Add unit test specific to Address utils (#1251) (#1316)

test/Address.test.js

@@ -0,0 +1,20 @@
+const AddressImpl = artifacts.require('AddressImpl');
+const SimpleToken = artifacts.require('SimpleToken');
+
+require('chai')
+  .should();
+
+contract('Address', function ([_, anyone]) {
+  beforeEach(async function () {
+    this.mock = await AddressImpl.new();
+  });
+
+  it('should return false for account address', async function () {
+    (await this.mock.isContract(anyone)).should.equal(false);
+  });
+
+  it('should return true for contract address', async function () {
+    const contract = await SimpleToken.new();
+    (await this.mock.isContract(contract.address)).should.equal(true);
+  });
+});