security problems you might experience.
 
 The core development principles and strategies that OpenZeppelin is based on include: security in depth, simple and modular code, clarity-driven naming conventions, comprehensive unit testing, pre-and-post-condition sanity checks, code consistency, and regular audits.
 
-If you find a security issue, please email [security@openzeppelin.org](mailto:security@openzeppelin.org).
+Please report any security issues you find to security@openzeppelin.org.
 
-## Developer Resources
+## Contribute
 
-Building a distributed application, protocol or organization with OpenZeppelin?
-
-- Read documentation: https://openzeppelin.org/api/docs/open-zeppelin.html
-
-- Ask for help and follow progress at: https://slack.openzeppelin.org/
-
-Interested in contributing to OpenZeppelin?
-
-- Framework proposal and roadmap: https://medium.com/zeppelin-blog/zeppelin-framework-proposal-and-development-roadmap-fdfa9a3a32ab#.iain47pak
-- Issue tracker: https://github.com/OpenZeppelin/openzeppelin-solidity/issues
-- Contribution guidelines: https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/CONTRIBUTING.md
-- Wiki: https://github.com/OpenZeppelin/openzeppelin-solidity/wiki
+OpenZeppelin exists thanks to its contributors. There are many ways you can participate and help build high quality software. Check out the [contribution guide]!
 
 ## License
-Code released under the [MIT License](https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/LICENSE).
+
+OpenZeppelin is released under the [MIT License](LICENSE).
+
+
+[API docs]: https://openzeppelin.org/api/docs/token_ERC721_ERC721BasicToken.html
+[guides]: https://openzeppelin.org/api/docs/get-started.html
+[Slack]: https://slack.openzeppelin.org
+[Zeppelin]: https://zeppelin.solutions
+[contribution guide]: CONTRIBUTING.md
+[Truffle]: https://truffleframework.com/docs/truffle/quickstart
+[Embark]: https://embark.status.im/docs/quick_start.html

RELEASING.md

@@ -0,0 +1,96 @@
+# Releasing
+
+This document describes our release process, and contains the steps to be followed by an OpenZeppelin maintainer at the several stages of a release.
+
+We release a new version of OpenZeppelin monthly. Release cycles are tracked in the [issue milestones](https://github.com/OpenZeppelin/openzeppelin-solidity/milestones).
+
+Each release has at least one release candidate published first, intended for community review and any critical fixes that may come out of it. At the moment we leave 1 week between the first release candidate and the final release.
+
+Before starting make sure to verify the following items.
+* Your local `master` branch is in sync with your `upstream` remote (it may have another name depending on your setup).
+* Your repo is clean, particularly with no untracked files in the contracts and tests directories. Verify with `git clean -n`.
+
+
+## Creating the release branch
+
+We'll refer to a release `vX.Y.Z`.
+
+```
+git checkout master
+git checkout -b release-vX.Y.Z
+```
+
+## Creating a release candidate
+
+Once in the release branch, change the version string in `package.json`, `package-lock.json` and `ethpm.json` to `X.Y.Z-rc.R`. (This will be `X.Y.Z-rc.1` for the first release candidate.) Commit these changes and tag the commit as `vX.Y.Z-rc.R`.
+
+```
+git add package.json package-lock.json ethpm.json
+git commit -m "Release candidate vX.Y.Z-rc.R"
+git tag -a vX.Y.Z-rc.R
+git push upstream release-vX.Y.Z
+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. You should see the contracts compile automatically.
+
+```
+npm publish --tag next
+```
+
+Publish the release notes on GitHub and ask our community manager to announce the release candidate on at least Slack and Twitter.
+
+## Creating the final release
+
+Make sure to have the latest changes from `upstream` in your local release branch.
+
+```
+git checkout release-vX.Y.Z
+git pull upstream
+```
+
+Change the version string in `package.json`, `package-lock.json` and `ethpm.json` removing the "-rc.R" suffix. Commit these changes and tag the commit as `vX.Y.Z`.
+
+```
+git add package.json package-lock.json ethpm.json
+git commit -m "Release vX.Y.Z"
+git tag -a vX.Y.Z
+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. You should see the contracts compile automatically.
+
+```
+npm publish
+```
+
+Publish the release notes on GitHub and ask our community manager to announce the release!
+
+Delete the `next` tag in the npm package as there is no longer a release candidate.
+
+```
+npm dist-tag rm --otp $2FA_CODE openzeppelin-solidity next
+```
+
+## Merging the release branch
+
+After the final release, the release branch should be merged back into `master`. This merge must not be squashed because it would lose the tagged release commit. Since the GitHub repo is set up to only allow squashed merges, the merge should be done locally and pushed.
+
+Make sure to have the latest changes from `upstream` in your local release branch.
+
+```
+git checkout release-vX.Y.Z
+git pull upstream
+```
+
+```
+git checkout master
+git merge --no-ff release-vX.Y.Z
+git push upstream master
+```
+
+The release branch can then be deleted on GitHub.

contracts/ARCHITECTURE.md

@@ -0,0 +1,27 @@
+## Architecture
+
+The following provides visibility into how OpenZeppelin's contracts are organized:
+
+- **access** - Smart contracts that enable functionality that can be used for selective restrictions and basic authorization control functions.
+- **crowdsale** - A collection of smart contracts used to manage token crowdsales that allow investors to purchase tokens with ETH. Includes a base contract which implements fundamental crowdsale functionality in its simplest form. The base contract can be extended in order to satisfy your crowdsale’s specific requirements.
+	- **distribution** - Includes extensions of the base crowdsale contract which can be used to customize the completion of a crowdsale.
+	- **emission** - Includes extensions of the base crowdsale contract which can be used to mint and manage how tokens are issued to purchasers.
+	- **price** - Includes extensions of the crowdsale contract that can be used to manage changes in token prices.
+	- **validation**  - Includes extensions of the crowdsale contract that can be used to enforce restraints and limit access to token purchases.
+- **examples** - A collection of simple smart contracts that demonstrate how to add new features to base contracts through multiple inheritance.
+- **introspection**  - An interface that can be used to make a contract comply with the ERC-165 standard as well as a contract that implements ERC-165 using a lookup table.
+- **lifecycle** - A collection of base contracts used to manage the existence and behavior of your contracts and their funds.
+- **math** - Libraries with safety checks on operations that throw on errors.
+- **mocks** - A collection of abstract contracts that are primarily used for unit testing. They also serve as good usage examples and demonstrate how to combine contracts with inheritance when developing your own custom applications.
+- **ownership** - A collection of smart contracts that can be used to manage contract and token ownership
+- **payment** - A collection of smart contracts that can be used to manage payments through escrow arrangements, withdrawals, and claims. Includes support for both single payees and multiple payees.
+- **proposals** - A collection of smart contracts that reflect community Ethereum Improvement Proposals (EIPs). These contracts are under development and standardization. They are not recommended for production, but they are useful for experimentation with pending EIP standards. Go [here](https://github.com/OpenZeppelin/openzeppelin-solidity/wiki/ERC-Process) for more information.
+
+- **token** - A collection of approved ERC standard tokens -- their interfaces and implementations.
+	- **ERC20** - A standard interface for fungible tokens:
+		- *Interfaces* - Includes the ERC-20 token standard basic interface. I.e., what the contract’s ABI can represent.
+		- *Implementations* - Includes ERC-20 token implementations that include all required and some optional ERC-20 functionality.
+	- **ERC721** - A standard interface for non-fungible tokens
+		- *Interfaces* - Includes the ERC-721 token standard basic interface. I.e., what the contract’s ABI can represent.
+		- *Implementations* - Includes ERC-721 token implementations that include all required and some optional ERC-721 functionality.
+

contracts/AddressUtils.sol

@@ -1,29 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * Utility library of inline functions on addresses
- */
-library AddressUtils {
-
-  /**
-   * Returns whether the target address is a contract
-   * @dev This function will return false if invoked during the constructor of a contract,
-   * as the code is not actually created until after the constructor finishes.
-   * @param _addr address to check
-   * @return whether the target address is a contract
-   */
-  function isContract(address _addr) internal view returns (bool) {
-    uint256 size;
-    // XXX Currently there is no better way to check if there is a contract in an address
-    // than to check the size of the code at that address.
-    // See https://ethereum.stackexchange.com/a/14016/36603
-    // for more details about how this works.
-    // TODO Check this again before the Serenity release, because all addresses will be
-    // contracts then.
-    // solium-disable-next-line security/no-inline-assembly
-    assembly { size := extcodesize(_addr) }
-    return size > 0;
-  }
-
-}

contracts/AutoIncrementing.sol

@@ -1,29 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title AutoIncrementing
- * @author Matt Condon (@shrugs)
- * @dev Provides an auto-incrementing uint256 id acquired by the `Counter#nextId` getter.
- * Use this for issuing ERC721Token ids or keeping track of request ids, anything you want, really.
- *
- * Include with `using AutoIncrementing for AutoIncrementing.Counter;`
- * @notice Does not allow an Id of 0, which is popularly used to signify a null state in solidity.
- * Does not protect from overflows, but if you have 2^256 ids, you have other problems.
- * (But actually, it's generally impossible to increment a counter this many times, energy wise
- * so it's not something you have to worry about.)
- */
-library AutoIncrementing {
-
-  struct Counter {
-    uint256 prevId; // default: 0
-  }
-
-  function nextId(Counter storage _counter)
-    internal
-    returns (uint256)
-  {
-    _counter.prevId = _counter.prevId + 1;
-    return _counter.prevId;
-  }
-}

contracts/Bounty.sol

@@ -1,72 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "./payment/PullPayment.sol";
-import "./lifecycle/Destructible.sol";
-
-
-/**
- * @title Bounty
- * @dev This bounty will pay out to a researcher if they break invariant logic of the contract.
- */
-contract Bounty is PullPayment, Destructible {
-  bool public claimed;
-  mapping(address => address) public researchers;
-
-  event TargetCreated(address createdAddress);
-
-  /**
-   * @dev Fallback function allowing the contract to receive funds, if they haven't already been claimed.
-   */
-  function() external payable {
-    require(!claimed);
-  }
-
-  /**
-   * @dev Create and deploy the target contract (extension of Target contract), and sets the
-   * msg.sender as a researcher
-   * @return A target contract
-   */
-  function createTarget() public returns(Target) {
-    Target target = Target(deployContract());
-    researchers[target] = msg.sender;
-    emit TargetCreated(target);
-    return target;
-  }
-
-  /**
-   * @dev Transfers the contract funds to the researcher that proved the contract is broken.
-   * @param _target contract
-   */
-  function claim(Target _target) public {
-    address researcher = researchers[_target];
-    require(researcher != address(0));
-    // Check Target contract invariants
-    require(!_target.checkInvariant());
-    asyncTransfer(researcher, address(this).balance);
-    claimed = true;
-  }
-
-  /**
-   * @dev Internal function to deploy the target contract.
-   * @return A target contract address
-   */
-  function deployContract() internal returns(address);
-
-}
-
-
-/**
- * @title Target
- * @dev Your main contract should inherit from this class and implement the checkInvariant method.
- */
-contract Target {
-
-   /**
-    * @dev Checks all values a contract assumes to be true all the time. If this function returns
-    * false, the contract is broken in some way and is in an inconsistent state.
-    * In order to win the bounty, security researchers will try to cause this broken state.
-    * @return True if all invariant values are correct, false otherwise.
-    */
-  function checkInvariant() public returns(bool);
-}

contracts/ECRecovery.sol

@@ -1,72 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title Elliptic curve signature operations
- * @dev Based on https://gist.github.com/axic/5b33912c6f61ae6fd96d6c4a47afde6d
- * TODO Remove this library once solidity supports passing a signature to ecrecover.
- * See https://github.com/ethereum/solidity/issues/864
- */
-
-library ECRecovery {
-
-  /**
-   * @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 _sig bytes signature, the signature is generated using web3.eth.sign()
-   */
-  function recover(bytes32 _hash, bytes _sig)
-    internal
-    pure
-    returns (address)
-  {
-    bytes32 r;
-    bytes32 s;
-    uint8 v;
-
-    // Check the signature length
-    if (_sig.length != 65) {
-      return (address(0));
-    }
-
-    // Divide the signature in r, s and v variables
-    // ecrecover takes the signature parameters, and the only way to get them
-    // currently is to use assembly.
-    // solium-disable-next-line security/no-inline-assembly
-    assembly {
-      r := mload(add(_sig, 32))
-      s := mload(add(_sig, 64))
-      v := byte(0, mload(add(_sig, 96)))
-    }
-
-    // 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/LimitBalance.sol

