move transform types to transform package and fix babel-jest export types

Author: SimenB

packages/babel-jest/package.json

@@ -11,15 +11,16 @@
   "main": "build/index.js",
   "types": "build/index.d.ts",
   "dependencies": {
+    "@jest/transform": "^24.1.0",
     "@jest/types": "^24.1.0",
+    "@types/babel__core": "^7.0.4",
     "babel-plugin-istanbul": "^5.1.0",
     "babel-preset-jest": "^24.1.0",
     "chalk": "^2.4.2",
     "slash": "^2.0.0"
   },
   "devDependencies": {
     "@babel/core": "^7.1.0",
-    "@types/babel__core": "^7.0.4",
     "@types/slash": "^2.0.0"
   },
   "peerDependencies": {

packages/babel-jest/src/__tests__/index.ts

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import {Config, Transform} from '@jest/types';
+import {Config} from '@jest/types';
 import babelJest from '../index';
 
 //Mock data for all the tests
@@ -30,14 +30,12 @@ test(`Returns source string with inline maps when no transformOptions is passed`
     sourceString,
     'dummy_path.js',
     (mockConfig as unknown) as Config.ProjectConfig,
-  ) as Transform.TransformedSource;
+  ) as any;
   expect(typeof result).toBe('object');
   expect(result.code).toBeDefined();
   expect(result.map).toBeDefined();
   expect(result.code).toMatch('//# sourceMappingURL');
   expect(result.code).toMatch('customMultiply');
-  // @ts-ignore: it's fine if we get wrong types, the tests will fail then
   expect(result.map.sources).toEqual(['dummy_path.js']);
-  // @ts-ignore: it's fine if we get wrong types, the tests will fail then
   expect(JSON.stringify(result.map.sourcesContent)).toMatch('customMultiply');
 });

packages/babel-jest/src/index.ts

@@ -8,12 +8,13 @@
 import crypto from 'crypto';
 import fs from 'fs';
 import path from 'path';
-import {Config, Transform} from '@jest/types';
+import {Transformer} from '@jest/transform';
+import {Config} from '@jest/types';
 import {
-  transformSync as babelTransform,
   loadPartialConfig,
-  TransformOptions,
   PartialConfig,
+  TransformOptions,
+  transformSync as babelTransform,
 } from '@babel/core';
 import chalk from 'chalk';
 import slash from 'slash';
@@ -22,9 +23,14 @@ const THIS_FILE = fs.readFileSync(__filename);
 const jestPresetPath = require.resolve('babel-preset-jest');
 const babelIstanbulPlugin = require.resolve('babel-plugin-istanbul');
 
+// Make it non-optional
+type TransformerWithFactory = Transformer & {
+  createTransformer: (options?: TransformOptions) => TransformerWithFactory;
+};
+
 const createTransformer = (
   options: TransformOptions = {},
-): Transform.Transformer => {
+): TransformerWithFactory => {
   options = {
     ...options,
     // @ts-ignore: https://github.com/DefinitelyTyped/DefinitelyTyped/pull/33118
@@ -58,18 +64,15 @@ const createTransformer = (
     return babelConfig;
   }
 
-  return {
+  const transformer: TransformerWithFactory = {
     canInstrument: true,
+    createTransformer,
     getCacheKey(
-      fileData: string,
-      filename: Config.Path,
-      configString: string,
-      {
-        config,
-        instrument,
-        rootDir,
-      }: {config: Config.ProjectConfig} & Transform.CacheKeyOptions,
-    ): string {
+      fileData,
+      filename,
+      configString,
+      {config, instrument, rootDir},
+    ) {
       const babelOptions = loadBabelConfig(config.cwd, filename);
       const configPath = [
         babelOptions.config || '',
@@ -97,12 +100,7 @@ const createTransformer = (
         .update(process.env.BABEL_ENV || '')
         .digest('hex');
     },
-    process(
-      src: string,
-      filename: Config.Path,
-      config: Config.ProjectConfig,
-      transformOptions?: Transform.TransformOptions,
-    ): string | Transform.TransformedSource {
+    process(src, filename, config, transformOptions) {
       const babelOptions = {...loadBabelConfig(config.cwd, filename).options};
 
       if (transformOptions && transformOptions.instrument) {
@@ -132,13 +130,8 @@ const createTransformer = (
       return src;
     },
   };
-};
 
-const transformer = createTransformer();
-
-// FIXME: This is not part of the exported TS types. When fixed, remember to
-// move @types/babel__core to `dependencies` instead of `devDependencies`
-// (one fix is to use ESM, maybe for Jest 25?)
-transformer.createTransformer = createTransformer;
+  return transformer;
+};
 
