perf(compiler): use moduleResolutionCache for Language Service's resolveModuleNames

src/__helpers__/fakers.ts

@@ -68,13 +68,6 @@ export function createConfigSet({
   resolve?: ((path: string) => string) | null
   [key: string]: any
 } = {}): ConfigSet {
-  const defaultTestRegex = ['(/__tests__/.*|(\\\\.|/)(test|spec))\\\\.[jt]sx?$']
-  const defaultTestMatch = ['**/__tests__/**/*.[jt]s?(x)', '**/?(*.)+(spec|test).[jt]s?(x)']
-  jestConfig = {
-    ...jestConfig,
-    testMatch: jestConfig?.testMatch ? [...jestConfig.testMatch, ...defaultTestMatch] : defaultTestMatch,
-    testRegex: jestConfig?.testRegex ? [...defaultTestRegex, ...jestConfig.testRegex] : defaultTestRegex,
-  }
   const cs = new ConfigSet(getJestConfig(jestConfig, tsJestConfig), parentConfig)
   if (resolve) {
     cs.resolvePath = resolve
@@ -101,6 +94,13 @@ export function makeCompiler({
     ...(tsJestConfig.diagnostics as any),
     pretty: false,
   }
+  const defaultTestRegex = ['(/__tests__/.*|(\\\\.|/)(test|spec))\\\\.[jt]sx?$']
+  const defaultTestMatch = ['**/__tests__/**/*.[jt]s?(x)', '**/?(*.)+(spec|test).[jt]s?(x)']
+  jestConfig = {
+    ...jestConfig,
+    testMatch: jestConfig?.testMatch ? [...jestConfig.testMatch, ...defaultTestMatch] : defaultTestMatch,
+    testRegex: jestConfig?.testRegex ? [...defaultTestRegex, ...jestConfig.testRegex] : defaultTestRegex,
+  }
   const cs = createConfigSet({ jestConfig, tsJestConfig, parentConfig, resolve: null })
 
   return createCompilerInstance(cs)

src/compiler/language-service.spec.ts

@@ -10,6 +10,8 @@ import ProcessedSource from '../__helpers__/processed-source'
 const logTarget = logTargetMock()
 
 describe('Language service', () => {
+  const baseTsJestConfig = { tsConfig: require.resolve('../../tsconfig.spec.json') }
+
   beforeEach(() => {
     logTarget.clear()
   })
@@ -107,10 +109,26 @@ describe('Language service', () => {
     })
   })
 
+  describe('module resolution', () => {
+    it(`should use moduleResolutionCache`, () => {
+      jest.unmock('typescript')
+      const ts = require('typescript')
+      const moduleResolutionCacheMock = (ts.createModuleResolutionCache = jest.fn().mockImplementation(() => {}))
+
+      makeCompiler({
+        tsJestConfig: baseTsJestConfig,
+      })
+
+      expect(moduleResolutionCacheMock).toHaveBeenCalled()
+      expect(moduleResolutionCacheMock.mock.calls[0].length).toBe(3)
+
+      moduleResolutionCacheMock.mockRestore()
+    })
+  })
+
   describe('diagnostics', () => {
     const importedFileName = require.resolve('../__mocks__/thing.ts')
     const importedFileContent = readFileSync(importedFileName, 'utf-8')
-    const baseTsJestConfig = { tsConfig: require.resolve('../../tsconfig.spec.json') }
 
     it(`should report diagnostics for imported modules as well as test files which use imported modules with cache`, async () => {
       const testFileName = require.resolve('../__mocks__/thing1.spec.ts')

src/compiler/language-service.ts

@@ -80,12 +80,19 @@ export const initializeLanguageServiceInstance = (configs: ConfigSet, logger: Lo
     realpath: ts.sys.realpath && memoize(ts.sys.realpath),
     getDirectories: memoize(ts.sys.getDirectories),
   }
+  const moduleResolutionCache = ts.createModuleResolutionCache(cwd, (x) => x, options)
   function resolveModuleNames(moduleNames: string[], containingFile: string): (_ts.ResolvedModuleFull | undefined)[] {
     const normalizedContainingFile = normalize(containingFile)
     const currentResolvedModules = memoryCache.resolvedModules.get(normalizedContainingFile) ?? []
 
     return moduleNames.map((moduleName) => {
-      const resolveModuleName = ts.resolveModuleName(moduleName, containingFile, options, moduleResolutionHost)
+      const resolveModuleName = ts.resolveModuleName(
+        moduleName,
+        containingFile,
+        options,
+        moduleResolutionHost,
+        moduleResolutionCache,
+      )
       const resolvedModule = resolveModuleName.resolvedModule
       if (configs.isTestFile(normalizedContainingFile) && resolvedModule) {
         const normalizedResolvedFileName = normalize(resolvedModule.resolvedFileName)