@@ -1,31 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title LimitBalance
- * @dev Simple contract to limit the balance of child contract.
- * Note this doesn't prevent other contracts to send funds by using selfdestruct(address);
- * See: https://github.com/ConsenSys/smart-contract-best-practices#remember-that-ether-can-be-forcibly-sent-to-an-account
- */
-contract LimitBalance {
-
-  uint256 public limit;
-
-  /**
-   * @dev Constructor that sets the passed value as a limit.
-   * @param _limit uint256 to represent the limit.
-   */
-  constructor(uint256 _limit) public {
-    limit = _limit;
-  }
-
-  /**
-   * @dev Checks if limit was reached. Case true, it throws.
-   */
-  modifier limitedPayable() {
-    require(address(this).balance <= limit);
-    _;
-
-  }
-
-}

contracts/MerkleProof.sol

@@ -1,43 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title MerkleProof
- * @dev Merkle proof verification based on
- * 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
-   * 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 _root Merkle root
-   * @param _leaf Leaf of Merkle tree
-   */
-  function verifyProof(
-    bytes32[] _proof,
-    bytes32 _root,
-    bytes32 _leaf
-  )
-    internal
-    pure
-    returns (bool)
-  {
-    bytes32 computedHash = _leaf;
-
-    for (uint256 i = 0; i < _proof.length; i++) {
-      bytes32 proofElement = _proof[i];
-
-      if (computedHash < proofElement) {
-        // Hash(current computed hash + current element of the proof)
-        computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
-      } else {
-        // Hash(current element of the proof + current computed hash)
-        computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
-      }
-    }
-
-    // Check if the computed hash (root) is equal to the provided root
-    return computedHash == _root;
-  }
-}

contracts/ReentrancyGuard.sol

@@ -1,39 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title Helps contracts guard against reentrancy attacks.
- * @author Remco Bloemen <remco@2π.com>, Eenae <alexey@mixbytes.io>
- * @dev If you mark a function `nonReentrant`, you should also
- * mark it `external`.
- */
-contract ReentrancyGuard {
-
-  /// @dev Constant for unlocked guard state - non-zero to prevent extra gas costs.
-  /// See: https://github.com/OpenZeppelin/openzeppelin-solidity/issues/1056
-  uint private constant REENTRANCY_GUARD_FREE = 1;
-
-  /// @dev Constant for locked guard state
-  uint private constant REENTRANCY_GUARD_LOCKED = 2;
-
-  /**
-   * @dev We use a single lock for the whole contract.
-   */
-  uint private reentrancyLock = REENTRANCY_GUARD_FREE;
-
-  /**
-   * @dev Prevents a contract from calling itself, directly or indirectly.
-   * If you mark a function `nonReentrant`, you should also
-   * mark it `external`. Calling one `nonReentrant` function from
-   * another is not supported. Instead, you can implement a
-   * `private` function doing the actual work, and an `external`
-   * wrapper marked as `nonReentrant`.
-   */
-  modifier nonReentrant() {
-    require(reentrancyLock == REENTRANCY_GUARD_FREE);
-    reentrancyLock = REENTRANCY_GUARD_LOCKED;
-    _;
-    reentrancyLock = REENTRANCY_GUARD_FREE;
-  }
-
-}

contracts/access/Roles.sol

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

contracts/access/SignatureBouncer.sol

@@ -1,159 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../ownership/Ownable.sol";
-import "../access/rbac/RBAC.sol";
-import "../ECRecovery.sol";
-
-
-/**
- * @title SignatureBouncer
- * @author PhABC, Shrugs and aflesher
- * @dev Bouncer allows users to submit a signature as a permission to do an action.
- * If the signature is from one of the authorized bouncer addresses, the signature
- * is valid. The owner of the contract adds/removes bouncers.
- * Bouncer addresses can be individual servers signing grants or different
- * users within a decentralized club that have permission to invite other members.
- * This technique is useful for whitelists and airdrops; instead of putting all
- * valid addresses on-chain, simply sign a grant of the form
- * keccak256(abi.encodePacked(`:contractAddress` + `:granteeAddress`)) using a valid bouncer address.
- * Then restrict access to your crowdsale/whitelist/airdrop using the
- * `onlyValidSignature` modifier (or implement your own using isValidSignature).
- * In addition to `onlyValidSignature`, `onlyValidSignatureAndMethod` and
- * `onlyValidSignatureAndData` can be used to restrict access to only a given method
- * or a given method with given parameters respectively.
- * See the tests Bouncer.test.js for specific usage examples.
- * @notice A method that uses the `onlyValidSignatureAndData` modifier must make the _sig
- * parameter the "last" parameter. You cannot sign a message that has its own
- * signature in it so the last 128 bytes of msg.data (which represents the
- * length of the _sig data and the _sig data itself) is ignored when validating.
- * Also non fixed sized parameters make constructing the data in the signature
- * much more complex. See https://ethereum.stackexchange.com/a/50616 for more details.
- */
-contract SignatureBouncer is Ownable, RBAC {
-  using ECRecovery for bytes32;
-
-  string public constant ROLE_BOUNCER = "bouncer";
-  uint constant METHOD_ID_SIZE = 4;
-  // signature size is 65 bytes (tightly packed v + r + s), but gets padded to 96 bytes
-  uint constant SIGNATURE_SIZE = 96;
-
-  /**
-   * @dev requires that a valid signature of a bouncer was provided
-   */
-  modifier onlyValidSignature(bytes _sig)
-  {
-    require(isValidSignature(msg.sender, _sig));
-    _;
-  }
-
-  /**
-   * @dev requires that a valid signature with a specifed method of a bouncer was provided
-   */
-  modifier onlyValidSignatureAndMethod(bytes _sig)
-  {
-    require(isValidSignatureAndMethod(msg.sender, _sig));
-    _;
-  }
-
-  /**
-   * @dev requires that a valid signature with a specifed method and params of a bouncer was provided
-   */
-  modifier onlyValidSignatureAndData(bytes _sig)
-  {
-    require(isValidSignatureAndData(msg.sender, _sig));
-    _;
-  }
-
-  /**
-   * @dev allows the owner to add additional bouncer addresses
-   */
-  function addBouncer(address _bouncer)
-    public
-    onlyOwner
-  {
-    require(_bouncer != address(0));
-    addRole(_bouncer, ROLE_BOUNCER);
-  }
-
-  /**
-   * @dev allows the owner to remove bouncer addresses
-   */
-  function removeBouncer(address _bouncer)
-    public
-    onlyOwner
-  {
-    require(_bouncer != address(0));
-    removeRole(_bouncer, ROLE_BOUNCER);
-  }
-
-  /**
-   * @dev is the signature of `this + sender` from a bouncer?
-   * @return bool
-   */
-  function isValidSignature(address _address, bytes _sig)
-    internal
-    view
-    returns (bool)
-  {
-    return isValidDataHash(
-      keccak256(abi.encodePacked(address(this), _address)),
-      _sig
-    );
-  }
-
-  /**
-   * @dev is the signature of `this + sender + methodId` from a bouncer?
-   * @return bool
-   */
-  function isValidSignatureAndMethod(address _address, bytes _sig)
-    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), _address, data)),
-      _sig
-    );
-  }
-
-  /**
-    * @dev is the signature of `this + sender + methodId + params(s)` from a bouncer?
-    * @notice the _sig parameter of the method being validated must be the "last" parameter
-    * @return bool
-    */
-  function isValidSignatureAndData(address _address, bytes _sig)
-    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), _address, data)),
-      _sig
-    );
-  }
-
-  /**
-   * @dev internal function to convert a hash to an eth signed message
-   * and then recover the signature and check it against the bouncer role
-   * @return bool
-   */
-  function isValidDataHash(bytes32 _hash, bytes _sig)
-    internal
-    view
-    returns (bool)
-  {
-    address signer = _hash
-      .toEthSignedMessageHash()
-      .recover(_sig);
-    return hasRole(signer, ROLE_BOUNCER);
-  }
-}

contracts/access/Whitelist.sol

@@ -1,91 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "../ownership/Ownable.sol";
-import "../access/rbac/RBAC.sol";
-
-
-/**
- * @title Whitelist
- * @dev The Whitelist contract has a whitelist of addresses, and provides basic authorization control functions.
- * This simplifies the implementation of "user permissions".
- */
-contract Whitelist is Ownable, RBAC {
-  string public constant ROLE_WHITELISTED = "whitelist";
-
-  /**
-   * @dev Throws if operator is not whitelisted.
-   * @param _operator address
-   */
-  modifier onlyIfWhitelisted(address _operator) {
-    checkRole(_operator, ROLE_WHITELISTED);
-    _;
-  }
-
-  /**
-   * @dev add an address to the whitelist
-   * @param _operator address
-   * @return true if the address was added to the whitelist, false if the address was already in the whitelist
-   */
-  function addAddressToWhitelist(address _operator)
-    public
-    onlyOwner
-  {
-    addRole(_operator, ROLE_WHITELISTED);
-  }
-
-  /**
-   * @dev getter to determine if address is in whitelist
-   */
-  function whitelist(address _operator)
-    public
-    view
-    returns (bool)
-  {
-    return hasRole(_operator, ROLE_WHITELISTED);
-  }
-
-  /**
-   * @dev add addresses to the whitelist
-   * @param _operators addresses
-   * @return true if at least one address was added to the whitelist,
-   * false if all addresses were already in the whitelist
-   */
-  function addAddressesToWhitelist(address[] _operators)
-    public
-    onlyOwner
-  {
-    for (uint256 i = 0; i < _operators.length; i++) {
-      addAddressToWhitelist(_operators[i]);
-    }
-  }
-
-  /**
-   * @dev remove an address from the whitelist
-   * @param _operator address
-   * @return true if the address was removed from the whitelist,
-   * false if the address wasn't in the whitelist in the first place
-   */
-  function removeAddressFromWhitelist(address _operator)
-    public
-    onlyOwner
-  {
-    removeRole(_operator, ROLE_WHITELISTED);
-  }
-
-  /**
-   * @dev remove addresses from the whitelist
-   * @param _operators addresses
-   * @return true if at least one address was removed from the whitelist,
-   * false if all addresses weren't in the whitelist in the first place
-   */
-  function removeAddressesFromWhitelist(address[] _operators)
-    public
-    onlyOwner
-  {
-    for (uint256 i = 0; i < _operators.length; i++) {
-      removeAddressFromWhitelist(_operators[i]);
-    }
-  }
-
-}

contracts/access/rbac/RBAC.sol

@@ -1,106 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "./Roles.sol";
-
-
-/**
- * @title RBAC (Role-Based Access Control)
- * @author Matt Condon (@Shrugs)
- * @dev Stores and provides setters and getters for roles and addresses.
- * Supports unlimited numbers of roles and addresses.
- * See //contracts/mocks/RBACMock.sol for an example of usage.
- * This RBAC method uses strings to key roles. It may be beneficial
- * for you to write your own implementation of this interface using Enums or similar.
- */
-contract RBAC {
-  using Roles for Roles.Role;
-
-  mapping (string => Roles.Role) private roles;
-
-  event RoleAdded(address indexed operator, string role);
-  event RoleRemoved(address indexed operator, string role);
-
-  /**
-   * @dev reverts if addr does not have role
-   * @param _operator address
-   * @param _role the name of the role
-   * // reverts
-   */
-  function checkRole(address _operator, string _role)
-    public
-    view
-  {
-    roles[_role].check(_operator);
-  }
-
-  /**
-   * @dev determine if addr has role
-   * @param _operator address
-   * @param _role the name of the role
-   * @return bool
-   */
-  function hasRole(address _operator, string _role)
-    public
-    view
-    returns (bool)
-  {
-    return roles[_role].has(_operator);
-  }
-
-  /**
-   * @dev add a role to an address
-   * @param _operator address
-   * @param _role the name of the role
-   */
-  function addRole(address _operator, string _role)
-    internal
-  {
-    roles[_role].add(_operator);
-    emit RoleAdded(_operator, _role);
-  }
-
-  /**
-   * @dev remove a role from an address
-   * @param _operator address
-   * @param _role the name of the role
-   */
-  function removeRole(address _operator, string _role)
-    internal
-  {
-    roles[_role].remove(_operator);
-    emit RoleRemoved(_operator, _role);
-  }
-
-  /**
-   * @dev modifier to scope access to a single role (uses msg.sender as addr)
-   * @param _role the name of the role
-   * // reverts
-   */
-  modifier onlyRole(string _role)
-  {
-    checkRole(msg.sender, _role);
-    _;
-  }
-
-  /**
-   * @dev modifier to scope access to a set of roles (uses msg.sender as addr)
-   * @param _roles the names of the roles to scope access to
-   * // reverts
-   *
-   * @TODO - when solidity supports dynamic arrays as arguments to modifiers, provide this
-   *  see: https://github.com/ethereum/solidity/issues/2467
-   */
-  // modifier onlyRoles(string[] _roles) {
-  //     bool hasAnyRole = false;
-  //     for (uint8 i = 0; i < _roles.length; i++) {
-  //         if (hasRole(msg.sender, _roles[i])) {
-  //             hasAnyRole = true;
-  //             break;
-  //         }
-  //     }
-
-  //     require(hasAnyRole);
-
-  //     _;
-  // }
-}

