Deprecate jest/preprocessor.js

Summary: Changelog: [General][Deprecated] Deprecate the use of `react-native/jest/preprocessor.js` by external projects The supported method of using Jest in React Native projects is using the [Jest preset](https://jestjs.io/docs/tutorial-react-native) shipped as part of the `react-native` package. Some projects are directly using `preprocessor.js` which is part of the testing setup for the React Native repo itself. In a future release of React Native, we will stop publishing this file to npm and require projects to switch to the supported preset (or a custom Jest config if necessary). Reviewed By: GijsWeterings Differential Revision: D34820086 fbshipit-source-id: 197c33726639e66c6916a244117252e6af11f2f6
2026-09-28 05:13:06 +08:00 · 2022-03-14 07:40:05 -07:00
parent 5ea50fd549
commit c1e9aa9a27
3 changed files with 146 additions and 106 deletions
@@ -13,7 +13,7 @@ module.exports = {
  transform: {
    '^.+\\.(bmp|gif|jpg|jpeg|mp4|png|psd|svg|webp)$':
      '<rootDir>/jest/assetFileTransformer.js',
-    '.*': './jest/preprocessor.js',
+    '.*': './jest/preprocessor_DO_NOT_USE.js',
  },
  setupFiles: ['./jest/setup.js'],
  timers: 'fake',
@@ -12,111 +12,29 @@

 'use strict';

-const babelRegisterOnly = require('metro-babel-register');
-const createCacheKeyFunction =
-  require('@jest/create-cache-key-function').default;
+// NOTE: Avoiding using a package like 'chalk' here, for simplicity
+const YELLOW = process.stderr.isTTY ? '\u001b[33m' : '';
+const BOLD = process.stderr.isTTY ? '\u001b[1m' : '';
+const RESET = process.stderr.isTTY ? '\u001b[0m' : '';
+const UNDERLINE = process.stderr.isTTY ? '\u001b[4m' : '';

-const {transformSync: babelTransformSync} = require('@babel/core');
-const generate = require('@babel/generator').default;
-
-const nodeFiles = new RegExp(
-  [
-    '/metro(?:-[^/]*)?/', // metro, metro-core, metro-source-map, metro-etc.
-  ].join('|'),
+console.warn(
+  '\n' +
+    YELLOW +
+    BOLD +
+    'react-native/jest/preprocessor.js' +
+    RESET +
+    YELLOW +
+    ' is deprecated and will be removed.\n' +
+    'Use "preset": "react-native" in your Jest config instead.\n' +
+    'See ' +
+    UNDERLINE +
+    'https://jestjs.io/docs/tutorial-react-native' +
+    RESET +
+    YELLOW +
+    ' for more setup instructions.' +
+    RESET +
+    '\n',
 );
-const nodeOptions = babelRegisterOnly.config([nodeFiles]);

