build: replace prepare-e2e script by inline yarn install in test (#940

)

e2e/__tests__/custom-typings.test.ts

@@ -1,5 +1,13 @@
+import path from 'path';
+
 import runJest from '../run-jest';
-import { onNodeVersions } from '../utils';
+import { onNodeVersions, runYarnInstall } from '../utils';
+
+const dir = path.resolve(__dirname, '../custom-typings');
+
+beforeEach(() => {
+  runYarnInstall(dir);
+});
 
 test('support custom typings', () => {
   const result = runJest('custom-typings');

e2e/__tests__/with-babel.test.ts

@@ -1,15 +1,25 @@
+import path from 'path';
+
 import runJest from '../run-jest';
-import { onNodeVersions } from '../utils';
+import { onNodeVersions, runYarnInstall } from '../utils';
+
+const dir = path.resolve(__dirname, '../with-babel');
+
+beforeEach(() => {
+  runYarnInstall(dir);
+});
 
 test('support using with Babel', () => {
-  const result = runJest('with-babel');
+  // --no-cache because babel can cache stuff and result in false green
+  const result = runJest('with-babel', ['--no-cache']);
 
   expect(result.exitCode).toBe(0);
 });
 
 onNodeVersions('^12.17.0 || >=13.2.0', () => {
   test('support using with Babel in ESM mode', () => {
-    const result = runJest('with-babel', ['-c=jest-esm.config.js'], {
+    // --no-cache because babel can cache stuff and result in false green
+    const result = runJest('with-babel', ['-c=jest-esm.config.js', '--no-cache'], {
       nodeOptions: '--experimental-vm-modules',
     });
 

e2e/utils.ts

@@ -1,5 +1,15 @@
+import fs from 'fs';
+import path from 'path';
+
+import type { Config } from '@jest/types';
+import { ExecaReturnValue, sync as spawnSync } from 'execa';
 import semver from 'semver';
 
+interface RunResult extends ExecaReturnValue {
+  status: number;
+  error: Error;
+}
+
 export const normalizeIcons = (str: string): string => {
   if (!str) {
     return str;
@@ -9,7 +19,42 @@ export const normalizeIcons = (str: string): string => {
   return str.replace(new RegExp('\u00D7', 'g'), '\u2715').replace(new RegExp('\u221A', 'g'), '\u2713');
 };
 
-export function onNodeVersions(versionRange: string, testBody: () => void): void {
+const run = (cmd: string, cwd?: Config.Path, env?: Record<string, string>): RunResult => {
+  const args = cmd.split(/\s/).slice(1);
+  const spawnOptions = { cwd, env, preferLocal: false, reject: false };
+  const result = spawnSync(cmd.split(/\s/)[0], args, spawnOptions) as RunResult;
+
+  // For compat with cross-spawn
+  result.status = result.exitCode;
+
+  if (result.status !== 0) {
+    const message = `
+      ORIGINAL CMD: ${cmd}
+      STDOUT: ${result.stdout}
+      STDERR: ${result.stderr}
+      STATUS: ${result.status}
+      ERROR: ${result.error}
+    `;
+    throw new Error(message);
+  }
+
+  return result;
+};
+
+export const runYarnInstall = (cwd: Config.Path, env?: Record<string, string>): RunResult => {
+  const lockfilePath = path.resolve(cwd, 'yarn.lock');
+  let exists = true;
+
+  // If the lockfile doesn't exist, yarn's project detection is confused. Just creating an empty file works
+  if (!fs.existsSync(lockfilePath)) {
+    exists = false;
+    fs.writeFileSync(lockfilePath, '');
+  }
+
+  return run(exists ? 'yarn install --immutable' : 'yarn install', cwd, env);
+};
+
+export const onNodeVersions = (versionRange: string, testBody: () => void): void => {
   const description = `on node ${versionRange}`;
   if (semver.satisfies(process.versions.node, versionRange)) {
     // eslint-disable-next-line jest/valid-title
@@ -22,4 +67,4 @@ export function onNodeVersions(versionRange: string, testBody: () => void): void
       testBody();
     });
   }
-}
+};

package.json

@@ -40,7 +40,7 @@
     "lint:fix": "eslint --fix --ext .js,.ts .",
     "lint:prettier": "prettier '**/*.{yml,yaml}' 'website/**/*.{css,js,md}' 'README.md' --write --ignore-path .gitignore",
     "lint:prettier-ci": "prettier '**/*.{yml,yaml}' 'website/**/*.{css,js,md}' 'README.md' --check --ignore-path .gitignore",
-    "test": "node scripts/prepare-e2e.js && jest",
+    "test": "jest",
     "test:examples": "node scripts/test-examples.js",
     "doc": "cd website && yarn start",
     "doc:build": "cd website && yarn build",