contracts/access/rbac/Roles.sol

@@ -1,55 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-/**
- * @title Roles
- * @author Francisco Giordano (@frangio)
- * @dev Library for managing addresses assigned to a Role.
- * See RBAC.sol for example usage.
- */
-library Roles {
-  struct Role {
-    mapping (address => bool) bearer;
-  }
-
-  /**
-   * @dev give an address access to this role
-   */
-  function add(Role storage _role, address _addr)
-    internal
-  {
-    _role.bearer[_addr] = true;
-  }
-
-  /**
-   * @dev remove an address' access to this role
-   */
-  function remove(Role storage _role, address _addr)
-    internal
-  {
-    _role.bearer[_addr] = false;
-  }
-
-  /**
-   * @dev check if an address has this role
-   * // reverts
-   */
-  function check(Role storage _role, address _addr)
-    internal
-    view
-  {
-    require(has(_role, _addr));
-  }
-
-  /**
-   * @dev check if an address has this role
-   * @return bool
-   */
-  function has(Role storage _role, address _addr)
-    internal
-    view
-    returns (bool)
-  {
-    return _role.bearer[_addr];
-  }
-}

contracts/access/roles/CapperRole.sol

@@ -0,0 +1,43 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+
+contract CapperRole {
+    using Roles for Roles.Role;
+
+    event CapperAdded(address indexed account);
+    event CapperRemoved(address indexed account);
+
+    Roles.Role private _cappers;
+
+    constructor () internal {
+        _addCapper(msg.sender);
+    }
+
+    modifier onlyCapper() {
+        require(isCapper(msg.sender));
+        _;
+    }
+
+    function isCapper(address account) public view returns (bool) {
+        return _cappers.has(account);
+    }
+
+    function addCapper(address account) public onlyCapper {
+        _addCapper(account);
+    }
+
+    function renounceCapper() public {
+        _removeCapper(msg.sender);
+    }
+
+    function _addCapper(address account) internal {
+        _cappers.add(account);
+        emit CapperAdded(account);
+    }
+
+    function _removeCapper(address account) internal {
+        _cappers.remove(account);
+        emit CapperRemoved(account);
+    }
+}

contracts/access/roles/MinterRole.sol

@@ -0,0 +1,43 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+
+contract MinterRole {
+    using Roles for Roles.Role;
+
+    event MinterAdded(address indexed account);
+    event MinterRemoved(address indexed account);
+
+    Roles.Role private _minters;
+
+    constructor () internal {
+        _addMinter(msg.sender);
+    }
+
+    modifier onlyMinter() {
+        require(isMinter(msg.sender));
+        _;
+    }
+
+    function isMinter(address account) public view returns (bool) {
+        return _minters.has(account);
+    }
+
+    function addMinter(address account) public onlyMinter {
+        _addMinter(account);
+    }
+
+    function renounceMinter() public {
+        _removeMinter(msg.sender);
+    }
+
+    function _addMinter(address account) internal {
+        _minters.add(account);
+        emit MinterAdded(account);
+    }
+
+    function _removeMinter(address account) internal {
+        _minters.remove(account);
+        emit MinterRemoved(account);
+    }
+}

contracts/access/roles/PauserRole.sol

@@ -0,0 +1,43 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+
+contract PauserRole {
+    using Roles for Roles.Role;
+
+    event PauserAdded(address indexed account);
+    event PauserRemoved(address indexed account);
+
+    Roles.Role private _pausers;
+
+    constructor () internal {
+        _addPauser(msg.sender);
+    }
+
+    modifier onlyPauser() {
+        require(isPauser(msg.sender));
+        _;
+    }
+
+    function isPauser(address account) public view returns (bool) {
+        return _pausers.has(account);
+    }
+
+    function addPauser(address account) public onlyPauser {
+        _addPauser(account);
+    }
+
+    function renouncePauser() public {
+        _removePauser(msg.sender);
+    }
+
+    function _addPauser(address account) internal {
+        _pausers.add(account);
+        emit PauserAdded(account);
+    }
+
+    function _removePauser(address account) internal {
+        _pausers.remove(account);
+        emit PauserRemoved(account);
+    }
+}

contracts/access/roles/SignerRole.sol

@@ -0,0 +1,43 @@
+pragma solidity ^0.5.0;
+
+import "../Roles.sol";
+
+contract SignerRole {
+    using Roles for Roles.Role;
+
+    event SignerAdded(address indexed account);
+    event SignerRemoved(address indexed account);
+
+    Roles.Role private _signers;
+
+    constructor () internal {
+        _addSigner(msg.sender);
+    }
+
+    modifier onlySigner() {
+        require(isSigner(msg.sender));
+        _;
+    }
+
+    function isSigner(address account) public view returns (bool) {
+        return _signers.has(account);
+    }
+
+    function addSigner(address account) public onlySigner {
+        _addSigner(account);
+    }
+
+    function renounceSigner() public {
+        _removeSigner(msg.sender);
+    }
+
+    function _addSigner(address account) internal {
+        _signers.add(account);
+        emit SignerAdded(account);
+    }
+
+    function _removeSigner(address account) internal {
+        _signers.remove(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

@@ -1,9 +1,9 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/IERC20.sol";
 import "../math/SafeMath.sol";
 import "../token/ERC20/SafeERC20.sol";
-
+import "../utils/ReentrancyGuard.sol";
 
 /**
  * @title Crowdsale
@@ -17,187 +17,182 @@ import "../token/ERC20/SafeERC20.sol";
  * the methods to add functionality. Consider using 'super' where appropriate to concatenate
  * behavior.
  */
-contract Crowdsale {
-  using SafeMath for uint256;
-  using SafeERC20 for ERC20;
+contract Crowdsale is ReentrancyGuard {
+    using SafeMath for uint256;
+    using SafeERC20 for IERC20;
 
-  // The token being sold
-  ERC20 public token;
+    // The token being sold
+    IERC20 private _token;
 
-  // Address where funds are collected
-  address public wallet;
+    // Address where funds are collected
+    address payable private _wallet;
 
-  // How many token units a buyer gets per wei.
-  // 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 DetailedERC20 token with 3 decimals called TOK
-  // 1 wei will give you 1 unit, or 0.001 TOK.
-  uint256 public rate;
+    // How many token units a buyer gets per wei.
+    // 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
+    // 1 wei will give you 1 unit, or 0.001 TOK.
+    uint256 private _rate;
 
-  // Amount of wei raised
-  uint256 public weiRaised;
+    // Amount of wei raised
+    uint256 private _weiRaised;
 
-  /**
-   * Event for token purchase logging
-   * @param purchaser who paid for the tokens
-   * @param beneficiary who got the tokens
-   * @param value weis paid for purchase
-   * @param amount amount of tokens purchased
-   */
-  event TokenPurchase(
-    address indexed purchaser,
-    address indexed beneficiary,
-    uint256 value,
-    uint256 amount
-  );
+    /**
+     * Event for token purchase logging
+     * @param purchaser who paid for the tokens
+     * @param beneficiary who got the tokens
+     * @param value weis paid for purchase
+     * @param amount amount of tokens purchased
+     */
+    event TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
 
-  /**
-   * @param _rate Number of token units a buyer gets per wei
-   * @param _wallet Address where collected funds will be forwarded to
-   * @param _token Address of the token being sold
-   */
-  constructor(uint256 _rate, address _wallet, ERC20 _token) public {
-    require(_rate > 0);
-    require(_wallet != address(0));
-    require(_token != address(0));
+    /**
+     * @param rate Number of token units a buyer gets per wei
+     * @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
+     * 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 token Address of the token being sold
+     */
+    constructor (uint256 rate, address payable wallet, IERC20 token) public {
+        require(rate > 0);
+        require(wallet != address(0));
+        require(address(token) != address(0));
 
-    rate = _rate;
-    wallet = _wallet;
-    token = _token;
-  }
+        _rate = rate;
+        _wallet = wallet;
+        _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***
-   */
-  function () external payable {
-    buyTokens(msg.sender);
-  }
+    /**
+     * @return the token being sold.
+     */
+    function token() public view returns (IERC20) {
+        return _token;
+    }
 
-  /**
-   * @dev low level token purchase ***DO NOT OVERRIDE***
-   * @param _beneficiary Address performing the token purchase
-   */
-  function buyTokens(address _beneficiary) public payable {
+    /**
+     * @return the address where funds are collected.
+     */
+    function wallet() public view returns (address payable) {
+        return _wallet;
+    }
 
-    uint256 weiAmount = msg.value;
-    _preValidatePurchase(_beneficiary, weiAmount);
+    /**
+     * @return the number of token units a buyer gets per wei.
+     */
+    function rate() public view returns (uint256) {
+        return _rate;
+    }
 
-    // calculate token amount to be created
-    uint256 tokens = _getTokenAmount(weiAmount);
+    /**
+     * @return the amount of wei raised.
+     */
+    function weiRaised() public view returns (uint256) {
+        return _weiRaised;
+    }
 
-    // update state
-    weiRaised = weiRaised.add(weiAmount);
+    /**
+     * @dev low level token purchase ***DO NOT OVERRIDE***
+     * 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;
+        _preValidatePurchase(beneficiary, weiAmount);
 
-    _processPurchase(_beneficiary, tokens);
-    emit TokenPurchase(
-      msg.sender,
-      _beneficiary,
-      weiAmount,
-      tokens
-    );
+        // calculate token amount to be created
+        uint256 tokens = _getTokenAmount(weiAmount);
 
-    _updatePurchasingState(_beneficiary, weiAmount);
+        // update state
+        _weiRaised = _weiRaised.add(weiAmount);
 
-    _forwardFunds();
-    _postValidatePurchase(_beneficiary, weiAmount);
-  }
+        _processPurchase(beneficiary, tokens);
+        emit TokensPurchased(msg.sender, beneficiary, weiAmount, tokens);
 
-  // -----------------------------------------
-  // Internal interface (extensible)
-  // -----------------------------------------
+        _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
-  {
-    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
-  {
-    // optional override
-  }
+    /**
+     * @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);
+    }
 
-  /**
-   * @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 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
+    }
 
-  /**
-   * @dev Executed when a purchase has been validated and is ready to be executed. Not necessarily emits/sends tokens.
-   * @param _beneficiary Address receiving the tokens
-   * @param _tokenAmount Number of tokens to be purchased
-   */
-  function _processPurchase(
-    address _beneficiary,
-    uint256 _tokenAmount
-  )
-    internal
-  {
-    _deliverTokens(_beneficiary, _tokenAmount);
-  }
+    /**
+     * @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 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 Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send
+     * tokens.
+     * @param beneficiary Address receiving the tokens
+     * @param tokenAmount Number of tokens to be purchased
+     */
+    function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
+        _deliverTokens(beneficiary, tokenAmount);
+    }
 
-  /**
-   * @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 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 {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 
-  /**
-   * @dev Determines how ETH is stored/forwarded on purchases.
-   */
-  function _forwardFunds() internal {
-    wallet.transfer(msg.value);
-  }
+    /**
+     * @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

@@ -1,42 +1,51 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
-import "../../ownership/Ownable.sol";
 import "../validation/TimedCrowdsale.sol";
 
-
 /**
  * @title FinalizableCrowdsale
- * @dev Extension of Crowdsale where an owner can do extra work
- * after finishing.
+ * @dev Extension of Crowdsale with a one-off finalization action, where one
+ * can do extra work after finishing.
  */
-contract FinalizableCrowdsale is Ownable, TimedCrowdsale {
-  using SafeMath for uint256;
+contract FinalizableCrowdsale is TimedCrowdsale {
+    using SafeMath for uint256;
 
-  bool public isFinalized = false;
+    bool private _finalized;
 
-  event Finalized();
+    event CrowdsaleFinalized();
 
-  /**
-   * @dev Must be called after crowdsale ends, to do some extra finalization
-   * work. Calls the contract's finalization function.
-   */
-  function finalize() public onlyOwner {
-    require(!isFinalized);
-    require(hasClosed());
+    constructor () internal {
+        _finalized = false;
+    }
 
-    finalization();
-    emit Finalized();
+    /**
+     * @return true if the crowdsale is finalized, false otherwise.
+     */
+    function finalized() public view returns (bool) {
+        return _finalized;
+    }
 
-    isFinalized = true;
-  }
+    /**
+     * @dev Must be called after crowdsale ends, to do some extra finalization
+     * work. Calls the contract's finalization function.
+     */
+    function finalize() public {
+        require(!_finalized);
+        require(hasClosed());
 
-  /**
-   * @dev Can be overridden to add finalization logic. The overriding function
-   * should call super.finalization() to ensure the chain of finalization is
-   * executed entirely.
-   */
-  function finalization() internal {
-  }
+        _finalized = true;
 
+        _finalization();
+        emit CrowdsaleFinalized();
+    }
+
+    /**
+     * @dev Can be overridden to add finalization logic. The overriding function
+     * should call super._finalization() to ensure the chain of finalization is
+     * executed entirely.
+     */
+    function _finalization() internal {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/crowdsale/distribution/PostDeliveryCrowdsale.sol

@@ -1,42 +1,43 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../validation/TimedCrowdsale.sol";
-import "../../token/ERC20/ERC20.sol";
 import "../../math/SafeMath.sol";
 
