Resolve dynamic dependencies correctly when a mapping exists (#9303)

Author: MrJohz

CHANGELOG.md

@@ -63,6 +63,7 @@
 - `[jest-reporters]` Make node-notifier an optional dependency ([#8918](https://github.com/facebook/jest/pull/8918))
 - `[jest-reporters]` Make all arguments to methods on `BaseReporter` optional ([#9159](https://github.com/facebook/jest/pull/9159))
 - `[jest-resolve]`: Set MODULE_NOT_FOUND as error code when module is not resolved from paths ([#8487](https://github.com/facebook/jest/pull/8487))
+- `[jest-resolve-dependencies]` Handle dynamic dependencies correctly even when using module maps ([#9303](https://github.com/facebook/jest/pull/9303))
 - `[jest-snapshot]` Remove only the added newlines in multiline snapshots ([#8859](https://github.com/facebook/jest/pull/8859))
 - `[jest-snapshot]` Distinguish empty string from external snapshot not written ([#8880](https://github.com/facebook/jest/pull/8880))
 - `[jest-snapshot]` [**BREAKING**] Distinguish empty string from internal snapshot not written ([#8898](https://github.com/facebook/jest/pull/8898))

e2e/__tests__/dynamicRequireDependencies.ts

@@ -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.
+ */
+
+import * as path from 'path';
+import {json as runWithJson} from '../runJest';
+
+const dir = path.resolve(__dirname, '../dynamic-require-dependencies');
+
+test('successfully runs tests with dynamic dependencies', () => {
+  const {json} = runWithJson(dir, ['--findRelatedTests', 'dynamicRequire.js']);
+  expect(json.success).toBe(true);
+  expect(json.numTotalTests).toBe(2);
+});

e2e/dynamic-require-dependencies/__tests__/dynamicRequire.test.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.
+ */
+
+test('loading a file with a dynamic local require should work', () => {
+  const {withStandardResolution} = require('../dynamicRequire');
+  expect(withStandardResolution()).toBe(1);
+});
+
+test('loading a file with a dynamic require and custom resolve should work', () => {
+  const {withCustomResolution} = require('../dynamicRequire');
+  expect(withCustomResolution()).toBe(1);
+});

e2e/dynamic-require-dependencies/dynamicRequire.js

@@ -0,0 +1,13 @@
+/**
+ * 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.
+ */
+
+const dynamicModuleName = 'source';
+
+module.exports.withStandardResolution = () =>
+  require(`./${dynamicModuleName}.js`);
+module.exports.withCustomResolution = () =>
+  require(`$asdf/${dynamicModuleName}.js`);

e2e/dynamic-require-dependencies/package.json

@@ -0,0 +1,7 @@
+{
+  "jest": {
+    "moduleNameMapper": {
+      "^\\$asdf/(.*)$": "<rootDir>/$1"
+    }
+  }
+}

e2e/dynamic-require-dependencies/source.js

@@ -0,0 +1,8 @@
+/**
+ * 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.
+ */
+
+module.exports = 1;

packages/jest-resolve-dependencies/src/__tests__/dependency_resolver.test.ts

@@ -5,6 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import Resolver = require('jest-resolve');
 import {tmpdir} from 'os';
 import * as path from 'path';
 import {Config} from '@jest/types';
@@ -15,6 +16,7 @@ import DependencyResolver from '../index';
 
 const maxWorkers = 1;
 let dependencyResolver: DependencyResolver;
+let runtimeContextResolver: Resolver;
 let Runtime;
 let config: Config.ProjectConfig;
 const cases: Record<string, jest.Mock> = {
@@ -29,11 +31,13 @@ beforeEach(() => {
   config = makeProjectConfig({
     cacheDirectory: path.resolve(tmpdir(), 'jest-resolve-dependencies-test'),
     moduleDirectories: ['node_modules'],
+    moduleNameMapper: [['^\\$asdf/(.*)$', '<rootDir>/$1']],
     rootDir: '.',
     roots: ['./packages/jest-resolve-dependencies'],
   });
   return Runtime.createContext(config, {maxWorkers, watchman: false}).then(
     (runtimeContext: any) => {
+      runtimeContextResolver = runtimeContext.resolver;
       dependencyResolver = new DependencyResolver(
         runtimeContext.resolver,
         runtimeContext.hasteFS,
@@ -106,3 +110,18 @@ test('resolves inverse dependencies from available snapshot', () => {
     ]),
   );
 });
+
+test('resolves dependencies correctly when dependency resolution fails', () => {
+  jest.spyOn(runtimeContextResolver, 'resolveModule').mockImplementation(() => {
+    throw new Error('resolveModule has failed');
+  });
+  jest.spyOn(runtimeContextResolver, 'getMockModule').mockImplementation(() => {
+    throw new Error('getMockModule has failed');
+  });
+
+  const resolved = dependencyResolver.resolve(
+    path.resolve(__dirname, '__fixtures__', 'file.test.js'),
+  );
+
+  expect(resolved).toEqual([]);
+});

packages/jest-resolve-dependencies/src/index.ts

@@ -58,8 +58,12 @@ class DependencyResolver {
           dependency,
           options,
         );
-      } catch (e) {
-        resolvedDependency = this._resolver.getMockModule(file, dependency);
+      } catch {
+        try {
+          resolvedDependency = this._resolver.getMockModule(file, dependency);
+        } catch {
+          // leave resolvedDependency as undefined if nothing can be found
+        }
       }
 
       if (resolvedDependency) {