Fix inconsistencies in contract/test hierachy (#2814)

* Fix inconsistencies in contract/test hierachy

* changelog entry

test/proxy/utils/Initializable.test.js

@@ -0,0 +1,79 @@
+const { expectRevert } = require('@openzeppelin/test-helpers');
+
+const { assert } = require('chai');
+
+const InitializableMock = artifacts.require('InitializableMock');
+const SampleChild = artifacts.require('SampleChild');
+
+contract('Initializable', function (accounts) {
+  describe('basic testing without inheritance', function () {
+    beforeEach('deploying', async function () {
+      this.contract = await InitializableMock.new();
+    });
+
+    context('before initialize', function () {
+      it('initializer has not run', async function () {
+        assert.isFalse(await this.contract.initializerRan());
+      });
+    });
+
+    context('after initialize', function () {
+      beforeEach('initializing', async function () {
+        await this.contract.initialize();
+      });
+
+      it('initializer has run', async function () {
+        assert.isTrue(await this.contract.initializerRan());
+      });
+
+      it('initializer does not run again', async function () {
+        await expectRevert(this.contract.initialize(), 'Initializable: contract is already initialized');
+      });
+    });
+
+    context('after nested initialize', function () {
+      beforeEach('initializing', async function () {
+        await this.contract.initializeNested();
+      });
+
+      it('initializer has run', async function () {
+        assert.isTrue(await this.contract.initializerRan());
+      });
+    });
+  });
+
+  describe('complex testing with inheritance', function () {
+    const mother = 12;
+    const gramps = '56';
+    const father = 34;
+    const child = 78;
+
+    beforeEach('deploying', async function () {
+      this.contract = await SampleChild.new();
+    });
+
+    beforeEach('initializing', async function () {
+      await this.contract.initialize(mother, gramps, father, child);
+    });
+
+    it('initializes human', async function () {
+      assert.equal(await this.contract.isHuman(), true);
+    });
+
+    it('initializes mother', async function () {
+      assert.equal(await this.contract.mother(), mother);
+    });
+
+    it('initializes gramps', async function () {
+      assert.equal(await this.contract.gramps(), gramps);
+    });
+
+    it('initializes father', async function () {
+      assert.equal(await this.contract.father(), father);
+    });
+
+    it('initializes child', async function () {
+      assert.equal(await this.contract.child(), child);
+    });
+  });
+});

test/proxy/utils/UUPSUpgradeable.test.js

@@ -0,0 +1,72 @@
+const { expectEvent, expectRevert } = require('@openzeppelin/test-helpers');
+
+const ERC1967Proxy = artifacts.require('ERC1967Proxy');
+const UUPSUpgradeableMock = artifacts.require('UUPSUpgradeableMock');
+const UUPSUpgradeableUnsafeMock = artifacts.require('UUPSUpgradeableUnsafeMock');
+const UUPSUpgradeableBrokenMock = artifacts.require('UUPSUpgradeableBrokenMock');
+const CountersImpl = artifacts.require('CountersImpl');
+
+contract('UUPSUpgradeable', function (accounts) {
+  before(async function () {
+    this.implInitial = await UUPSUpgradeableMock.new();
+    this.implUpgradeOk = await UUPSUpgradeableMock.new();
+    this.implUpgradeUnsafe = await UUPSUpgradeableUnsafeMock.new();
+    this.implUpgradeBroken = await UUPSUpgradeableBrokenMock.new();
+    this.implUpgradeNonUUPS = await CountersImpl.new();
+  });
+
+  beforeEach(async function () {
+    const { address } = await ERC1967Proxy.new(this.implInitial.address, '0x');
+    this.instance = await UUPSUpgradeableMock.at(address);
+  });
+
+  it('upgrade to upgradeable implementation', async function () {
+    const { receipt } = await this.instance.upgradeTo(this.implUpgradeOk.address);
+    expect(receipt.logs.filter(({ event }) => event === 'Upgraded').length).to.be.equal(1);
+    expectEvent(receipt, 'Upgraded', { implementation: this.implUpgradeOk.address });
+  });
+
+  it('upgrade to upgradeable implementation with call', async function () {
+    expect(await this.instance.current()).to.be.bignumber.equal('0');
+
+    const { receipt } = await this.instance.upgradeToAndCall(
+      this.implUpgradeOk.address,
+      this.implUpgradeOk.contract.methods.increment().encodeABI(),
+    );
+    expect(receipt.logs.filter(({ event }) => event === 'Upgraded').length).to.be.equal(1);
+    expectEvent(receipt, 'Upgraded', { implementation: this.implUpgradeOk.address });
+
+    expect(await this.instance.current()).to.be.bignumber.equal('1');
+  });
+
+  it('upgrade to and unsafe upgradeable implementation', async function () {
+    const { receipt } = await this.instance.upgradeTo(this.implUpgradeUnsafe.address);
+    expectEvent(receipt, 'Upgraded', { implementation: this.implUpgradeUnsafe.address });
+  });
+
+  it('reject upgrade to broken upgradeable implementation', async function () {
+    await expectRevert(
+      this.instance.upgradeTo(this.implUpgradeBroken.address),
+      'ERC1967Upgrade: upgrade breaks further upgrades',
+    );
+  });
+
+  // delegate to a non existing upgradeTo function causes a low level revert
+  it('reject upgrade to non uups implementation', async function () {
+    await expectRevert(
+      this.instance.upgradeTo(this.implUpgradeNonUUPS.address),
+      'Address: low-level delegate call failed',
+    );
+  });
+
+  it('reject proxy address as implementation', async function () {
+    const { address } = await ERC1967Proxy.new(this.implInitial.address, '0x');
+    const otherInstance = await UUPSUpgradeableMock.at(address);
+
+    // infinite loop reverts when a nested call is out-of-gas
+    await expectRevert(
+      this.instance.upgradeTo(otherInstance.address),
+      'Address: low-level delegate call failed',
+    );
+  });
+});