-
 /**
  * @title PostDeliveryCrowdsale
  * @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) public balances;
+    mapping(address => uint256) private _balances;
 
-  /**
-   * @dev Withdraw tokens only after crowdsale ends.
-   */
-  function withdrawTokens() public {
-    require(hasClosed());
-    uint256 amount = balances[msg.sender];
-    require(amount > 0);
-    balances[msg.sender] = 0;
-    _deliverTokens(msg.sender, amount);
-  }
+    /**
+     * @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 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);
-  }
+    /**
+     * @return the balance of an account.
+     */
+    function balanceOf(address account) public view returns (uint256) {
+        return _balances[account];
+    }
+
+    /**
+     * @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

@@ -1,72 +1,82 @@
-pragma solidity ^0.4.24;
-
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "./FinalizableCrowdsale.sol";
-import "../../payment/RefundEscrow.sol";
-
+import "../../payment/escrow/RefundEscrow.sol";
 
 /**
  * @title RefundableCrowdsale
- * @dev Extension of Crowdsale contract that adds a funding goal, and
- * the possibility of users getting a refund if goal is not met.
+ * @dev Extension of Crowdsale contract that adds a funding goal, and the possibility of users getting a refund if goal
+ * is not met.
+ *
+ * Deprecated, use RefundablePostDeliveryCrowdsale instead. Note that if you allow tokens to be traded before the goal
+ * is met, then an attack is possible in which the attacker purchases tokens from the crowdsale and when they sees that
+ * the goal is unlikely to be met, they sell their tokens (possibly at a discount). The attacker will be refunded when
+ * the crowdsale is finalized, and the users that purchased from them will be left with worthless tokens.
  */
 contract RefundableCrowdsale is FinalizableCrowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  // minimum amount of funds to be raised in weis
-  uint256 public goal;
+    // minimum amount of funds to be raised in weis
+    uint256 private _goal;
 
-  // refund escrow used to hold funds while crowdsale is running
-  RefundEscrow private escrow;
+    // refund escrow used to hold funds while crowdsale is running
+    RefundEscrow private _escrow;
 
-  /**
-   * @dev Constructor, creates RefundEscrow.
-   * @param _goal Funding goal
-   */
-  constructor(uint256 _goal) public {
-    require(_goal > 0);
-    escrow = new RefundEscrow(wallet);
-    goal = _goal;
-  }
-
-  /**
-   * @dev Investors can claim refunds here if crowdsale is unsuccessful
-   */
-  function claimRefund() public {
-    require(isFinalized);
-    require(!goalReached());
-
-    escrow.withdraw(msg.sender);
-  }
-
-  /**
-   * @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 owner calls finalize()
-   */
-  function finalization() internal {
-    if (goalReached()) {
-      escrow.close();
-      escrow.beneficiaryWithdraw();
-    } else {
-      escrow.enableRefunds();
+    /**
+     * @dev Constructor, creates RefundEscrow.
+     * @param goal Funding goal
+     */
+    constructor (uint256 goal) public {
+        require(goal > 0);
+        _escrow = new RefundEscrow(wallet());
+        _goal = goal;
     }
 
-    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.
-   */
-  function _forwardFunds() internal {
-    escrow.deposit.value(msg.value)(msg.sender);
-  }
+    /**
+     * @dev Investors can claim refunds here if crowdsale is unsuccessful
+     * @param refundee Whose refund will be claimed.
+     */
+    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

@@ -1,50 +1,51 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Crowdsale.sol";
-import "../../token/ERC20/ERC20.sol";
-import "../../token/ERC20/ERC20Basic.sol";
+import "../../token/ERC20/IERC20.sol";
 import "../../token/ERC20/SafeERC20.sol";
 import "../../math/SafeMath.sol";
-
+import "../../math/Math.sol";
 
 /**
  * @title AllowanceCrowdsale
  * @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 SafeERC20 for ERC20;
+    using SafeMath for uint256;
+    using SafeERC20 for IERC20;
 
-  address public tokenWallet;
+    address private _tokenWallet;
 
-  /**
-   * @dev Constructor, takes token wallet address.
-   * @param _tokenWallet Address holding the tokens, which has approved allowance to the crowdsale
-   */
-  constructor(address _tokenWallet) public {
-    require(_tokenWallet != address(0));
-    tokenWallet = _tokenWallet;
-  }
+    /**
+     * @dev Constructor, takes token wallet address.
+     * @param tokenWallet Address holding the tokens, which has approved allowance to the crowdsale
+     */
+    constructor (address tokenWallet) public {
+        require(tokenWallet != address(0));
+        _tokenWallet = tokenWallet;
+    }
 
-  /**
-   * @dev Checks the amount of tokens left in the allowance.
-   * @return Amount of tokens left in the allowance
-   */
-  function remainingTokens() public view returns (uint256) {
-    return token.allowance(tokenWallet, this);
-  }
+    /**
+     * @return the address of the wallet that will hold the tokens.
+     */
+    function tokenWallet() public view returns (address) {
+        return _tokenWallet;
+    }
 
-  /**
-   * @dev Overrides parent behavior by transferring tokens from wallet.
-   * @param _beneficiary Token purchaser
-   * @param _tokenAmount Amount of tokens purchased
-   */
-  function _deliverTokens(
-    address _beneficiary,
-    uint256 _tokenAmount
-  )
-    internal
-  {
-    token.safeTransferFrom(tokenWallet, _beneficiary, _tokenAmount);
-  }
+    /**
+     * @dev Checks the amount of tokens left in the allowance.
+     * @return Amount of tokens left in the allowance
+     */
+    function remainingTokens() public view returns (uint256) {
+        return Math.min(token().balanceOf(_tokenWallet), token().allowance(_tokenWallet, address(this)));
+    }
+
+    /**
+     * @dev Overrides parent behavior by transferring tokens from wallet.
+     * @param beneficiary Token purchaser
+     * @param tokenAmount Amount of tokens purchased
+     */
+    function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
+        token().safeTransferFrom(_tokenWallet, beneficiary, tokenAmount);
+    }
 }

contracts/crowdsale/emission/MintedCrowdsale.sol

@@ -1,8 +1,7 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../Crowdsale.sol";
-import "../../token/ERC20/MintableToken.sol";
-
+import "../../token/ERC20/ERC20Mintable.sol";
 
 /**
  * @title MintedCrowdsale
@@ -10,19 +9,13 @@ import "../../token/ERC20/MintableToken.sol";
  * Token ownership should be transferred to MintedCrowdsale for minting.
  */
 contract MintedCrowdsale is Crowdsale {
-
-  /**
-   * @dev Overrides delivery by minting tokens upon purchase.
-   * @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.
-    require(MintableToken(address(token)).mint(_beneficiary, _tokenAmount));
-  }
+    /**
+     * @dev Overrides delivery by minting tokens upon purchase.
+     * @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.
+        require(ERC20Mintable(address(token())).mint(beneficiary, tokenAmount));
+    }
 }

contracts/crowdsale/price/IncreasingPriceCrowdsale.sol

@@ -1,9 +1,8 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../validation/TimedCrowdsale.sol";
 import "../../math/SafeMath.sol";
 
-
 /**
  * @title IncreasingPriceCrowdsale
  * @dev Extension of Crowdsale contract that increases the price of tokens linearly in time.
@@ -11,46 +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 public initialRate;
-  uint256 public finalRate;
+    uint256 private _initialRate;
+    uint256 private _finalRate;
 
-  /**
-   * @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 _finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
-   */
-  constructor(uint256 _initialRate, uint256 _finalRate) public {
-    require(_initialRate >= _finalRate);
-    require(_finalRate > 0);
-    initialRate = _initialRate;
-    finalRate = _finalRate;
-  }
+    /**
+     * @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 finalRate Number of tokens a buyer gets per wei at the end of the crowdsale
+     */
+    constructor (uint256 initialRate, uint256 finalRate) public {
+        require(finalRate > 0);
+        require(initialRate > finalRate);
+        _initialRate = initialRate;
+        _finalRate = 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) {
-    // solium-disable-next-line security/no-block-members
-    uint256 elapsedTime = block.timestamp.sub(openingTime);
-    uint256 timeRange = closingTime.sub(openingTime);
-    uint256 rateRange = initialRate.sub(finalRate);
-    return initialRate.sub(elapsedTime.mul(rateRange).div(timeRange));
-  }
+    /**
+     * 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();
+    }
 
-  /**
-   * @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);
-  }
+    /**
+     * @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;
+        }
+
+        // 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

@@ -1,48 +1,48 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
 
-
 /**
  * @title CappedCrowdsale
  * @dev Crowdsale with a limit for total contributions.
  */
 contract CappedCrowdsale is Crowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  uint256 public cap;
+    uint256 private _cap;
 
-  /**
-   * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
-   * @param _cap Max amount of wei to be contributed
-   */
-  constructor(uint256 _cap) public {
-    require(_cap > 0);
-    cap = _cap;
-  }
+    /**
+     * @dev Constructor, takes maximum amount of wei accepted in the crowdsale.
+     * @param cap Max amount of wei to be contributed
+     */
+    constructor (uint256 cap) public {
+        require(cap > 0);
+        _cap = cap;
+    }
 
-  /**
-   * @dev Checks whether the cap has been reached.
-   * @return Whether the cap was reached
-   */
-  function capReached() public view returns (bool) {
-    return weiRaised >= cap;
-  }
+    /**
+     * @return the cap of the crowdsale.
+     */
+    function cap() public view returns (uint256) {
+        return _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
-  {
-    super._preValidatePurchase(_beneficiary, _weiAmount);
-    require(weiRaised.add(_weiAmount) <= cap);
-  }
+    /**
+     * @dev Checks whether the cap has been reached.
+     * @return Whether the cap was reached
+     */
+    function capReached() public view returns (bool) {
+        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);
+    }
 }

contracts/crowdsale/validation/IndividuallyCappedCrowdsale.sol

@@ -1,94 +1,63 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
-import "../../ownership/Ownable.sol";
-
+import "../../access/roles/CapperRole.sol";
 
 /**
  * @title IndividuallyCappedCrowdsale
- * @dev Crowdsale with per-user caps.
+ * @dev Crowdsale with per-beneficiary caps.
  */
-contract IndividuallyCappedCrowdsale is Ownable, Crowdsale {
-  using SafeMath for uint256;
+contract IndividuallyCappedCrowdsale is Crowdsale, CapperRole {
+    using SafeMath for uint256;
 
-  mapping(address => uint256) public contributions;
-  mapping(address => uint256) public caps;
+    mapping(address => uint256) private _contributions;
+    mapping(address => uint256) private _caps;
 
-  /**
-   * @dev Sets a specific user's maximum contribution.
-   * @param _beneficiary Address to be capped
-   * @param _cap Wei limit for individual contribution
-   */
-  function setUserCap(address _beneficiary, uint256 _cap) external onlyOwner {
-    caps[_beneficiary] = _cap;
-  }
-
-  /**
-   * @dev Sets a group of users' maximum contribution.
-   * @param _beneficiaries List of addresses to be capped
-   * @param _cap Wei limit for individual contribution
-   */
-  function setGroupCap(
-    address[] _beneficiaries,
-    uint256 _cap
-  )
-    external
-    onlyOwner
-  {
-    for (uint256 i = 0; i < _beneficiaries.length; i++) {
-      caps[_beneficiaries[i]] = _cap;
+    /**
+     * @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 Returns the cap of a specific user.
-   * @param _beneficiary Address whose cap is to be checked
-   * @return Current cap for individual user
-   */
-  function getUserCap(address _beneficiary) public view returns (uint256) {
-    return caps[_beneficiary];
-  }
+    /**
+     * @dev Returns the cap of a specific beneficiary.
+     * @param beneficiary Address whose cap is to be checked
+     * @return Current cap for individual beneficiary
+     */
+    function getCap(address beneficiary) public view returns (uint256) {
+        return _caps[beneficiary];
+    }
 
-  /**
-   * @dev Returns the amount contributed so far by a sepecific user.
-   * @param _beneficiary Address of contributor
-   * @return User contribution so far
-   */
-  function getUserContribution(address _beneficiary)
-    public view returns (uint256)
-  {
-    return contributions[_beneficiary];
-  }
+    /**
+     * @dev Returns the amount contributed so far by a specific beneficiary.
+     * @param beneficiary Address of contributor
+     * @return Beneficiary contribution so far
+     */
+    function getContribution(address beneficiary) public view returns (uint256) {
+        return _contributions[beneficiary];
+    }
 
-  /**
-   * @dev Extend parent behavior requiring purchase to respect the user's funding cap.
-   * @param _beneficiary Token purchaser
-   * @param _weiAmount Amount of wei contributed
-   */
-  function _preValidatePurchase(
-    address _beneficiary,
-    uint256 _weiAmount
-  )
-    internal
-  {
-    super._preValidatePurchase(_beneficiary, _weiAmount);
-    require(contributions[_beneficiary].add(_weiAmount) <= caps[_beneficiary]);
-  }
-
-  /**
-   * @dev Extend parent behavior to update user 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 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);
+    }
 }

