Add bytes32 to bytes32 enumerable map (#3192)

* feat(enumerablemap): add bytes32 to bytes32 map

* chore(changelog): edit CHANGELOG

* feat(enumerable map): edit struct visibility

test/utils/structs/EnumerableMap.behavior.js

@@ -0,0 +1,181 @@
+const { expectEvent, expectRevert } = require('@openzeppelin/test-helpers');
+const { expect } = require('chai');
+
+const zip = require('lodash.zip');
+
+function shouldBehaveLikeMap (keys, values, zeroValue) {
+  const [keyA, keyB, keyC] = keys;
+  const [valueA, valueB, valueC] = values;
+
+  async function expectMembersMatch (map, keys, values) {
+    expect(keys.length).to.equal(values.length);
+
+    await Promise.all(keys.map(async key =>
+      expect(await map.contains(key)).to.equal(true),
+    ));
+
+    expect(await map.length()).to.bignumber.equal(keys.length.toString());
+
+    expect(
+      (await Promise.all(keys.map(key => map.get(key)))).map(k => k.toString()),
+    ).to.have.same.members(
+      values.map(value => value.toString()),
+    );
+
+    // To compare key-value pairs, we zip keys and values, and convert BNs to
+    // strings to workaround Chai limitations when dealing with nested arrays
+    expect(await Promise.all([...Array(keys.length).keys()].map(async (index) => {
+      const entry = await map.at(index);
+      return [entry.key.toString(), entry.value.toString()];
+    }))).to.have.same.deep.members(
+      zip(keys.map(k => k.toString()), values.map(v => v.toString())),
+    );
+  }
+
+  it('starts empty', async function () {
+    expect(await this.map.contains(keyA)).to.equal(false);
+
+    await expectMembersMatch(this.map, [], []);
+  });
+
+  describe('set', function () {
+    it('adds a key', async function () {
+      const receipt = await this.map.set(keyA, valueA);
+      expectEvent(receipt, 'OperationResult', { result: true });
+
+      await expectMembersMatch(this.map, [keyA], [valueA]);
+    });
+
+    it('adds several keys', async function () {
+      await this.map.set(keyA, valueA);
+      await this.map.set(keyB, valueB);
+
+      await expectMembersMatch(this.map, [keyA, keyB], [valueA, valueB]);
+      expect(await this.map.contains(keyC)).to.equal(false);
+    });
+
+    it('returns false when adding keys already in the set', async function () {
+      await this.map.set(keyA, valueA);
+
+      const receipt = (await this.map.set(keyA, valueA));
+      expectEvent(receipt, 'OperationResult', { result: false });
+
+      await expectMembersMatch(this.map, [keyA], [valueA]);
+    });
+
+    it('updates values for keys already in the set', async function () {
+      await this.map.set(keyA, valueA);
+
+      await this.map.set(keyA, valueB);
+
+      await expectMembersMatch(this.map, [keyA], [valueB]);
+    });
+  });
+
+  describe('remove', function () {
+    it('removes added keys', async function () {
+      await this.map.set(keyA, valueA);
+
+      const receipt = await this.map.remove(keyA);
+      expectEvent(receipt, 'OperationResult', { result: true });
+
+      expect(await this.map.contains(keyA)).to.equal(false);
+      await expectMembersMatch(this.map, [], []);
+    });
+
+    it('returns false when removing keys not in the set', async function () {
+      const receipt = await this.map.remove(keyA);
+      expectEvent(receipt, 'OperationResult', { result: false });
+
+      expect(await this.map.contains(keyA)).to.equal(false);
+    });
+
+    it('adds and removes multiple keys', async function () {
+      // []
+
+      await this.map.set(keyA, valueA);
+      await this.map.set(keyC, valueC);
+
+      // [A, C]
+
+      await this.map.remove(keyA);
+      await this.map.remove(keyB);
+
+      // [C]
+
+      await this.map.set(keyB, valueB);
+
+      // [C, B]
+
+      await this.map.set(keyA, valueA);
+      await this.map.remove(keyC);
+
+      // [A, B]
+
+      await this.map.set(keyA, valueA);
+      await this.map.set(keyB, valueB);
+
+      // [A, B]
+
+      await this.map.set(keyC, valueC);
+      await this.map.remove(keyA);
+
+      // [B, C]
+
+      await this.map.set(keyA, valueA);
+      await this.map.remove(keyB);
+
+      // [A, C]
+
+      await expectMembersMatch(this.map, [keyA, keyC], [valueA, valueC]);
+
+      expect(await this.map.contains(keyB)).to.equal(false);
+    });
+  });
+
+  describe('read', function () {
+    beforeEach(async function () {
+      await this.map.set(keyA, valueA);
+    });
+
+    describe('get', function () {
+      it('existing value', async function () {
+        expect(
+          (await this.map.get(keyA)).toString(),
+        ).to.be.equal(valueA.toString());
+      });
+      it('missing value', async function () {
+        await expectRevert(this.map.get(keyB), 'EnumerableMap: nonexistent key');
+      });
+    });
+
+    describe('get with message', function () {
+      it('existing value', async function () {
+        expect(
+          (await this.map.getWithMessage(keyA, 'custom error string'))
+            .toString(),
+        ).to.be.equal(valueA.toString());
+      });
+      it('missing value', async function () {
+        await expectRevert(this.map.getWithMessage(keyB, 'custom error string'), 'custom error string');
+      });
+    });
+
+    describe('tryGet', function () {
+      it('existing value', async function () {
+        const result = await this.map.tryGet(keyA);
+        expect(result['0']).to.be.equal(true);
+        expect(result['1'].toString()).to.be.equal(valueA.toString());
+      });
+      it('missing value', async function () {
+        const result = await this.map.tryGet(keyB);
+        expect(result['0']).to.be.equal(false);
+        expect(result['1'].toString()).to.be.equal(zeroValue.toString());
+      });
+    });
+  });
+}
+
+module.exports = {
+  shouldBehaveLikeMap,
+};