-babelRegisterOnly([]);
-
-const transformer = require('metro-react-native-babel-transformer');
-module.exports = {
-  process(src /*: string */, file /*: string */) /*: string */ {
-    if (nodeFiles.test(file)) {
-      // node specific transforms only
-      return babelTransformSync(src, {
-        filename: file,
-        sourceType: 'script',
-        ...nodeOptions,
-        ast: false,
-      }).code;
-    }
-
-    const {ast} = transformer.transform({
-      filename: file,
-      options: {
-        ast: true, // needed for open source (?) https://github.com/facebook/react-native/commit/f8d6b97140cffe8d18b2558f94570c8d1b410d5c#r28647044
-        dev: true,
-        enableBabelRuntime: false,
-        experimentalImportSupport: false,
-        globalPrefix: '',
-        hot: false,
-        inlineRequires: true,
-        minify: false,
-        platform: '',
-        projectRoot: '',
-        publicPath: '/assets',
-        retainLines: true,
-        sourceType: 'unambiguous', // b7 required. detects module vs script mode
-      },
-      src,
-      plugins: [
-        [require('@babel/plugin-transform-block-scoping')],
-        // the flow strip types plugin must go BEFORE class properties!
-        // there'll be a test case that fails if you don't.
-        [require('@babel/plugin-transform-flow-strip-types')],
-        [
-          require('@babel/plugin-proposal-class-properties'),
-          // use `this.foo = bar` instead of `this.defineProperty('foo', ...)`
-          {loose: true},
-        ],
-        [require('@babel/plugin-transform-computed-properties')],
-        [require('@babel/plugin-transform-destructuring')],
-        [require('@babel/plugin-transform-function-name')],
-        [require('@babel/plugin-transform-literals')],
-        [require('@babel/plugin-transform-parameters')],
-        [require('@babel/plugin-transform-shorthand-properties')],
-        [require('@babel/plugin-transform-react-jsx')],
-        [require('@babel/plugin-transform-regenerator')],
-        [require('@babel/plugin-transform-sticky-regex')],
-        [require('@babel/plugin-transform-unicode-regex')],
-        [
-          require('@babel/plugin-transform-modules-commonjs'),
-          {strict: false, allowTopLevelThis: true},
-        ],
-        [require('@babel/plugin-transform-classes')],
-        [require('@babel/plugin-transform-arrow-functions')],
-        [require('@babel/plugin-transform-spread')],
-        [require('@babel/plugin-proposal-object-rest-spread')],
-        [
-          require('@babel/plugin-transform-template-literals'),
-          {loose: true}, // dont 'a'.concat('b'), just use 'a'+'b'
-        ],
-        [require('@babel/plugin-transform-exponentiation-operator')],
-        [require('@babel/plugin-transform-for-of'), {loose: true}],
-        [require('@babel/plugin-transform-react-display-name')],
-        [require('@babel/plugin-transform-react-jsx-source')],
-      ],
-    });
-
-    return generate(
-      ast,
-      // $FlowFixMe[prop-missing] Error found when improving flow typing for libs
-      {
-        code: true,
-        comments: false,
-        compact: false,
-        filename: file,
-        retainLines: true,
-        sourceFileName: file,
-        sourceMaps: true,
-      },
-      src,
-    ).code;
-  },
-
-  getCacheKey: (createCacheKeyFunction([
-    __filename,
-    require.resolve('metro-react-native-babel-transformer'),
-    require.resolve('@babel/core/package.json'),
-  ]) /*: any */),
-};
+module.exports = require('./preprocessor_DO_NOT_USE');
@@ -0,0 +1,122 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @flow
+ */
+
+/* eslint-env node */
+
+'use strict';
+
+const babelRegisterOnly = require('metro-babel-register');
+const createCacheKeyFunction =
+  require('@jest/create-cache-key-function').default;
+
+const {transformSync: babelTransformSync} = require('@babel/core');
+const generate = require('@babel/generator').default;
+
+const nodeFiles = new RegExp(
+  [
+    '/metro(?:-[^/]*)?/', // metro, metro-core, metro-source-map, metro-etc.
+  ].join('|'),
+);
+const nodeOptions = babelRegisterOnly.config([nodeFiles]);
+
+babelRegisterOnly([]);
+
+const transformer = require('metro-react-native-babel-transformer');
+module.exports = {
+  process(src /*: string */, file /*: string */) /*: string */ {
+    if (nodeFiles.test(file)) {
+      // node specific transforms only
+      return babelTransformSync(src, {
+        filename: file,
+        sourceType: 'script',
+        ...nodeOptions,
+        ast: false,
+      }).code;
+    }
+
+    const {ast} = transformer.transform({
+      filename: file,
+      options: {
+        ast: true, // needed for open source (?) https://github.com/facebook/react-native/commit/f8d6b97140cffe8d18b2558f94570c8d1b410d5c#r28647044
+        dev: true,
+        enableBabelRuntime: false,
+        experimentalImportSupport: false,
+        globalPrefix: '',
+        hot: false,
+        inlineRequires: true,
+        minify: false,
+        platform: '',
+        projectRoot: '',
+        publicPath: '/assets',
+        retainLines: true,
+        sourceType: 'unambiguous', // b7 required. detects module vs script mode
+      },
+      src,
+      plugins: [
+        [require('@babel/plugin-transform-block-scoping')],
+        // the flow strip types plugin must go BEFORE class properties!
+        // there'll be a test case that fails if you don't.
+        [require('@babel/plugin-transform-flow-strip-types')],
+        [
+          require('@babel/plugin-proposal-class-properties'),
+          // use `this.foo = bar` instead of `this.defineProperty('foo', ...)`
+          {loose: true},
+        ],
+        [require('@babel/plugin-transform-computed-properties')],
+        [require('@babel/plugin-transform-destructuring')],
+        [require('@babel/plugin-transform-function-name')],
+        [require('@babel/plugin-transform-literals')],
+        [require('@babel/plugin-transform-parameters')],
+        [require('@babel/plugin-transform-shorthand-properties')],
+        [require('@babel/plugin-transform-react-jsx')],
+        [require('@babel/plugin-transform-regenerator')],
+        [require('@babel/plugin-transform-sticky-regex')],
+        [require('@babel/plugin-transform-unicode-regex')],
+        [
+          require('@babel/plugin-transform-modules-commonjs'),
+          {strict: false, allowTopLevelThis: true},
+        ],
+        [require('@babel/plugin-transform-classes')],
+        [require('@babel/plugin-transform-arrow-functions')],
+        [require('@babel/plugin-transform-spread')],
+        [require('@babel/plugin-proposal-object-rest-spread')],
+        [
+          require('@babel/plugin-transform-template-literals'),
+          {loose: true}, // dont 'a'.concat('b'), just use 'a'+'b'
+        ],
+        [require('@babel/plugin-transform-exponentiation-operator')],
+        [require('@babel/plugin-transform-for-of'), {loose: true}],
+        [require('@babel/plugin-transform-react-display-name')],
+        [require('@babel/plugin-transform-react-jsx-source')],
+      ],
+    });
+
+    return generate(
+      ast,
+      // $FlowFixMe[prop-missing] Error found when improving flow typing for libs
+      {
+        code: true,
+        comments: false,
+        compact: false,
+        filename: file,
+        retainLines: true,
+        sourceFileName: file,
+        sourceMaps: true,
+      },
+      src,
+    ).code;
+  },
+
+  getCacheKey: (createCacheKeyFunction([
+    __filename,
+    require.resolve('metro-react-native-babel-transformer'),
+    require.resolve('@babel/core/package.json'),
+  ]) /*: any */),
+};