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

@@ -1,64 +1,77 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../../math/SafeMath.sol";
 import "../Crowdsale.sol";
 
-
 /**
  * @title TimedCrowdsale
  * @dev Crowdsale accepting contributions only within a time frame.
  */
 contract TimedCrowdsale is Crowdsale {
-  using SafeMath for uint256;
+    using SafeMath for uint256;
 
-  uint256 public openingTime;
-  uint256 public closingTime;
+    uint256 private _openingTime;
+    uint256 private _closingTime;
 
-  /**
-   * @dev Reverts if not in crowdsale time range.
-   */
-  modifier onlyWhileOpen {
-    // solium-disable-next-line security/no-block-members
-    require(block.timestamp >= openingTime && block.timestamp <= closingTime);
-    _;
-  }
+    /**
+     * @dev Reverts if not in crowdsale time range.
+     */
+    modifier onlyWhileOpen {
+        require(isOpen());
+        _;
+    }
 
-  /**
-   * @dev Constructor, takes crowdsale opening and closing times.
-   * @param _openingTime Crowdsale opening time
-   * @param _closingTime Crowdsale closing time
-   */
-  constructor(uint256 _openingTime, uint256 _closingTime) public {
-    // solium-disable-next-line security/no-block-members
-    require(_openingTime >= block.timestamp);
-    require(_closingTime >= _openingTime);
+    /**
+     * @dev Constructor, takes crowdsale opening and closing times.
+     * @param openingTime Crowdsale opening time
+     * @param closingTime Crowdsale closing time
+     */
+    constructor (uint256 openingTime, uint256 closingTime) public {
+        // solhint-disable-next-line not-rely-on-time
+        require(openingTime >= block.timestamp);
+        require(closingTime > openingTime);
 
-    openingTime = _openingTime;
-    closingTime = _closingTime;
-  }
+        _openingTime = openingTime;
+        _closingTime = closingTime;
+    }
 
-  /**
-   * @dev Checks whether the period in which the crowdsale is open has already elapsed.
-   * @return Whether crowdsale period has elapsed
-   */
-  function hasClosed() public view returns (bool) {
-    // solium-disable-next-line security/no-block-members
-    return block.timestamp > closingTime;
-  }
+    /**
+     * @return the crowdsale opening time.
+     */
+    function openingTime() public view returns (uint256) {
+        return _openingTime;
+    }
 
-  /**
-   * @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
-  {
-    super._preValidatePurchase(_beneficiary, _weiAmount);
-  }
+    /**
+     * @return the crowdsale closing time.
+     */
+    function closingTime() public view returns (uint256) {
+        return _closingTime;
+    }
 
+    /**
+     * @return true if the crowdsale is open, false otherwise.
+     */
+    function isOpen() public view returns (bool) {
+        // solhint-disable-next-line not-rely-on-time
+        return block.timestamp >= _openingTime && block.timestamp <= _closingTime;
+    }
+
+    /**
+     * @dev Checks whether the period in which the crowdsale is open has already elapsed.
+     * @return Whether crowdsale period has elapsed
+     */
+    function hasClosed() public view returns (bool) {
+        // solhint-disable-next-line not-rely-on-time
+        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);
+    }
 }

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/crowdsale/validation/WhitelistedCrowdsale.sol

@@ -1,27 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../Crowdsale.sol";
-import "../../access/Whitelist.sol";
-
-
-/**
- * @title WhitelistedCrowdsale
- * @dev Crowdsale in which only whitelisted users can contribute.
- */
-contract WhitelistedCrowdsale is Whitelist, Crowdsale {
-  /**
-   * @dev Extend parent behavior requiring beneficiary to be in whitelist.
-   * @param _beneficiary Token beneficiary
-   * @param _weiAmount Amount of wei contributed
-   */
-  function _preValidatePurchase(
-    address _beneficiary,
-    uint256 _weiAmount
-  )
-    internal
-    onlyIfWhitelisted(_beneficiary)
-  {
-    super._preValidatePurchase(_beneficiary, _weiAmount);
-  }
-
-}

contracts/cryptography/ECDSA.sol

@@ -0,0 +1,59 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title Elliptic curve signature operations
+ * @dev Based on https://gist.github.com/axic/5b33912c6f61ae6fd96d6c4a47afde6d
+ * TODO Remove this library once solidity supports passing a signature to ecrecover.
+ * See https://github.com/ethereum/solidity/issues/864
+ */
+
+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
+        if (signature.length != 65) {
+            return (address(0));
+        }
+
+        // Divide the signature in r, s and v variables
+        // ecrecover takes the signature parameters, and the only way to get them
+        // 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);
+        }
+    }
+
+    /**
+     * 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

@@ -0,0 +1,34 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title MerkleProof
+ * @dev Merkle proof verification based on
+ * 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
+     * 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 root Merkle root
+     * @param leaf Leaf of Merkle tree
+     */
+    function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) internal pure returns (bool) {
+        bytes32 computedHash = leaf;
+
+        for (uint256 i = 0; i < proof.length; i++) {
+            bytes32 proofElement = proof[i];
+
+            if (computedHash < proofElement) {
+                // Hash(current computed hash + current element of the proof)
+                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
+            } else {
+                // Hash(current element of the proof + current computed hash)
+                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
+            }
+        }
+
+        // Check if the computed hash (root) is equal to the provided root
+        return computedHash == root;
+    }
+}

contracts/drafts/Counter.sol

@@ -0,0 +1,24 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title Counter
+ * @author Matt Condon (@shrugs)
+ * @dev Provides an incrementing uint256 id acquired by the `Counter#next` getter.
+ * Use this for issuing ERC721 ids or keeping track of request ids, anything you want, really.
+ *
+ * Include with `using Counter for Counter.Counter;`
+ * @notice Does not allow an Id of 0, which is popularly used to signify a null state in solidity.
+ * Does not protect from overflows, but if you have 2^256 ids, you have other problems.
+ * (But actually, it's generally impossible to increment a counter this many times, energy wise
+ * so it's not something you have to worry about.)
+ */
+library Counter {
+    struct Counter {
+        uint256 current; // default: 0
+    }
+
+    function next(Counter storage index) internal returns (uint256) {
+        index.current += 1;
+        return index.current;
+    }
+}

contracts/drafts/ERC1046/TokenMetadata.sol

@@ -0,0 +1,24 @@
+pragma solidity ^0.5.0;
+
+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
+ */
+contract ERC20TokenMetadata is IERC20 {
+    function tokenURI() external view returns (string memory);
+}
+
+contract ERC20WithMetadata is ERC20TokenMetadata {
+    string private _tokenURI;
+
+    constructor (string memory tokenURI) public {
+        _tokenURI = tokenURI;
+    }
+
+    function tokenURI() external view returns (string memory) {
+        return _tokenURI;
+    }
+}

contracts/drafts/ERC20Migrator.sol

@@ -0,0 +1,100 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC20/IERC20.sol";
+import "../token/ERC20/ERC20Mintable.sol";
+import "../token/ERC20/SafeERC20.sol";
+import "../math/Math.sol";
+
+/**
+ * @title ERC20Migrator
+ * @dev This contract can be used to migrate an ERC20 token from one
+ * contract to another, where each token holder has to opt-in to the migration.
+ * To opt-in, users must approve for this contract the number of tokens they
+ * want to migrate. Once the allowance is set up, anyone can trigger the
+ * migration to the new token contract. In this way, token holders "turn in"
+ * their old balance and will be minted an equal amount in the new token.
+ * The new token contract must be mintable. For the precise interface refer to
+ * OpenZeppelin's ERC20Mintable, but the only functions that are needed are
+ * `isMinter(address)` and `mint(address, amount)`. The migrator will check
+ * that it is a minter for the token.
+ * The balance from the legacy token will be transfered to the migrator, as it
+ * is migrated, and remain there forever.
+ * Although this contract can be used in many different scenarios, the main
+ * motivation was to provide a way to migrate ERC20 tokens into an upgradeable
+ * version of it using ZeppelinOS. To read more about how this can be done
+ * using this implementation, please follow the official documentation site of
+ * ZeppelinOS: https://docs.zeppelinos.org/docs/erc20_onboarding.html
+ * Example of usage:
+ * ```
+ * const migrator = await ERC20Migrator.new(legacyToken.address);
+ * await newToken.addMinter(migrator.address);
+ * await migrator.beginMigration(newToken.address);
+ * ```
+ */
+contract ERC20Migrator {
+    using SafeERC20 for IERC20;
+
+    /// Address of the old token contract
+    IERC20 private _legacyToken;
+
+    /// Address of the new token contract
+    ERC20Mintable private _newToken;
+
+    /**
+     * @param legacyToken address of the old token contract
+     */
+    constructor (IERC20 legacyToken) public {
+        require(address(legacyToken) != address(0));
+        _legacyToken = legacyToken;
+    }
+
+    /**
+     * @dev Returns the legacy token that is being migrated.
+     */
+    function legacyToken() public view returns (IERC20) {
+        return _legacyToken;
+    }
+
+    /**
+     * @dev Returns the new token to which we are migrating.
+     */
+    function newToken() public view returns (IERC20) {
+        return _newToken;
+    }
+
+    /**
+     * @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.
+     * @param newToken the token that will be minted
+     */
+    function beginMigration(ERC20Mintable newToken) public {
+        require(address(_newToken) == address(0));
+        require(address(newToken) != address(0));
+        require(newToken.isMinter(address(this)));
+
+        _newToken = newToken;
+    }
+
+    /**
+     * @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.
+     * @param account whose tokens will be migrated
+     * @param amount amount of tokens to be migrated
+     */
+    function migrate(address account, uint256 amount) public {
+        _legacyToken.safeTransferFrom(account, address(this), amount);
+        _newToken.mint(account, amount);
+    }
+
+    /**
+     * @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.
+     * @param account whose tokens will be migrated
+     */
+    function migrateAll(address account) public {
+        uint256 balance = _legacyToken.balanceOf(account);
+        uint256 allowance = _legacyToken.allowance(account, address(this));
+        uint256 amount = Math.min(balance, allowance);
+        migrate(account, amount);
+    }
+}

contracts/drafts/SignatureBouncer.sol

@@ -0,0 +1,120 @@
+pragma solidity ^0.5.0;
+
+import "../access/roles/SignerRole.sol";
+import "../cryptography/ECDSA.sol";
+
+/**
+ * @title SignatureBouncer
+ * @author PhABC, Shrugs and aflesher
+ * @dev SignatureBouncer allows users to submit a signature as a permission to
+ * do an action.
+ * If the signature is from one of the authorized signer addresses, the
+ * signature is valid.
+ * Note that SignatureBouncer offers no protection against replay attacks, users
+ * must add this themselves!
+ *
+ * Signer addresses can be individual servers signing grants or different
+ * users within a decentralized club that have permission to invite other
+ * members. This technique is useful for whitelists and airdrops; instead of
+ * putting all valid addresses on-chain, simply sign a grant of the form
+ * keccak256(abi.encodePacked(`:contractAddress` + `:granteeAddress`)) using a
+ * valid signer address.
+ * Then restrict access to your crowdsale/whitelist/airdrop using the
+ * `onlyValidSignature` modifier (or implement your own using _isValidSignature).
+ * In addition to `onlyValidSignature`, `onlyValidSignatureAndMethod` and
+ * `onlyValidSignatureAndData` can be used to restrict access to only a given
+ * method or a given method with given parameters respectively.
+ * See the tests in SignatureBouncer.test.js for specific usage examples.
+ *
+ * @notice A method that uses the `onlyValidSignatureAndData` modifier must make
+ * the _signature parameter the "last" parameter. You cannot sign a message that
+ * has its own signature in it so the last 128 bytes of msg.data (which
+ * represents the length of the _signature data and the _signaature data itself)
+ * is ignored when validating. Also non fixed sized parameters make constructing
+ * the data in the signature much more complex.
+ * See https://ethereum.stackexchange.com/a/50616 for more details.
+ */
+contract SignatureBouncer is SignerRole {
+    using ECDSA for bytes32;
+
+    // Function selectors are 4 bytes long, as documented in
+    // https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector
+    uint256 private constant _METHOD_ID_SIZE = 4;
+    // Signature size is 65 bytes (tightly packed v + r + s), but gets padded to 96 bytes
+    uint256 private constant _SIGNATURE_SIZE = 96;
+
+    constructor () internal {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    /**
+     * @dev requires that a valid signature of a signer was provided
+     */
+    modifier onlyValidSignature(bytes memory signature) {
+        require(_isValidSignature(msg.sender, signature));
+        _;
+    }
+
+    /**
+     * @dev requires that a valid signature with a specifed method of a signer was provided
+     */
+    modifier onlyValidSignatureAndMethod(bytes memory 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 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

