EVM Package examples (#32)

* Added StandardToken (on-chain lib)

* Added OnChainERC20 example.

* Added OnChainERC721

* Update OnChainERC721.test.js

* Renamed the contracts to Standalone*.

* Fix path to Initializable in StandardToken example

test/examples/StandardToken.test.js

@@ -0,0 +1,96 @@
+const encodeCall = require('zos-lib/lib/helpers/encodeCall').default;
+const { shouldBehaveLikeERC20Mintable } = require('../token/ERC20/behaviors/ERC20Mintable.behavior');
+const { shouldBehaveLikePublicRole } = require('../access/roles/PublicRole.behavior');
+
+const BigNumber = web3.BigNumber;
+
+const should = require('chai')
+  .use(require('chai-bignumber')(BigNumber))
+  .should();
+
+const StandardToken = artifacts.require('StandardToken');
+
+contract('StandardToken', function ([_, deployer, initialHolder, minterA, minterB, pauserA, pauserB, anyone, ...otherAccounts]) {
+  const name = "StdToken";
+  const symbol = "STDT";
+  const decimals = 18;
+
+  const initialSupply = 300;
+
+  const minters = [minterA, minterB];
+  const pausers = [pauserA, pauserB];
+
+  const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
+
+  beforeEach(async function () {
+    this.token = await StandardToken.new({ from: deployer });
+  });
+
+  async function initialize(token, name, symbol, decimals, initialSupply, initialHolder, minters, pausers, from) {
+    const callData = encodeCall('initialize', ['string', 'string', 'uint8', 'uint256', 'address', 'address[]', 'address[]'], [name, symbol, decimals, initialSupply, initialHolder, minters, pausers]);
+    await token.sendTransaction({ data: callData, from });
+  }
+
+  context('with all arguments', function () {
+    beforeEach(async function () {
+      await initialize(this.token, name, symbol, decimals, initialSupply, initialHolder, minters, pausers, deployer);
+    });
+
+    it('initializes metadata', async function () {
+      (await this.token.name()).should.equal(name);
+      (await this.token.symbol()).should.equal(symbol);
+      (await this.token.decimals()).should.be.bignumber.equal(decimals);
+    });
+
+    it('assigns the initial supply to the initial holder', async function () {
+      (await this.token.balanceOf(initialHolder)).should.be.bignumber.equal(initialSupply);
+    });
+
+    describe('mintability', function () {
+      beforeEach(function () {
+        this.contract = this.token;
+      });
+
+      it('all minters have the minter role', async function () {
+        for (const minter of minters) {
+          (await this.token.isMinter(minter)).should.equal(true);
+        }
+      });
+
+      shouldBehaveLikeERC20Mintable(minterA, otherAccounts);
+    });
+
+    describe('pausability', function () {
+      beforeEach(function () {
+        this.contract = this.token;
+      });
+
+      it('all pausers have the minter role', async function () {
+        for (const pauser of pausers) {
+          (await this.token.isPauser(pauser)).should.equal(true);
+        }
+      });
+    });
+  });
+
+  it('can be created with zero initial balance', async function () {
+    await initialize(this.token, name, symbol, decimals, 0, ZERO_ADDRESS, minters, pausers, deployer);
+    (await this.token.balanceOf(initialHolder)).should.be.bignumber.equal(0);
+  });
+
+  it('can be created with no minters', async function () {
+    await initialize(this.token, name, symbol, decimals, initialSupply, initialHolder, [], pausers, deployer);
+
+    for (const minter of minters) {
+      (await this.token.isMinter(minter)).should.equal(false);
+    }
+  });
+
+  it('can be created with no pausers', async function () {
+    await initialize(this.token, name, symbol, decimals, initialSupply, initialHolder, minters, [], deployer);
+
+    for (const pauser of pausers) {
+      (await this.token.isPauser(pauser)).should.equal(false);
+    }
+  });
+});