fix: gracefully load @babel/core or babel-core

Author: huafu

package.json

@@ -81,16 +81,17 @@
     "@babel/core": "^7.0.0-beta.54",
     "@babel/preset-env": "^7.0.0-beta.54",
     "@types/babel-core": "^6.25.5",
+    "@types/babel__core": "^7.0.1",
     "@types/es6-shim": "0.31.37",
     "@types/fs-extra": "5.0.4",
     "@types/jest": "^23.3.0",
     "@types/lodash": "^4.14.109",
     "@types/node": "10.5.5",
     "@types/react": "16.4.7",
     "@types/yargs": "^11.0.0",
+    "babel-core": "^7.0.0-0",
     "babel-jest": "^23.4.0",
     "babel-preset-jest": "^23.2.0",
-    "babel-core": "^7.0.0-0",
     "cpx": "^1.5.0",
     "cross-spawn": "latest",
     "cross-spawn-with-kill": "latest",

src/postprocess.ts

@@ -2,27 +2,32 @@
  * Postprocess step. Based on babel-jest: https://github.com/facebook/jest/blob/master/packages/babel-jest/src/index.js
  * https://github.com/facebook/jest/blob/9b157c3a7c325c3971b2aabbe4c8ab4ce0b0c56d/packages/babel-jest/src/index.js
  */
-import * as __types__babel from 'babel-core';
-import __types__istanbulPlugin from 'babel-plugin-istanbul';
-import * as __types__jestPreset from 'babel-preset-jest';
 import {
   BabelTransformOptions,
   PostProcessHook,
-  JestCacheKeyOptions,
+  TBabel,
+  TBabelPluginIstanbul,
+  TBabelPresetJest,
 } from './types';
 import { logOnce } from './utils/logger';
 import getTSJestConfig from './utils/get-ts-jest-config';
+import {
+  importBabelCore,
+  importBabelPluginIstanbul,
+  importBabelPresetJest,
+} from './utils/imports';
+import { TransformOptions } from '@babel/core';
 
-let babel: typeof __types__babel;
-let istanbulPlugin: typeof __types__istanbulPlugin;
-let jestPreset: typeof __types__jestPreset;
+let babel: TBabel;
+let istanbulPlugin: TBabelPluginIstanbul;
+let jestPreset: TBabelPresetJest;
 
 function importBabelDeps() {
   if (babel) return; // tslint:disable-line
   // we must use babel until we handle hoisting of jest.mock() internally
-  babel = require('@babel/core');
-  istanbulPlugin = require('babel-plugin-istanbul').default;
-  jestPreset = require('babel-preset-jest');
+  babel = importBabelCore();
+  istanbulPlugin = importBabelPluginIstanbul();
+  jestPreset = importBabelPresetJest();
 }
 
 // Function that takes the transpiled typescript and runs it through babel/whatever.
@@ -62,13 +67,17 @@ function createBabelTransformer(
     codeSourcemapPair: jest.TransformedSource,
     filename: string,
     config: jest.ProjectConfig,
-    transformOptions: JestCacheKeyOptions,
+    transformOptions: jest.TransformOptions,
   ): jest.TransformedSource => {
     const inputSourceMap =
       typeof codeSourcemapPair.map === 'string'
         ? JSON.parse(codeSourcemapPair.map)
         : codeSourcemapPair.map;
-    const theseOptions = { ...optionsBase, filename, inputSourceMap };
+    const theseOptions = {
+      ...optionsBase,
+      filename,
+      inputSourceMap,
+    } as TransformOptions;
     if (transformOptions && transformOptions.instrument) {
       theseOptions.auxiliaryCommentBefore = ' istanbul ignore next ';
       // Copied from jest-runtime transform.js

src/types.ts

@@ -1,5 +1,15 @@
 import { TransformOptions as BabelTransformOpts } from 'babel-core';
 
+import * as _babel from '@babel/core';
+import * as _babelEnv from '@babel/preset-env';
+import * as _babelJest from 'babel-preset-jest';
+import _babelIstanbul from 'babel-plugin-istanbul';
+
+export type TBabel = typeof _babel;
+export type TBabelPluginIstanbul = typeof _babelIstanbul;
+export type TBabelPresetEnv = typeof _babelEnv;
+export type TBabelPresetJest = typeof _babelJest;
+
 export interface JestCacheKeyOptions {
   rootDir: string;
   instrument: boolean;