@@ -0,0 +1,172 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC20/SafeERC20.sol";
+import "../ownership/Ownable.sol";
+import "../math/SafeMath.sol";
+
+/**
+ * @title TokenVesting
+ * @dev A token holder contract that can release its token balance gradually like a
+ * typical vesting scheme, with a cliff and vesting period. Optionally revocable by the
+ * owner.
+ */
+contract TokenVesting is Ownable {
+    // The vesting schedule is time-based (i.e. using block timestamps as opposed to e.g. block numbers), and is
+    // 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
+
+    using SafeMath for uint256;
+    using SafeERC20 for IERC20;
+
+    event TokensReleased(address token, uint256 amount);
+    event TokenVestingRevoked(address token);
+
+    // beneficiary of tokens after they are released
+    address private _beneficiary;
+
+    // Durations and timestamps are expressed in UNIX time, the same units as block.timestamp.
+    uint256 private _cliff;
+    uint256 private _start;
+    uint256 private _duration;
+
+    bool private _revocable;
+
+    mapping (address => uint256) private _released;
+    mapping (address => bool) private _revoked;
+
+    /**
+     * @dev Creates a vesting contract that vests its balance of any ERC20 token to the
+     * 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;
+        _duration = duration;
+        _cliff = start.add(cliffDuration);
+        _start = start;
+    }
+
+    /**
+     * @return the beneficiary of the tokens.
+     */
+    function beneficiary() public view returns (address) {
+        return _beneficiary;
+    }
+
+    /**
+     * @return the cliff time of the token vesting.
+     */
+    function cliff() public view returns (uint256) {
+        return _cliff;
+    }
+
+    /**
+     * @return the start time of the token vesting.
+     */
+    function start() public view returns (uint256) {
+        return _start;
+    }
+
+    /**
+     * @return the duration of the token vesting.
+     */
+    function duration() public view returns (uint256) {
+        return _duration;
+    }
+
+    /**
+     * @return true if the vesting is revocable.
+     */
+    function revocable() public view returns (bool) {
+        return _revocable;
+    }
+
+    /**
+     * @return the amount of the token released.
+     */
+    function released(address token) public view returns (uint256) {
+        return _released[token];
+    }
+
+    /**
+     * @return true if the token is revoked.
+     */
+    function revoked(address token) public view returns (bool) {
+        return _revoked[token];
+    }
+
+    /**
+     * @notice Transfers vested tokens to beneficiary.
+     * @param token ERC20 token which is being vested
+     */
+    function release(IERC20 token) public {
+        uint256 unreleased = _releasableAmount(token);
+
+        require(unreleased > 0);
+
+        _released[address(token)] = _released[address(token)].add(unreleased);
+
+        token.safeTransfer(_beneficiary, unreleased);
+
+        emit TokensReleased(address(token), unreleased);
+    }
+
+    /**
+     * @notice Allows the owner to revoke the vesting. Tokens already vested
+     * remain in the contract, the rest are returned to the owner.
+     * @param token ERC20 token which is being vested
+     */
+    function revoke(IERC20 token) public onlyOwner {
+        require(_revocable);
+        require(!_revoked[address(token)]);
+
+        uint256 balance = token.balanceOf(address(this));
+
+        uint256 unreleased = _releasableAmount(token);
+        uint256 refund = balance.sub(unreleased);
+
+        _revoked[address(token)] = true;
+
+        token.safeTransfer(owner(), refund);
+
+        emit TokenVestingRevoked(address(token));
+    }
+
+    /**
+     * @dev Calculates the amount that has already vested but hasn't been released yet.
+     * @param token ERC20 token which is being vested
+     */
+    function _releasableAmount(IERC20 token) private view returns (uint256) {
+        return _vestedAmount(token).sub(_released[address(token)]);
+    }
+
+    /**
+     * @dev Calculates the amount that has already vested.
+     * @param token ERC20 token which is being vested
+     */
+    function _vestedAmount(IERC20 token) private view returns (uint256) {
+        uint256 currentBalance = token.balanceOf(address(this));
+        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/RBACWithAdmin.sol

@@ -1,66 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../access/rbac/RBAC.sol";
-
-
-/**
- * @title RBACWithAdmin
- * @author Matt Condon (@Shrugs)
- * @dev It's recommended that you define constants in the contract,
- * like ROLE_ADMIN below, to avoid typos.
- * @notice RBACWithAdmin is probably too expansive and powerful for your
- * application; an admin is actually able to change any address to any role
- * which is a very large API surface. It's recommended that you follow a strategy
- * of strictly defining the abilities of your roles
- * and the API-surface of your contract.
- * This is just an example for example's sake.
- */
-contract RBACWithAdmin is RBAC {
-  /**
-   * A constant role name for indicating admins.
-   */
-  string public constant ROLE_ADMIN = "admin";
-
-  /**
-   * @dev modifier to scope access to admins
-   * // reverts
-   */
-  modifier onlyAdmin()
-  {
-    checkRole(msg.sender, ROLE_ADMIN);
-    _;
-  }
-
-  /**
-   * @dev constructor. Sets msg.sender as admin by default
-   */
-  constructor()
-    public
-  {
-    addRole(msg.sender, ROLE_ADMIN);
-  }
-
-  /**
-   * @dev add a role to an address
-   * @param _addr address
-   * @param _roleName the name of the role
-   */
-  function adminAddRole(address _addr, string _roleName)
-    public
-    onlyAdmin
-  {
-    addRole(_addr, _roleName);
-  }
-
-  /**
-   * @dev remove a role from an address
-   * @param _addr address
-   * @param _roleName the name of the role
-   */
-  function adminRemoveRole(address _addr, string _roleName)
-    public
-    onlyAdmin
-  {
-    removeRole(_addr, _roleName);
-  }
-}

contracts/examples/SampleCrowdsale.sol

@@ -1,25 +1,22 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
 import "../crowdsale/validation/CappedCrowdsale.sol";
 import "../crowdsale/distribution/RefundableCrowdsale.sol";
 import "../crowdsale/emission/MintedCrowdsale.sol";
-import "../token/ERC20/MintableToken.sol";
-
+import "../token/ERC20/ERC20Mintable.sol";
+import "../token/ERC20/ERC20Detailed.sol";
 
 /**
  * @title SampleCrowdsaleToken
  * @dev Very simple ERC20 Token that can be minted.
  * It is meant to be used in a crowdsale contract.
  */
-contract SampleCrowdsaleToken is MintableToken {
-
-  string public constant name = "Sample Crowdsale Token";
-  string public constant symbol = "SCT";
-  uint8 public constant decimals = 18;
-
+contract SampleCrowdsaleToken is ERC20Mintable, ERC20Detailed {
+    constructor () public ERC20Detailed("Sample Crowdsale Token", "SCT", 18) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }
 
-
 /**
  * @title SampleCrowdsale
  * @dev This is an example of a fully fledged crowdsale.
@@ -27,34 +24,30 @@ contract SampleCrowdsaleToken is MintableToken {
  * In this example we are providing following extensions:
  * CappedCrowdsale - sets a max boundary for raised funds
  * RefundableCrowdsale - set a min goal to be reached and returns funds if it's not met
+ * MintedCrowdsale - assumes the token can be minted by the crowdsale, which does so
+ * when receiving purchases.
  *
  * 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(
-    uint256 _openingTime,
-    uint256 _closingTime,
-    uint256 _rate,
-    address _wallet,
-    uint256 _cap,
-    MintableToken _token,
-    uint256 _goal
-  )
-    public
-    Crowdsale(_rate, _wallet, _token)
-    CappedCrowdsale(_cap)
-    TimedCrowdsale(_openingTime, _closingTime)
-    RefundableCrowdsale(_goal)
-  {
-    //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
-    require(_goal <= _cap);
-  }
+    constructor (
+        uint256 openingTime,
+        uint256 closingTime,
+        uint256 rate,
+        address payable wallet,
+        uint256 cap,
+        ERC20Mintable token,
+        uint256 goal
+    )
+        public
+        Crowdsale(rate, wallet, token)
+        CappedCrowdsale(cap)
+        TimedCrowdsale(openingTime, closingTime)
+        RefundableCrowdsale(goal)
+    {
+        //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
+        require(goal <= cap);
+    }
 }

contracts/examples/SimpleSavingsWallet.sol

@@ -1,40 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../ownership/Heritable.sol";
-
-
-/**
- * @title SimpleSavingsWallet
- * @dev Simplest form of savings wallet whose ownership can be claimed by a heir
- * if owner dies.
- * In this example, we take a very simple savings wallet providing two operations
- * (to send and receive funds) and extend its capabilities by making it Heritable.
- * The account that creates the contract is set as owner, who has the authority to
- * choose an heir account. Heir account can reclaim the contract ownership in the
- * case that the owner dies.
- */
-contract SimpleSavingsWallet is Heritable {
-
-  event Sent(address indexed payee, uint256 amount, uint256 balance);
-  event Received(address indexed payer, uint256 amount, uint256 balance);
-
-
-  constructor(uint256 _heartbeatTimeout) Heritable(_heartbeatTimeout) public {}
-
-  /**
-   * @dev wallet can receive funds.
-   */
-  function () external payable {
-    emit Received(msg.sender, msg.value, address(this).balance);
-  }
-
-  /**
-   * @dev wallet can send funds
-   */
-  function sendTo(address _payee, uint256 _amount) public onlyOwner {
-    require(_payee != address(0) && _payee != address(this));
-    require(_amount > 0);
-    _payee.transfer(_amount);
-    emit Sent(_payee, _amount, address(this).balance);
-  }
-}

contracts/examples/SimpleToken.sol

@@ -1,30 +1,22 @@
-pragma solidity ^0.4.24;
-
-
-import "../token/ERC20/StandardToken.sol";
+pragma solidity ^0.5.0;
 
+import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/ERC20Detailed.sol";
 
 /**
  * @title SimpleToken
  * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
  * Note they can later distribute these tokens as they wish using `transfer` and other
- * `StandardToken` functions.
+ * `ERC20` functions.
  */
-contract SimpleToken is StandardToken {
-
-  string public constant name = "SimpleToken";
-  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 {
-    totalSupply_ = INITIAL_SUPPLY;
-    balances[msg.sender] = INITIAL_SUPPLY;
-    emit Transfer(address(0), msg.sender, INITIAL_SUPPLY);
-  }
+contract SimpleToken is ERC20, ERC20Detailed {
+    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 ERC20Detailed("SimpleToken", "SIM", DECIMALS) {
+        _mint(msg.sender, INITIAL_SUPPLY);
+    }
 }

contracts/introspection/ERC165.sol

@@ -1,20 +1,44 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
+import "./IERC165.sol";
 
 /**
  * @title ERC165
- * @dev https://github.com/ethereum/EIPs/blob/master/EIPS/eip-165.md
+ * @author Matt Condon (@shrugs)
+ * @dev Implements ERC165 using a lookup table.
  */
-interface ERC165 {
+contract ERC165 is IERC165 {
+    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
+    /**
+     * 0x01ffc9a7 ===
+     *     bytes4(keccak256('supportsInterface(bytes4)'))
+     */
 
-  /**
-   * @notice Query if a contract implements an interface
-   * @param _interfaceId The interface identifier, as specified in ERC-165
-   * @dev Interface identification is specified in ERC-165. This function
-   * uses less than 30,000 gas.
-   */
-  function supportsInterface(bytes4 _interfaceId)
-    external
-    view
-    returns (bool);
+    /**
+     * @dev a mapping of interface id to whether or not it's supported
+     */
+    mapping(bytes4 => bool) private _supportedInterfaces;
+
+    /**
+     * @dev A contract implementing SupportsInterfaceWithLookup
+     * implement ERC165 itself
+     */
+    constructor () internal {
+        _registerInterface(_INTERFACE_ID_ERC165);
+    }
+
+    /**
+     * @dev implement supportsInterface(bytes4) using a lookup table
+     */
+    function supportsInterface(bytes4 interfaceId) external view 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

@@ -0,0 +1,123 @@
+pragma solidity ^0.5.0;
+
+/**
+ * @title ERC165Checker
+ * @dev Use `using ERC165Checker for address`; to include this library
+ * 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
+    bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;
+
+    bytes4 private constant _INTERFACE_ID_ERC165 = 0x01ffc9a7;
+    /**
+     * 0x01ffc9a7 ===
+     *     bytes4(keccak256('supportsInterface(bytes4)'))
+     */
+
+    /**
+     * @notice Query if a contract supports ERC165
+     * @param account The address of the contract to query for support of ERC165
+     * @return true if the contract at account implements ERC165
+     */
+    function _supportsERC165(address account) internal view returns (bool) {
+        // Any contract that implements ERC165 must explicitly indicate support of
+        // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
+        return _supportsERC165Interface(account, _INTERFACE_ID_ERC165) &&
+            !_supportsERC165Interface(account, _INTERFACE_ID_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[] memory 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++) {
+            if (!_supportsERC165Interface(account, interfaceIds[i])) {
+                return false;
+            }
+        }
+
+        // all interfaces supported
+        return true;
+    }
+
+    /**
+     * @notice Query if a contract implements an interface, does not check ERC165 support
+     * @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 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);
+    }
+
+    /**
+     * @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
+     * @param interfaceId The interface identifier, as specified in ERC-165
+     * @return success true if the STATICCALL succeeded, false otherwise
+     * @return result true if the STATICCALL succeeded and the contract at account
+     * indicates support of the interface with identifier interfaceId, false otherwise
+     */
+    function _callERC165SupportsInterface(address account, bytes4 interfaceId)
+        private
+        view
+        returns (bool success, bool result)
+    {
+        bytes memory encodedParams = abi.encodeWithSelector(_INTERFACE_ID_ERC165, interfaceId);
+
+        // solhint-disable-next-line no-inline-assembly
+        assembly {
+            let encodedParams_data := add(0x20, encodedParams)
+            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

