feat: check for common errors when using the wrong test environment (#…

…8245)

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Features
 
+- `[jest-message-util]` Check for common errors when using the wrong test environment ([#8245](https://github.com/facebook/jest/pull/8245))
+
 ### Fixes
 
 - `[jest-circus]` Fix type ellision of jest-runtime imports ([#9717](https://github.com/facebook/jest/pull/9717))

e2e/__tests__/__snapshots__/wrongEnv.test.ts.snap

@@ -0,0 +1,115 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Wrong globals for environment print useful error for document 1`] = `
+FAIL __tests__/node.js
+  ✕ use document
+  ○ skipped use window
+  ○ skipped use navigator
+
+  ● use document
+
+    The error below may be caused by using the wrong test environment, see https://jestjs.io/docs/en/configuration#testenvironment-string.
+    Consider using the "jsdom" test environment.
+
+    ReferenceError: document is not defined
+
+      14 | 
+      15 | test('use document', () => {
+    > 16 |   const div = document.createElement('div');
+         |               ^
+      17 | 
+      18 |   console.log(div);
+      19 | 
+
+      at Object.document (__tests__/node.js:16:15)
+`;
+
+exports[`Wrong globals for environment print useful error for navigator 1`] = `
+FAIL __tests__/node.js
+  ✕ use navigator
+  ○ skipped use document
+  ○ skipped use window
+
+  ● use navigator
+
+    The error below may be caused by using the wrong test environment, see https://jestjs.io/docs/en/configuration#testenvironment-string.
+    Consider using the "jsdom" test environment.
+
+    ReferenceError: navigator is not defined
+
+      30 | 
+      31 | test('use navigator', () => {
+    > 32 |   const userAgent = navigator.userAgent;
+         |                     ^
+      33 | 
+      34 |   console.log(userAgent);
+      35 | 
+
+      at Object.navigator (__tests__/node.js:32:21)
+`;
+
+exports[`Wrong globals for environment print useful error for unref 1`] = `
+FAIL __tests__/jsdom.js
+  ✕ use unref
+
+  ● use unref
+
+    The error below may be caused by using the wrong test environment, see https://jestjs.io/docs/en/configuration#testenvironment-string.
+    Consider using the "node" test environment.
+
+    TypeError: setTimeout(...).unref is not a function
+
+      11 | 
+      12 | test('use unref', () => {
+    > 13 |   setTimeout(() => {}, 0).unref();
+         |                           ^
+      14 | 
+      15 |   expect(1).toBe(1);
+      16 | });
+
+      at Object.unref (__tests__/jsdom.js:13:27)
+`;
+
+exports[`Wrong globals for environment print useful error for window 1`] = `
+FAIL __tests__/node.js
+  ✕ use window
+  ○ skipped use document
+  ○ skipped use navigator
+
+  ● use window
+
+    The error below may be caused by using the wrong test environment, see https://jestjs.io/docs/en/configuration#testenvironment-string.
+    Consider using the "jsdom" test environment.
+
+    ReferenceError: window is not defined
+
+      22 | 
+      23 | test('use window', () => {
+    > 24 |   const location = window.location;
+         |                    ^
+      25 | 
+      26 |   console.log(location);
+      27 | 
+
+      at Object.window (__tests__/node.js:24:20)
+`;
+
+exports[`Wrong globals for environment print useful error when it explodes during evaluation 1`] = `
+FAIL __tests__/beforeTest.js
+  ● Test suite failed to run
+
+    The error below may be caused by using the wrong test environment, see https://jestjs.io/docs/en/configuration#testenvironment-string.
+    Consider using the "jsdom" test environment.
+
+    ReferenceError: document is not defined
+
+      11 | /* eslint-env browser */
+      12 | 
+    > 13 | const div = document.createElement('div');
+         |             ^
+      14 | 
+      15 | console.log(div);
+      16 | 
+
+      at Object.document (__tests__/beforeTest.js:13:13)
+`;

