Add tests for dev-utils package

packages/dev-utils/test/rpc_test.ts

@@ -0,0 +1,42 @@
+import { BlockParamLiteral } from '@0xproject/types';
+import { Web3Wrapper } from '@0xproject/web3-wrapper';
+import * as chai from 'chai';
+import 'mocha';
+
+import { RPC, web3Factory } from '../src';
+
+const expect = chai.expect;
+
+describe('RPC tests', () => {
+    const web3 = web3Factory.create();
+    const web3Wrapper = new Web3Wrapper(web3.currentProvider);
+    const rpc = new RPC();
+    describe('#mineBlockAsync', () => {
+        it('increases block number when called', async () => {
+            const blockNumberBefore = await web3Wrapper.getBlockNumberAsync();
+            await rpc.mineBlockAsync();
+            const blockNumberAfter = await web3Wrapper.getBlockNumberAsync();
+            expect(blockNumberAfter).to.be.equal(blockNumberBefore + 1);
+        });
+    });
+    describe('#increaseTimeAsync', () => {
+        it('increases time when called', async () => {
+            const TIME_DELTA = 1000;
+            const blockTimestamtBefore = await web3Wrapper.getBlockTimestampAsync(BlockParamLiteral.Latest);
+            await rpc.increaseTimeAsync(TIME_DELTA);
+            await rpc.mineBlockAsync();
+            const blockTimestamtAfter = await web3Wrapper.getBlockTimestampAsync(BlockParamLiteral.Latest);
+            expect(blockTimestamtAfter).to.be.at.least(blockTimestamtBefore + TIME_DELTA);
+        });
+    });
+    describe('#takeSnapshotAsync/revertSnapshotAsync', () => {
+        it('reverts changes in between', async () => {
+            const blockNumberBefore = await web3Wrapper.getBlockNumberAsync();
+            const snapshotId = await rpc.takeSnapshotAsync();
+            await rpc.mineBlockAsync();
+            await rpc.revertSnapshotAsync(snapshotId);
+            const blockNumberAfter = await web3Wrapper.getBlockNumberAsync();
+            expect(blockNumberAfter).to.be.equal(blockNumberBefore);
+        });
+    });
+});