@@ -0,0 +1,15 @@
+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
+     * @param interfaceId The interface identifier, as specified in ERC-165
+     * @dev Interface identification is specified in ERC-165. This function
+     * uses less than 30,000 gas.
+     */
+    function supportsInterface(bytes4 interfaceId) external view returns (bool);
+}

contracts/introspection/SupportsInterfaceWithLookup.sol

@@ -1,54 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "./ERC165.sol";
-
-
-/**
- * @title SupportsInterfaceWithLookup
- * @author Matt Condon (@shrugs)
- * @dev Implements ERC165 using a lookup table.
- */
-contract SupportsInterfaceWithLookup is ERC165 {
-
-  bytes4 public constant InterfaceId_ERC165 = 0x01ffc9a7;
-  /**
-   * 0x01ffc9a7 ===
-   *   bytes4(keccak256('supportsInterface(bytes4)'))
-   */
-
-  /**
-   * @dev a mapping of interface id to whether or not it's supported
-   */
-  mapping(bytes4 => bool) internal supportedInterfaces;
-
-  /**
-   * @dev A contract implementing SupportsInterfaceWithLookup
-   * implement ERC165 itself
-   */
-  constructor()
-    public
-  {
-    _registerInterface(InterfaceId_ERC165);
-  }
-
-  /**
-   * @dev implement supportsInterface(bytes4) using a lookup table
-   */
-  function supportsInterface(bytes4 _interfaceId)
-    external
-    view
-    returns (bool)
-  {
-    return supportedInterfaces[_interfaceId];
-  }
-
-  /**
-   * @dev private method for registering an interface
-   */
-  function _registerInterface(bytes4 _interfaceId)
-    internal
-  {
-    require(_interfaceId != 0xffffffff);
-    supportedInterfaces[_interfaceId] = true;
-  }
-}

contracts/lifecycle/Destructible.sol

@@ -1,22 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "../ownership/Ownable.sol";
-
-
-/**
- * @title Destructible
- * @dev Base contract that can be destroyed by owner. All funds in contract will be sent to the owner.
- */
-contract Destructible is Ownable {
-  /**
-   * @dev Transfers the current balance to the owner and terminates the contract.
-   */
-  function destroy() public onlyOwner {
-    selfdestruct(owner);
-  }
-
-  function destroyAndSend(address _recipient) public onlyOwner {
-    selfdestruct(_recipient);
-  }
-}

contracts/lifecycle/Pausable.sol

@@ -1,49 +1,57 @@
-pragma solidity ^0.4.24;
-
-
-import "../ownership/Ownable.sol";
+pragma solidity ^0.5.0;
 
+import "../access/roles/PauserRole.sol";
 
 /**
  * @title Pausable
  * @dev Base contract which allows children to implement an emergency stop mechanism.
  */
-contract Pausable is Ownable {
-  event Pause();
-  event Unpause();
+contract Pausable is PauserRole {
+    event Paused(address account);
+    event Unpaused(address account);
 
-  bool public paused = false;
+    bool private _paused;
 
+    constructor () internal {
+        _paused = false;
+    }
 
-  /**
-   * @dev Modifier to make a function callable only when the contract is not paused.
-   */
-  modifier whenNotPaused() {
-    require(!paused);
-    _;
-  }
+    /**
+     * @return true if the contract is paused, false otherwise.
+     */
+    function paused() public view returns (bool) {
+        return _paused;
+    }
 
-  /**
-   * @dev Modifier to make a function callable only when the contract is paused.
-   */
-  modifier whenPaused() {
-    require(paused);
-    _;
-  }
+    /**
+     * @dev Modifier to make a function callable only when the contract is not paused.
+     */
+    modifier whenNotPaused() {
+        require(!_paused);
+        _;
+    }
 
-  /**
-   * @dev called by the owner to pause, triggers stopped state
-   */
-  function pause() public onlyOwner whenNotPaused {
-    paused = true;
-    emit Pause();
-  }
+    /**
+     * @dev Modifier to make a function callable only when the contract is paused.
+     */
+    modifier whenPaused() {
+        require(_paused);
+        _;
+    }
 
-  /**
-   * @dev called by the owner to unpause, returns to normal state
-   */
-  function unpause() public onlyOwner whenPaused {
-    paused = false;
-    emit Unpause();
-  }
+    /**
+     * @dev called by the owner to pause, triggers stopped state
+     */
+    function pause() public onlyPauser whenNotPaused {
+        _paused = true;
+        emit Paused(msg.sender);
+    }
+
+    /**
+     * @dev called by the owner to unpause, returns to normal state
+     */
+    function unpause() public onlyPauser whenPaused {
+        _paused = false;
+        emit Unpaused(msg.sender);
+    }
 }

contracts/lifecycle/TokenDestructible.sol

@@ -1,36 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../ownership/Ownable.sol";
-import "../token/ERC20/ERC20Basic.sol";
-
-
-/**
- * @title TokenDestructible:
- * @author Remco Bloemen <remco@2π.com>
- * @dev Base contract that can be destroyed by owner. All funds in contract including
- * listed tokens will be sent to the owner.
- */
-contract TokenDestructible is Ownable {
-
-  constructor() public payable { }
-
-  /**
-   * @notice Terminate contract and refund to owner
-   * @param _tokens List of addresses of ERC20 or ERC20Basic token contracts to
-   refund.
-   * @notice The called token contracts could try to re-enter this contract. Only
-   supply token contracts you trust.
-   */
-  function destroy(address[] _tokens) public onlyOwner {
-
-    // Transfer tokens to owner
-    for (uint256 i = 0; i < _tokens.length; i++) {
-      ERC20Basic token = ERC20Basic(_tokens[i]);
-      uint256 balance = token.balanceOf(this);
-      token.transfer(owner, balance);
-    }
-
-    // Transfer Eth to owner and terminate contract
-    selfdestruct(owner);
-  }
-}

contracts/math/Math.sol

@@ -1,24 +1,31 @@
-pragma solidity ^0.4.24;
-
+pragma solidity ^0.5.0;
 
 /**
  * @title Math
  * @dev Assorted math operations
  */
 library Math {
-  function max64(uint64 _a, uint64 _b) internal pure returns (uint64) {
-    return _a >= _b ? _a : _b;
-  }
+    /**
+    * @dev Returns the largest of two numbers.
+    */
+    function max(uint256 a, uint256 b) internal pure returns (uint256) {
+        return a >= b ? a : b;
+    }
 
-  function min64(uint64 _a, uint64 _b) internal pure returns (uint64) {
-    return _a < _b ? _a : _b;
-  }
+    /**
+    * @dev Returns the smallest of two numbers.
+    */
+    function min(uint256 a, uint256 b) internal pure returns (uint256) {
+        return a < b ? a : b;
+    }
 
-  function max256(uint256 _a, uint256 _b) internal pure returns (uint256) {
-    return _a >= _b ? _a : _b;
-  }
-
-  function min256(uint256 _a, uint256 _b) internal pure returns (uint256) {
-    return _a < _b ? _a : _b;
-  }
+    /**
+    * @dev Calculates the average of two numbers. Since these are integers,
+    * averages of an even and odd number cannot be represented, and will be
+    * rounded down.
+    */
+    function average(uint256 a, uint256 b) internal pure returns (uint256) {
+        // (a + b) / 2 can overflow, so we distribute
+        return (a / 2) + (b / 2) + ((a % 2 + b % 2) / 2);
+    }
 }

contracts/math/SafeMath.sol

@@ -1,52 +1,65 @@
-pragma solidity ^0.4.24;
-
+pragma solidity ^0.5.0;
 
 /**
  * @title SafeMath
- * @dev Math operations with safety checks that throw 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;
+        }
 
-  /**
-  * @dev Multiplies two numbers, throws on overflow.
-  */
-  function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
-    // Gas optimization: this is cheaper than asserting '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);
+
+        return c;
     }
 
-    c = _a * _b;
-    assert(c / _a == _b);
-    return c;
-  }
+    /**
+    * @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
 
-  /**
-  * @dev Integer division of two numbers, truncating the quotient.
-  */
-  function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
-    // assert(_b > 0); // Solidity automatically throws when dividing by 0
-    // uint256 c = _a / _b;
-    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
-    return _a / _b;
-  }
+        return c;
+    }
 
-  /**
-  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
-  */
-  function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
-    assert(_b <= _a);
-    return _a - _b;
-  }
+    /**
+    * @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
+    */
+    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
+        require(b <= a);
+        uint256 c = a - b;
 
-  /**
-  * @dev Adds two numbers, throws on overflow.
-  */
-  function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
-    c = _a + _b;
-    assert(c >= _a);
-    return c;
-  }
+        return c;
+    }
+
+    /**
+    * @dev Adds two unsigned integers, reverts on overflow.
+    */
+    function add(uint256 a, uint256 b) internal pure returns (uint256) {
+        uint256 c = a + b;
+        require(c >= a);
+
+        return c;
+    }
+
+    /**
+    * @dev Divides two unsigned integers 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

@@ -0,0 +1,9 @@
+pragma solidity ^0.5.0;
+
+import "../utils/Address.sol";
+
+contract AddressImpl {
+    function isContract(address account) external view returns (bool) {
+        return Address.isContract(account);
+    }
+}

contracts/mocks/AllowanceCrowdsaleImpl.sol

@@ -1,21 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/IERC20.sol";
 import "../crowdsale/emission/AllowanceCrowdsale.sol";
 
-
 contract AllowanceCrowdsaleImpl is AllowanceCrowdsale {
-
-  constructor (
-    uint256 _rate,
-    address _wallet,
-    ERC20 _token,
-    address _tokenWallet
-  )
-    public
-    Crowdsale(_rate, _wallet, _token)
-    AllowanceCrowdsale(_tokenWallet)
-  {
-  }
-
+    constructor (uint256 rate, address payable wallet, IERC20 token, address tokenWallet)
+        public
+        Crowdsale(rate, wallet, token)
+        AllowanceCrowdsale(tokenWallet)
+    {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/mocks/ArraysImpl.sol

@@ -0,0 +1,17 @@
+pragma solidity ^0.5.0;
+
+import "../utils/Arrays.sol";
+
+contract ArraysImpl {
+    using Arrays for uint256[];
+
+    uint256[] private array;
+
+    constructor (uint256[] memory _array) public {
+        array = _array;
+    }
+
+    function findUpperBound(uint256 _element) external view returns (uint256) {
+        return array.findUpperBound(_element);
+    }
+}

contracts/mocks/AutoIncrementingImpl.sol

@@ -1,21 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../AutoIncrementing.sol";
-
-
-contract AutoIncrementingImpl {
-  using AutoIncrementing for AutoIncrementing.Counter;
-
-  uint256 public theId;
-
-  // use whatever key you want to track your counters
-  mapping(string => AutoIncrementing.Counter) private counters;
-
-  function doThing(string _key)
-    public
-    returns (uint256)
-  {
-    theId = counters[_key].nextId();
-    return theId;
-  }
-}

contracts/mocks/BasicTokenMock.sol

@@ -1,15 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "../token/ERC20/BasicToken.sol";
-
-
-// mock class using BasicToken
-contract BasicTokenMock is BasicToken {
-
-  constructor(address _initialAccount, uint256 _initialBalance) public {
-    balances[_initialAccount] = _initialBalance;
-    totalSupply_ = _initialBalance;
-  }
-
-}

contracts/mocks/BouncerMock.sol

@@ -1,66 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../access/SignatureBouncer.sol";
-
-
-contract SignatureBouncerMock is SignatureBouncer {
-  function checkValidSignature(address _address, bytes _sig)
-    public
-    view
-    returns (bool)
-  {
-    return isValidSignature(_address, _sig);
-  }
-
-  function onlyWithValidSignature(bytes _sig)
-    public
-    onlyValidSignature(_sig)
-    view
-  {
-
-  }
-
-  function checkValidSignatureAndMethod(address _address, bytes _sig)
-    public
-    view
-    returns (bool)
-  {
-    return isValidSignatureAndMethod(_address, _sig);
-  }
-
-  function onlyWithValidSignatureAndMethod(bytes _sig)
-    public
-    onlyValidSignatureAndMethod(_sig)
-    view
-  {
-
-  }
-
-  function checkValidSignatureAndData(
-    address _address,
-    bytes,
-    uint,
-    bytes _sig
-  )
-    public
-    view
-    returns (bool)
-  {
-    return isValidSignatureAndData(_address, _sig);
-  }
-
-  function onlyWithValidSignatureAndData(uint, bytes _sig)
-    public
-    onlyValidSignatureAndData(_sig)
-    view
-  {
-
-  }
-
-  function theWrongMethod(bytes)
-    public
-    pure
-  {
-
-  }
-}

contracts/mocks/BurnableTokenMock.sol

@@ -1,13 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../token/ERC20/BurnableToken.sol";
-
-
-contract BurnableTokenMock is BurnableToken {
-
-  constructor(address _initialAccount, uint _initialBalance) public {
-    balances[_initialAccount] = _initialBalance;
-    totalSupply_ = _initialBalance;
-  }
-
-}

contracts/mocks/CappedCrowdsaleImpl.sol

@@ -1,21 +1,14 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/IERC20.sol";
 import "../crowdsale/validation/CappedCrowdsale.sol";
 