src/utils/imports.ts

@@ -0,0 +1,57 @@
+import {
+  TBabel,
+  TBabelPresetEnv,
+  TBabelPluginIstanbul,
+  TBabelPresetJest,
+} from '../types';
+
+export function importBabelCore(): TBabel {
+  const mod = tryRequire('@babel/core') || tryRequire('babel-core');
+  if (!mod) {
+    throw new Error(
+      `[ts-jest] You must install the '@babel/core' or 'babel-core'` +
+        ` package (depending on the version you want to use).`,
+    );
+  }
+  return mod;
+}
+
+export function importBabelPresetEnv(): TBabelPresetEnv {
+  const mod = tryRequire('@babel/preset-env') || tryRequire('babel-preset-env');
+  if (!mod) {
+    throw new Error( // babel-jest has the env preset as a dep
+      `[ts-jest] You must install the 'babel-jest' package if you're using babel.`,
+    );
+  }
+  return mod;
+}
+
+export function importBabelPresetJest(): TBabelPresetJest {
+  const mod = tryRequire('babel-preset-jest');
+  if (!mod) {
+    throw new Error( // babel-jest has the jest preset as a dep
+      `[ts-jest] You must install the 'babel-jest' package if you're using babel.`,
+    );
+  }
+  return mod;
+}
+
+export function importBabelPluginIstanbul(): TBabelPluginIstanbul {
+  const mod = tryRequire('babel-plugin-istanbul');
+  if (!mod) {
+    throw new Error( // babel-jest has the istanbul plugin as a dep
+      `[ts-jest] You must install the 'babel-jest' package if you're using babel.`,
+    );
+  }
+  return mod.default;
+}
+
+function tryRequire<T = any>(packageName: string): T | void {
+  let mod: T;
+  try {
+    mod = require(packageName);
+  } catch (err) {
+    if (err.code !== 'ENOENT') throw err; // tslint:disable-line
+  }
+  return mod;
+}

yarn.lock

@@ -515,6 +515,14 @@
     lodash "^4.17.5"
     to-fast-properties "^2.0.0"
 
+"@babel/types@^7.0.0-beta.54":
+  version "7.0.0-beta.55"
+  resolved "https://registry.yarnpkg.com/@babel/types/-/types-7.0.0-beta.55.tgz#7755c9d2e58315a64f05d8cf3322379be16d9199"
+  dependencies:
+    esutils "^2.0.2"
+    lodash "^4.17.10"
+    to-fast-properties "^2.0.0"
+
 "@samverschueren/stream-to-observable@^0.3.0":
   version "0.3.0"
   resolved "https://registry.yarnpkg.com/@samverschueren/stream-to-observable/-/stream-to-observable-0.3.0.tgz#ecdf48d532c58ea477acfcab80348424f8d0662f"
@@ -554,6 +562,12 @@
   version "7.0.4"
   resolved "https://registry.yarnpkg.com/@types/babel-types/-/babel-types-7.0.4.tgz#bfd5b0d0d1ba13e351dff65b6e52783b816826c8"
 
+"@types/babel__core@^7.0.1":
+  version "7.0.1"
+  resolved "https://registry.yarnpkg.com/@types/babel__core/-/babel__core-7.0.1.tgz#8b608a1c55cb4c752352cc6c78f7beb61a3fd51f"
+  dependencies:
+    "@babel/types" "^7.0.0-beta.54"
+
 "@types/babylon@*":
   version "6.16.3"
   resolved "https://registry.yarnpkg.com/@types/babylon/-/babylon-6.16.3.tgz#c2937813a89fcb5e79a00062fc4a8b143e7237bb"
@@ -3979,22 +3993,22 @@ rc@^1.1.7:
     minimist "^1.2.0"
     strip-json-comments "~2.0.1"
 
-react-is@^16.4.1:
-  version "16.4.1"
-  resolved "https://registry.yarnpkg.com/react-is/-/react-is-16.4.1.tgz#d624c4650d2c65dbd52c72622bbf389435d9776e"
+react-is@^16.4.2:
+  version "16.4.2"
+  resolved "https://registry.yarnpkg.com/react-is/-/react-is-16.4.2.tgz#84891b56c2b6d9efdee577cc83501dfc5ecead88"
 
-react-test-renderer@16.4.1:
-  version "16.4.1"
-  resolved "https://registry.yarnpkg.com/react-test-renderer/-/react-test-renderer-16.4.1.tgz#f2fb30c2c7b517db6e5b10ed20bb6b0a7ccd8d70"
+react-test-renderer@16.4.2:
+  version "16.4.2"
+  resolved "https://registry.yarnpkg.com/react-test-renderer/-/react-test-renderer-16.4.2.tgz#4e03eca9359bb3210d4373f7547d1364218ef74e"
   dependencies:
     fbjs "^0.8.16"
     object-assign "^4.1.1"
     prop-types "^15.6.0"
-    react-is "^16.4.1"
+    react-is "^16.4.2"
 
-react@16.4.1:
-  version "16.4.1"
-  resolved "https://registry.yarnpkg.com/react/-/react-16.4.1.tgz#de51ba5764b5dbcd1f9079037b862bd26b82fe32"
+react@16.4.2:
+  version "16.4.2"
+  resolved "https://registry.yarnpkg.com/react/-/react-16.4.2.tgz#2cd90154e3a9d9dd8da2991149fdca3c260e129f"
   dependencies:
     fbjs "^0.8.16"
     loose-envify "^1.1.0"