Transfer replacement (#1962)

* Add Address.sendEther

* Add documentation to sendEther

* Add changelog entry

* Rename sendEther to sendValue

test/utils/Address.test.js

@@ -1,10 +1,11 @@
-const { constants } = require('@openzeppelin/test-helpers');
+const { balance, constants, ether, expectRevert, send } = require('@openzeppelin/test-helpers');
 const { expect } = require('chai');
 
 const AddressImpl = artifacts.require('AddressImpl');
 const SimpleToken = artifacts.require('SimpleToken');
+const EtherReceiver = artifacts.require('EtherReceiverMock');
 
-contract('Address', function ([_, other]) {
+contract('Address', function ([_, recipient, other]) {
   const ALL_ONES_ADDRESS = '0xFFfFfFffFFfffFFfFFfFFFFFffFFFffffFfFFFfF';
 
   beforeEach(async function () {
@@ -35,4 +36,71 @@ contract('Address', function ([_, other]) {
       expect(await this.mock.toPayable(ALL_ONES_ADDRESS)).to.equal(ALL_ONES_ADDRESS);
     });
   });
+
+  describe('sendValue', function () {
+    beforeEach(async function () {
+      this.recipientTracker = await balance.tracker(recipient);
+    });
+
+    context('when sender contract has no funds', function () {
+      it('sends 0 wei', async function () {
+        await this.mock.sendValue(other, 0);
+
+        expect(await this.recipientTracker.delta()).to.be.bignumber.equal('0');
+      });
+
+      it('reverts when sending non-zero amounts', async function () {
+        await expectRevert(this.mock.sendValue(other, 1), 'Address: insufficient balance');
+      });
+    });
+
+    context('when sender contract has funds', function () {
+      const funds = ether('1');
+      beforeEach(async function () {
+        await send.ether(other, this.mock.address, funds);
+      });
+
+      it('sends 0 wei', async function () {
+        await this.mock.sendValue(recipient, 0);
+        expect(await this.recipientTracker.delta()).to.be.bignumber.equal('0');
+      });
+
+      it('sends non-zero amounts', async function () {
+        await this.mock.sendValue(recipient, funds.subn(1));
+        expect(await this.recipientTracker.delta()).to.be.bignumber.equal(funds.subn(1));
+      });
+
+      it('sends the whole balance', async function () {
+        await this.mock.sendValue(recipient, funds);
+        expect(await this.recipientTracker.delta()).to.be.bignumber.equal(funds);
+        expect(await balance.current(this.mock.address)).to.be.bignumber.equal('0');
+      });
+
+      it('reverts when sending more than the balance', async function () {
+        await expectRevert(this.mock.sendValue(recipient, funds.addn(1)), 'Address: insufficient balance');
+      });
+
+      context('with contract recipient', function () {
+        beforeEach(async function () {
+          this.contractRecipient = await EtherReceiver.new();
+        });
+
+        it('sends funds', async function () {
+          const tracker = await balance.tracker(this.contractRecipient.address);
+
+          await this.contractRecipient.setAcceptEther(true);
+          await this.mock.sendValue(this.contractRecipient.address, funds);
+          expect(await tracker.delta()).to.be.bignumber.equal(funds);
+        });
+
+        it('reverts on recipient revert', async function () {
+          await this.contractRecipient.setAcceptEther(false);
+          await expectRevert(
+            this.mock.sendValue(this.contractRecipient.address, funds),
+            'Address: unable to send value, recipient may have reverted'
+          );
+        });
+      });
+    });
+  });
 });