-
 contract CappedCrowdsaleImpl is CappedCrowdsale {
-
-  constructor (
-    uint256 _rate,
-    address _wallet,
-    ERC20 _token,
-    uint256 _cap
-  )
-    public
-    Crowdsale(_rate, _wallet, _token)
-    CappedCrowdsale(_cap)
-  {
-  }
-
+    constructor (uint256 rate, address payable wallet, IERC20 token, uint256 cap)
+        public
+        Crowdsale(rate, wallet, token)
+        CappedCrowdsale(cap)
+    {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/mocks/CapperRoleMock.sol

@@ -0,0 +1,18 @@
+pragma solidity ^0.5.0;
+
+import "../access/roles/CapperRole.sol";
+
+contract CapperRoleMock is CapperRole {
+    function removeCapper(address account) public {
+        _removeCapper(account);
+    }
+
+    function onlyCapperMock() public view onlyCapper {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    // Causes a compilation error if super._removeCapper is not internal
+    function _removeCapper(address account) internal {
+        super._removeCapper(account);
+    }
+}

contracts/mocks/ConditionalEscrowMock.sol

@@ -1,18 +1,16 @@
-pragma solidity ^0.4.24;
-
-
-import "../payment/ConditionalEscrow.sol";
+pragma solidity ^0.5.0;
 
+import "../payment/escrow/ConditionalEscrow.sol";
 
 // mock class using ConditionalEscrow
 contract ConditionalEscrowMock is ConditionalEscrow {
-  mapping(address => bool) public allowed;
+    mapping(address => bool) private _allowed;
 
-  function setAllowed(address _payee, bool _allowed) public {
-    allowed[_payee] = _allowed;
-  }
+    function setAllowed(address payee, bool allowed) public {
+        _allowed[payee] = allowed;
+    }
 
-  function withdrawalAllowed(address _payee) public view returns (bool) {
-    return allowed[_payee];
-  }
+    function withdrawalAllowed(address payee) public view returns (bool) {
+        return _allowed[payee];
+    }
 }

contracts/mocks/CounterImpl.sol

@@ -0,0 +1,17 @@
+pragma solidity ^0.5.0;
+
+import "../drafts/Counter.sol";
+
+contract CounterImpl {
+    using Counter for Counter.Counter;
+
+    uint256 public theId;
+
+    // use whatever key you want to track your counters
+    mapping(string => Counter.Counter) private _counters;
+
+    function doThing(string memory key) public returns (uint256) {
+        theId = _counters[key].next();
+        return theId;
+    }
+}

contracts/mocks/CrowdsaleMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.5.0;
+
+import "../crowdsale/Crowdsale.sol";
+
+contract CrowdsaleMock is Crowdsale {
+    constructor (uint256 rate, address payable wallet, IERC20 token) public Crowdsale(rate, wallet, token) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+}

contracts/mocks/DestructibleMock.sol

@@ -1,8 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../lifecycle/Destructible.sol";
-
-
-contract DestructibleMock is Destructible {
-  function() public payable {}
-}

contracts/mocks/DetailedERC20Mock.sol

@@ -1,16 +1,13 @@
-pragma solidity ^0.4.24;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/StandardToken.sol";
-import "../token/ERC20/DetailedERC20.sol";
+import "../token/ERC20/ERC20.sol";
+import "../token/ERC20/ERC20Detailed.sol";
 
-
-contract DetailedERC20Mock is StandardToken, DetailedERC20 {
-  constructor(
-    string _name,
-    string _symbol,
-    uint8 _decimals
-  )
-    DetailedERC20(_name, _symbol, _decimals)
-    public
-  {}
+contract ERC20DetailedMock is ERC20, ERC20Detailed {
+    constructor (string memory name, string memory symbol, uint8 decimals)
+        public
+        ERC20Detailed(name, symbol, decimals)
+    {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/mocks/ECDSAMock.sol

@@ -0,0 +1,15 @@
+pragma solidity ^0.5.0;
+
+import "../cryptography/ECDSA.sol";
+
+contract ECDSAMock {
+    using ECDSA for bytes32;
+
+    function recover(bytes32 hash, bytes memory signature) public pure returns (address) {
+        return hash.recover(signature);
+    }
+
+    function toEthSignedMessageHash(bytes32 hash) public pure returns (bytes32) {
+        return hash.toEthSignedMessageHash();
+    }
+}

contracts/mocks/ECRecoveryMock.sol

@@ -1,25 +0,0 @@
-pragma solidity ^0.4.24;
-
-
-import "../ECRecovery.sol";
-
-
-contract ECRecoveryMock {
-  using ECRecovery for bytes32;
-
-  function recover(bytes32 _hash, bytes _sig)
-    public
-    pure
-    returns (address)
-  {
-    return _hash.recover(_sig);
-  }
-
-  function toEthSignedMessageHash(bytes32 _hash)
-    public
-    pure
-    returns (bytes32)
-  {
-    return _hash.toEthSignedMessageHash();
-  }
-}

contracts/mocks/ERC165/ERC165InterfacesSupported.sol

@@ -0,0 +1,56 @@
+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.
+ * > 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)'))
+     */
+
+    /**
+     * @dev a mapping of interface id to whether or not it's supported
+     */
+    mapping(bytes4 => bool) private _supportedInterfaces;
+
+    /**
+     * @dev A contract implementing SupportsInterfaceWithLookup
+     * implement ERC165 itself
+     */
+    constructor () public {
+        _registerInterface(INTERFACE_ID_ERC165);
+    }
+
+    /**
+     * @dev implement supportsInterface(bytes4) using a lookup table
+     */
+    function supportsInterface(bytes4 interfaceId) external view 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[] memory interfaceIds) public {
+        for (uint256 i = 0; i < interfaceIds.length; i++) {
+            _registerInterface(interfaceIds[i]);
+        }
+    }
+}

contracts/mocks/ERC165/ERC165NotSupported.sol

@@ -0,0 +1,5 @@
+pragma solidity ^0.5.0;
+
+contract ERC165NotSupported {
+    // solhint-disable-previous-line no-empty-blocks
+}

contracts/mocks/ERC165CheckerMock.sol

@@ -0,0 +1,19 @@
+pragma solidity ^0.5.0;
+
+import "../introspection/ERC165Checker.sol";
+
+contract ERC165CheckerMock {
+    using ERC165Checker for address;
+
+    function supportsERC165(address account) public view returns (bool) {
+        return account._supportsERC165();
+    }
+
+    function supportsInterface(address account, bytes4 interfaceId) public view returns (bool) {
+        return account._supportsInterface(interfaceId);
+    }
+
+    function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) public view returns (bool) {
+        return account._supportsAllInterfaces(interfaceIds);
+    }
+}

contracts/mocks/ERC165Mock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.5.0;
+
+import "../introspection/ERC165.sol";
+
+contract ERC165Mock is ERC165 {
+    function registerInterface(bytes4 interfaceId) public {
+        _registerInterface(interfaceId);
+    }
+}

contracts/mocks/ERC20BurnableMock.sol

@@ -0,0 +1,9 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC20/ERC20Burnable.sol";
+
+contract ERC20BurnableMock is ERC20Burnable {
+    constructor (address initialAccount, uint256 initialBalance) public {
+        _mint(initialAccount, initialBalance);
+    }
+}

contracts/mocks/ERC20MintableMock.sol

@@ -0,0 +1,8 @@
+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

@@ -0,0 +1,22 @@
+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);
+    }
+
+    function mint(address account, uint256 amount) public {
+        _mint(account, amount);
+    }
+
+    function burn(address account, uint256 amount) public {
+        _burn(account, amount);
+    }
+
+    function burnFrom(address account, uint256 amount) public {
+        _burnFrom(account, amount);
+    }
+}

contracts/mocks/ERC20PausableMock.sol

@@ -0,0 +1,11 @@
+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 {
+        _mint(initialAccount, initialBalance);
+    }
+}

contracts/mocks/ERC20WithMetadataMock.sol

@@ -1,12 +1,10 @@
-pragma solidity ^0.4.21;
+pragma solidity ^0.5.0;
 
-import "../token/ERC20/StandardToken.sol";
-import "../proposals/ERC1046/TokenMetadata.sol";
+import "../token/ERC20/ERC20.sol";
+import "../drafts/ERC1046/TokenMetadata.sol";
 
-
-contract ERC20WithMetadataMock is StandardToken, ERC20WithMetadata {
-  constructor(string _tokenURI) public
-    ERC20WithMetadata(_tokenURI)
-  {
-  }
+contract ERC20WithMetadataMock is ERC20, ERC20WithMetadata {
+    constructor (string memory tokenURI) public ERC20WithMetadata(tokenURI) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
 }

contracts/mocks/ERC223TokenMock.sol

@@ -1,34 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../token/ERC20/BasicToken.sol";
-
-
-contract ERC223ContractInterface {
-  function tokenFallback(address _from, uint256 _value, bytes _data) external;
-}
-
-
-contract ERC223TokenMock is BasicToken {
-
-  constructor(address _initialAccount, uint256 _initialBalance) public {
-    balances[_initialAccount] = _initialBalance;
-    totalSupply_ = _initialBalance;
-  }
-
-  // ERC223 compatible transfer function (except the name)
-  function transferERC223(address _to, uint256 _value, bytes _data) public
-    returns (bool success)
-  {
-    transfer(_to, _value);
-    bool isContract = false;
-    // solium-disable-next-line security/no-inline-assembly
-    assembly {
-      isContract := not(iszero(extcodesize(_to)))
-    }
-    if (isContract) {
-      ERC223ContractInterface receiver = ERC223ContractInterface(_to);
-      receiver.tokenFallback(msg.sender, _value, _data);
-    }
-    return true;
-  }
-}

contracts/mocks/ERC721BasicTokenMock.sol

@@ -1,18 +0,0 @@
-pragma solidity ^0.4.24;
-
-import "../token/ERC721/ERC721BasicToken.sol";
-
-
-/**
- * @title ERC721BasicTokenMock
- * This mock just provides a public mint and burn functions for testing purposes
- */
-contract ERC721BasicTokenMock is ERC721BasicToken {
-  function mint(address _to, uint256 _tokenId) public {
-    super._mint(_to, _tokenId);
-  }
-
-  function burn(uint256 _tokenId) public {
-    super._burn(ownerOf(_tokenId), _tokenId);
-  }
-}

contracts/mocks/ERC721FullMock.sol

@@ -0,0 +1,29 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC721/ERC721Full.sol";
+import "../token/ERC721/ERC721Mintable.sol";
+import "../token/ERC721/ERC721MetadataMintable.sol";
+import "../token/ERC721/ERC721Burnable.sol";
+
+/**
+ * @title ERC721FullMock
+ * This mock just provides public functions for setting metadata URI, getting all tokens of an owner,
+ * checking token existence, removal of a token from an address
+ */
+contract ERC721FullMock is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
+    constructor (string memory name, string memory symbol) public ERC721Mintable() ERC721Full(name, symbol) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+
+    function exists(uint256 tokenId) public view returns (bool) {
+        return _exists(tokenId);
+    }
+
+    function tokensOfOwner(address owner) public view returns (uint256[] memory) {
+        return _tokensOfOwner(owner);
+    }
+
+    function setTokenURI(uint256 tokenId, string memory uri) public {
+        _setTokenURI(tokenId, uri);
+    }
+}

contracts/mocks/ERC721MintableBurnableImpl.sol

@@ -0,0 +1,15 @@
+pragma solidity ^0.5.0;
+
+import "../token/ERC721/ERC721Full.sol";
+import "../token/ERC721/ERC721Mintable.sol";
+import "../token/ERC721/ERC721MetadataMintable.sol";
+import "../token/ERC721/ERC721Burnable.sol";
+
+/**
+ * @title ERC721MintableBurnableImpl
+ */
+contract ERC721MintableBurnableImpl is ERC721Full, ERC721Mintable, ERC721MetadataMintable, ERC721Burnable {
+    constructor () public ERC721Mintable() ERC721Full("Test", "TEST") {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+}