-export = transformer;
+export = createTransformer();

packages/babel-jest/tsconfig.json

@@ -6,6 +6,7 @@
   },
   // TODO: include `babel-preset-jest` if it's ever in TS even though we don't care about its types
   "references": [
+    {"path": "../jest-transform"},
     {"path": "../jest-types"}
   ]
 }

packages/jest-transform/package.json

@@ -22,6 +22,7 @@
     "micromatch": "^3.1.10",
     "realpath-native": "^1.1.0",
     "slash": "^2.0.0",
+    "source-map": "^0.6.1",
     "write-file-atomic": "2.4.1"
   },
   "devDependencies": {

packages/jest-transform/src/ScriptTransformer.ts

@@ -8,7 +8,7 @@
 import crypto from 'crypto';
 import path from 'path';
 import vm from 'vm';
-import {Config, Transform} from '@jest/types';
+import {Config} from '@jest/types';
 import {createDirectory} from 'jest-util';
 import fs from 'graceful-fs';
 import {transformSync as babelTransform} from '@babel/core';
@@ -20,14 +20,19 @@ import stableStringify from 'fast-json-stable-stringify';
 import slash from 'slash';
 import writeFileAtomic from 'write-file-atomic';
 import {sync as realpath} from 'realpath-native';
-import {Options} from './types';
+import {
+  Options,
+  Transformer,
+  TransformedSource,
+  TransformResult,
+} from './types';
 import shouldInstrument from './shouldInstrument';
 import enhanceUnexpectedTokenMessage from './enhanceUnexpectedTokenMessage';
 
 type ProjectCache = {
   configString: string;
   ignorePatternsRegExp: RegExp | null;
-  transformedFiles: Map<string, Transform.TransformResult | string>;
+  transformedFiles: Map<string, TransformResult | string>;
 };
 
 // Use `require` to avoid TS rootDir
@@ -48,7 +53,7 @@ export default class ScriptTransformer {
   static EVAL_RESULT_VARIABLE: string;
   private _cache: ProjectCache;
   private _config: Config.ProjectConfig;
-  private _transformCache: Map<Config.Path, Transform.Transformer>;
+  private _transformCache: Map<Config.Path, Transformer>;
 
   constructor(config: Config.ProjectConfig) {
     this._config = config;
@@ -136,7 +141,7 @@ export default class ScriptTransformer {
   }
 
   private _getTransformer(filename: Config.Path) {
-    let transform: Transform.Transformer | null = null;
+    let transform: Transformer | null = null;
     if (!this._config.transform || !this._config.transform.length) {
       return null;
     }
@@ -148,7 +153,7 @@ export default class ScriptTransformer {
         return transformer;
       }
 
-      transform = require(transformPath) as Transform.Transformer;
+      transform = require(transformPath) as Transformer;
       if (typeof transform.createTransformer === 'function') {
         transform = transform.createTransformer();
       }
@@ -243,7 +248,7 @@ export default class ScriptTransformer {
       };
     }
 
-    let transformed: Transform.TransformedSource = {
+    let transformed: TransformedSource = {
       code: content,
       map: null,
     };
@@ -305,7 +310,7 @@ export default class ScriptTransformer {
     options: Options | null,
     instrument: boolean,
     fileSource?: string,
-  ): Transform.TransformResult {
+  ): TransformResult {
     const isInternalModule = !!(options && options.isInternalModule);
     const isCoreModule = !!(options && options.isCoreModule);
     const content = stripShebang(
@@ -367,10 +372,10 @@ export default class ScriptTransformer {
     filename: Config.Path,
     options: Options,
     fileSource?: string,
-  ): Transform.TransformResult | string {
+  ): TransformResult | string {
     let scriptCacheKey = null;
     let instrument = false;
-    let result: Transform.TransformResult | string | undefined = '';
+    let result: TransformResult | string | undefined = '';
 
     if (!options.isCoreModule) {
       instrument = shouldInstrument(filename, options, this._config);

packages/jest-transform/src/index.ts

@@ -7,3 +7,4 @@
 
 export {default as ScriptTransformer} from './ScriptTransformer';
 export {default as shouldInstrument} from './shouldInstrument';
+export {Transformer} from './types';

packages/jest-transform/src/types.ts

@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import {Script} from 'vm';
+import {RawSourceMap} from 'source-map';
 import {Config} from '@jest/types';
 
 export type Options = Pick<
@@ -18,3 +20,52 @@ export type Options = Pick<
   isCoreModule?: boolean;
   isInternalModule?: boolean;
 };
+
+// https://stackoverflow.com/a/48216010/1850276
+type Omit<T, K extends keyof T> = Pick<T, Exclude<keyof T, K>>;
+
+// This is fixed in a newer version, but that depends on Node 8 which is a
+// breaking change (engine warning when installing)
+interface FixedRawSourceMap extends Omit<RawSourceMap, 'version'> {
+  version: number;
+}
+
+export type TransformedSource = {
+  code: string;
+  map?: FixedRawSourceMap | string | null;
+};
+
+export type TransformResult = {
+  script: Script;
+  mapCoverage: boolean;
+  sourceMapPath: string | null;
+};
+
+export type TransformOptions = {
+  instrument: boolean;
+};
+
+export type CacheKeyOptions = {
+  config: Config.ProjectConfig;
+  instrument: boolean;
+  rootDir: string;
+};
+
+export type Transformer = {
+  canInstrument?: boolean;
+  createTransformer?: (options?: any) => Transformer;
+
+  getCacheKey: (
+    fileData: string,
+    filePath: Config.Path,
+    configStr: string,
+    options: CacheKeyOptions,
+  ) => string;
+
+  process: (
+    sourceText: string,
+    sourcePath: Config.Path,
+    config: Config.ProjectConfig,
+    options?: TransformOptions,
+  ) => string | TransformedSource;
+};

packages/jest-types/package.json

@@ -11,8 +11,5 @@
   },
   "license": "MIT",
   "main": "build/index.js",
-  "types": "build/index.d.ts",
-  "dependencies": {
-    "source-map": "^0.6.1"
-  }
+  "types": "build/index.d.ts"
 }