Add release script snapshot test

Author: Brian Vaughn

scripts/release/prepare-stable-commands/check-out-packages.js

@@ -3,11 +3,21 @@
 'use strict';
 
 const {exec} = require('child-process-promise');
+const {existsSync} = require('fs');
 const {join} = require('path');
 const {logPromise} = require('../utils');
 const theme = require('../theme');
 
-const run = async ({cwd, packages, version}) => {
+const run = async ({cwd, local, packages, version}) => {
+  if (local) {
+    // Sanity test
+    if (!existsSync(join(cwd, 'build', 'node_modules', 'react'))) {
+      console.error(theme.error`No local build exists.`);
+      process.exit(1);
+    }
+    return;
+  }
+
   // Cleanup from previous builds
   await exec(`rm -rf ./build/node_modules*`, {cwd});
   await exec(`mkdir ./build/node_modules`, {cwd});

scripts/release/prepare-stable-commands/parse-params.js

@@ -6,6 +6,13 @@ const commandLineArgs = require('command-line-args');
 const commandLineUsage = require('command-line-usage');
 
 const paramDefinitions = [
+  {
+    name: 'local',
+    type: Boolean,
+    description:
+      'Skip NPM and use the build already present in "build/node_modules".',
+    defaultValue: false,
+  },
   {
     name: 'version',
     type: String,

scripts/release/test.js

@@ -0,0 +1,77 @@
+#!/usr/bin/env node
+
+'use strict';
+
+const {exec, spawn} = require('child-process-promise');
+const clear = require('clear');
+const {join} = require('path');
+const {readFileSync} = require('fs');
+const theme = require('./theme');
+const {printDiff} = require('./utils');
+
+const cwd = join(__dirname, '..', '..');
+
+const run = async () => {
+  const defaultOptions = {
+    cwd,
+    stdio: [process.stdin, process.stdout, process.stderr],
+    env: process.env,
+  };
+
+  try {
+    // Start with a known build/revision:
+    // https://circleci.com/gh/facebook/react/12707
+    await spawn(
+      'node',
+      ['./scripts/release/prepare-canary.js', '--build=12707'],
+      defaultOptions
+    );
+    await spawn(
+      'node',
+      [
+        './scripts/release/prepare-stable.js',
+        '--version=0.0.0-b3d1a81a9',
+        '--local',
+      ],
+      defaultOptions
+    );
+
+    const beforeContents = readFileSync(
+      'scripts/release/test.snapshot',
+      'utf-8',
+      {cwd}
+    );
+    await exec('cp build/temp.diff scripts/release/test.snapshot');
+    const afterContents = readFileSync(
+      'scripts/release/test.snapshot',
+      'utf-8',
+      {cwd}
+    );
+
+    clear();
+
+    if (beforeContents === afterContents) {
+      console.log(theme.header`Snapshot test passed.`);
+    } else {
+      printDiff('scripts/release/test.snapshot', beforeContents, afterContents);
+      console.log();
+      console.error(theme.error('Snapshot test failed!'));
+      console.log();
+      console.log(
+        'If this failure was expected, please update the contents of the snapshot file:'
+      );
+      console.log(
+        theme`  {command git add} {path scripts/release/test.snapshot}`
+      );
+      console.log(
+        theme`  {command git commit -m "Updating release script snapshot file."}`
+      );
+      process.exit(1);
+    }
+  } catch (error) {
+    console.error(theme.error(error));
+    process.exit(1);
+  }
+};
+
+run();