src/config/__snapshots__/config-set.spec.ts.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`cacheKey should be a string 1`] = `"{\\"digest\\":\\"a0d51ca854194df8191d0e65c0ca4730f510f332\\",\\"jest\\":{\\"__backported\\":true,\\"globals\\":{},\\"testMatch\\":[\\"**/__tests__/**/*.[jt]s?(x)\\",\\"**/?(*.)+(spec|test).[jt]s?(x)\\"],\\"testRegex\\":[\\"(/__tests__/.*|(\\\\\\\\\\\\\\\\.|/)(test|spec))\\\\\\\\\\\\\\\\.[jt]sx?$\\"]},\\"projectDepVersions\\":{\\"dev\\":\\"1.2.5\\",\\"opt\\":\\"1.2.3\\",\\"peer\\":\\"1.2.4\\",\\"std\\":\\"1.2.6\\"},\\"transformers\\":[\\"hoisting-jest-mock@1\\"],\\"tsJest\\":{\\"compiler\\":\\"typescript\\",\\"diagnostics\\":{\\"ignoreCodes\\":[6059,18002,18003],\\"pretty\\":true,\\"throws\\":true},\\"isolatedModules\\":false,\\"packageJson\\":{\\"kind\\":\\"file\\"},\\"transformers\\":[]},\\"tsconfig\\":{\\"declaration\\":false,\\"inlineSourceMap\\":false,\\"inlineSources\\":true,\\"module\\":1,\\"noEmit\\":false,\\"removeComments\\":false,\\"sourceMap\\":true,\\"target\\":1}}"`;
+exports[`cacheKey should be a string 1`] = `"{\\"digest\\":\\"a0d51ca854194df8191d0e65c0ca4730f510f332\\",\\"jest\\":{\\"__backported\\":true,\\"globals\\":{}},\\"projectDepVersions\\":{\\"dev\\":\\"1.2.5\\",\\"opt\\":\\"1.2.3\\",\\"peer\\":\\"1.2.4\\",\\"std\\":\\"1.2.6\\"},\\"transformers\\":[\\"hoisting-jest-mock@1\\"],\\"tsJest\\":{\\"compiler\\":\\"typescript\\",\\"diagnostics\\":{\\"ignoreCodes\\":[6059,18002,18003],\\"pretty\\":true,\\"throws\\":true},\\"isolatedModules\\":false,\\"packageJson\\":{\\"kind\\":\\"file\\"},\\"transformers\\":[]},\\"tsconfig\\":{\\"declaration\\":false,\\"inlineSourceMap\\":false,\\"inlineSources\\":true,\\"module\\":1,\\"noEmit\\":false,\\"removeComments\\":false,\\"sourceMap\\":true,\\"target\\":1}}"`;
 
 exports[`isTestFile should return a boolean value whether the file matches test pattern 1`] = `true`;
 
@@ -18,41 +18,20 @@ Object {
       "__parent": true,
     },
   },
-  "testMatch": Array [
-    "**/__tests__/**/*.[jt]s?(x)",
-    "**/?(*.)+(spec|test).[jt]s?(x)",
-  ],
-  "testRegex": Array [
-    "(/__tests__/.*|(\\\\\\\\.|/)(test|spec))\\\\\\\\.[jt]sx?$",
-  ],
 }
 `;
 
 exports[`jest should merge parent config if any with globals is undefined 1`] = `
 Object {
   "__backported": true,
   "globals": undefined,
-  "testMatch": Array [
-    "**/__tests__/**/*.[jt]s?(x)",
-    "**/?(*.)+(spec|test).[jt]s?(x)",
-  ],
-  "testRegex": Array [
-    "(/__tests__/.*|(\\\\\\\\.|/)(test|spec))\\\\\\\\.[jt]sx?$",
-  ],
 }
 `;
 
 exports[`jest should return correct config and go thru backports 1`] = `
 Object {
   "__backported": true,
   "globals": Object {},
-  "testMatch": Array [
-    "**/__tests__/**/*.[jt]s?(x)",
-    "**/?(*.)+(spec|test).[jt]s?(x)",
-  ],
-  "testRegex": Array [
-    "(/__tests__/.*|(\\\\\\\\.|/)(test|spec))\\\\\\\\.[jt]sx?$",
-  ],
 }
 `;
 
@@ -63,13 +42,6 @@ Object {
   "jest": Object {
     "__backported": true,
     "globals": Object {},
-    "testMatch": Array [
-      "**/__tests__/**/*.[jt]s?(x)",
-      "**/?(*.)+(spec|test).[jt]s?(x)",
-    ],
-    "testRegex": Array [
-      "(/__tests__/.*|(\\\\\\\\.|/)(test|spec))\\\\\\\\.[jt]sx?$",
-    ],
   },
   "projectDepVersions": Object {
     "some-module": "1.2.3",

src/config/config-set.spec.ts

@@ -15,7 +15,9 @@ import { getPackageVersion } from '../util/get-package-version'
 import { normalizeSlashes } from '../util/normalize-slashes'
 import { mocked } from '../util/testing'
 
-import { ConfigSet, IGNORE_DIAGNOSTIC_CODES, MATCH_NOTHING, TS_JEST_OUT_DIR } from './config-set'
+import { IGNORE_DIAGNOSTIC_CODES, MATCH_NOTHING, TS_JEST_OUT_DIR } from './config-set'
+// eslint-disable-next-line no-duplicate-imports
+import type { ConfigSet } from './config-set'
 
 jest.mock('../util/backports')
 jest.mock('../index')
@@ -795,6 +797,7 @@ describe('readTsConfig', () => {
       { jestConfig: { rootDir: '/root', cwd: '/cwd' } as any },
     ])('toggle warning message for users who are using ts-jest with babel or without babel', (config) => {
       const shouldAction = config.tsJestConfig?.babelConfig ? `shouldn't` : 'should'
+
       beforeEach(() => {
         logTarget.clear()
         cs = createConfigSet(config)
@@ -974,6 +977,10 @@ describe('shouldReportDiagnostic', () => {
 describe('tsCompiler', () => {
   it('should be a compiler object', () => {
     const cs = createConfigSet({
+      jestConfig: {
+        testRegex: [],
+        testMatch: [],
+      },
       tsJestConfig: { tsConfig: false } as any,
     })
     const compiler = cs.tsCompiler

src/config/config-set.ts

@@ -210,7 +210,6 @@ export class ConfigSet {
          */
         pattern instanceof RegExp || typeof pattern === 'string',
     )
-    /* istanbul ignore next */
     if (!matchablePatterns.length) {
       matchablePatterns.push(...DEFAULT_JEST_TEST_MATCH)
     }