e2e/__tests__/wrongEnv.test.ts

@@ -0,0 +1,38 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import wrap from 'jest-snapshot-serializer-raw';
+import runJest from '../runJest';
+import {extractSummary} from '../Utils';
+
+function assertFailuresAndSnapshot(args: Array<string>) {
+  const result = runJest('wrong-env', args);
+  expect(result.exitCode).toBe(1);
+  expect(wrap(extractSummary(result.stderr).rest)).toMatchSnapshot();
+}
+
+describe('Wrong globals for environment', () => {
+  it('print useful error for window', () => {
+    assertFailuresAndSnapshot(['node', '-t=window']);
+  });
+
+  it('print useful error for document', () => {
+    assertFailuresAndSnapshot(['node', '-t=document']);
+  });
+
+  it('print useful error for navigator', () => {
+    assertFailuresAndSnapshot(['node', '-t=navigator']);
+  });
+
+  it('print useful error for unref', () => {
+    assertFailuresAndSnapshot(['jsdom', '-t=unref']);
+  });
+
+  it('print useful error when it explodes during evaluation', () => {
+    assertFailuresAndSnapshot(['beforeTest']);
+  });
+});

e2e/wrong-env/__tests__/beforeTest.js

@@ -0,0 +1,17 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @jest-environment node
+ *
+ */
+
+/* eslint-env browser */
+
+const div = document.createElement('div');
+
+console.log(div);
+
+test('stub', () => expect(1).toBe(1));

e2e/wrong-env/__tests__/jsdom.js

@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @jest-environment jsdom
+ */
+
+'use strict';
+
+test('use unref', () => {
+  setTimeout(() => {}, 0).unref();
+
+  expect(1).toBe(1);
+});

e2e/wrong-env/__tests__/node.js

@@ -0,0 +1,37 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @jest-environment node
+ *
+ */
+
+/* eslint-env browser */
+
+'use strict';
+
+test('use document', () => {
+  const div = document.createElement('div');
+
+  console.log(div);
+
+  expect(1).toBe(1);
+});
+
+test('use window', () => {
+  const location = window.location;
+
+  console.log(location);
+
+  expect(1).toBe(1);
+});
+
+test('use navigator', () => {
+  const userAgent = navigator.userAgent;
+
+  console.log(userAgent);
+
+  expect(1).toBe(1);
+});

e2e/wrong-env/package.json

@@ -0,0 +1,3 @@
+{
+  "jest": {}
+}

packages/jest-message-util/src/index.ts

@@ -92,6 +92,30 @@ const getRenderedCallsite = (
 
 const blankStringRegexp = /^\s*$/;
 
+function checkForCommonEnvironmentErrors(error: string) {
+  if (
+    error.includes('ReferenceError: document is not defined') ||
+    error.includes('ReferenceError: window is not defined') ||
+    error.includes('ReferenceError: navigator is not defined')
+  ) {
+    return warnAboutWrongTestEnvironment(error, 'jsdom');
+  } else if (error.includes('.unref is not a function')) {
+    return warnAboutWrongTestEnvironment(error, 'node');
+  }
+
+  return error;
+}
+
+function warnAboutWrongTestEnvironment(error: string, env: 'jsdom' | 'node') {
+  return (
+    chalk.bold.red(
+      `The error below may be caused by using the wrong test environment, see ${chalk.dim.underline(
+        'https://jestjs.io/docs/en/configuration#testenvironment-string',
+      )}.\nConsider using the "${env}" test environment.\n\n`,
+    ) + error
+  );
+}
+
 // ExecError is an error thrown outside of the test suite (not inside an `it` or
 // `before/after each` hooks). If it's thrown, none of the tests in the file
 // are executed.
@@ -126,6 +150,8 @@ export const formatExecError = (
     message = separated.message;
   }
 
+  message = checkForCommonEnvironmentErrors(message);
+
   message = indentAllLines(message, MESSAGE_INDENT);
 
   stack =
@@ -285,19 +311,21 @@ export const formatStackTrace = (
   return `${renderedCallsite}\n${stacktrace}`;
 };
 
+type FailedResults = Array<{
+  content: string;
+  result: AssertionResult;
+}>;
+
 export const formatResultsErrors = (
   testResults: Array<AssertionResult>,
   config: StackTraceConfig,
   options: StackTraceOptions,
   testPath?: Path,
 ): string | null => {
-  type FailedResults = Array<{
-    content: string;
-    result: AssertionResult;
-  }>;
-
   const failedResults: FailedResults = testResults.reduce((errors, result) => {
-    result.failureMessages.forEach(content => errors.push({content, result}));
+    result.failureMessages
+      .map(checkForCommonEnvironmentErrors)
+      .forEach(content => errors.push({content, result}));
     return errors;
   }, [] as FailedResults);