fix(config): improve emit skipped error message and ensure outDir a…

…lways `TS_JEST_OUT_DIR` (#2357)

e2e/__cases__/allow-js/with-outDir/tsconfig.json → e2e/__cases__/allow-js/tsconfig.json

@@ -2,6 +2,6 @@
   "compilerOptions": {
     "target": "es5",
     "allowJs": true,
-    "outDir": "$$ts-jest$$"
+    "outDir": "./build"
   }
 }

e2e/__tests__/allow-js.test.ts

@@ -2,21 +2,20 @@ import { allPackageSetsWithPreset, allValidPackageSets } from '../__helpers__/te
 import { configureTestCase } from '../__helpers__/test-case'
 
 describe('using babel-jest for js files', () => {
-  const testCase = configureTestCase('allow-js/with-outDir', {
+  const testCase = configureTestCase('allow-js', {
     jestConfig: { testMatch: null, testRegex: '(foo|bar)\\.spec\\.[jt]s$' },
   })
 
   testCase.runWithTemplates(allValidPackageSets, 0, (runTest, { testLabel }) => {
     it(testLabel, () => {
       const result = runTest()
       expect(result.status).toBe(0)
-      expect(result).toMatchSnapshot()
     })
   })
 })
 
-describe('using ts-jest for js files with outDir', () => {
-  const testCase = configureTestCase('allow-js/with-outDir', {
+describe('using ts-jest for js files', () => {
+  const testCase = configureTestCase('allow-js', {
     jestConfig: {
       preset: 'ts-jest/presets/js-with-ts',
       testMatch: null,
@@ -28,25 +27,6 @@ describe('using ts-jest for js files with outDir', () => {
     it(testLabel, () => {
       const result = runTest()
       expect(result.status).toBe(0)
-      expect(result).toMatchSnapshot()
-    })
-  })
-})
-
-describe('using ts-jest for js files without outDir', () => {
-  const testCase = configureTestCase('allow-js/without-outDir', {
-    jestConfig: {
-      preset: 'ts-jest/presets/js-with-ts',
-      testMatch: null,
-      testRegex: 'esm\\.spec\\.[jt]s$',
-    },
-  })
-
-  testCase.runWithTemplates(allPackageSetsWithPreset, 0, (runTest, { testLabel }) => {
-    it(testLabel, () => {
-      const result = runTest()
-      expect(result.status).toBe(0)
-      expect(result).toMatchSnapshot()
     })
   })
 })

src/compiler/__snapshots__/language-service.spec.ts.snap

@@ -1,24 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`Language service allowJs option should compile js file for allowJs true with outDir 1`] = `
-  ===[ FILE: test-allow-js.js ]===================================================
-  "use strict";
-  Object.defineProperty(exports, "__esModule", { value: true });
-  exports.default = 42;
-  //# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJmaWxlIjoidGVzdC1hbGxvdy1qcy5qcyIsIm1hcHBpbmdzIjoiOztBQUFBLGtCQUFlLEVBQUUsQ0FBQSIsIm5hbWVzIjpbXSwic291cmNlcyI6WyJ0ZXN0LWFsbG93LWpzLmpzIl0sInNvdXJjZXNDb250ZW50IjpbImV4cG9ydCBkZWZhdWx0IDQyIl0sInZlcnNpb24iOjN9
-  ===[ INLINE SOURCE MAPS ]=======================================================
-  file: test-allow-js.js
-  mappings: ;;AAAA,kBAAe,EAAE,CAAA
-  names: []
-  sources:
-    - test-allow-js.js
-  sourcesContent:
-    - export default 42
-  version: 3
-  ================================================================================
-`;
-
-exports[`Language service allowJs option should compile js file for allowJs true without outDir 1`] = `
+exports[`Language service allowJs option should compile js file for allowJs true 1`] = `
   ===[ FILE: test-allow-js.js ]===================================================
   "use strict";
   Object.defineProperty(exports, "__esModule", { value: true });

src/compiler/language-service.spec.ts

@@ -20,20 +20,11 @@ describe('Language service', () => {
     const fileName = 'test-allow-js.js'
     const source = 'export default 42'
 
-    it('should compile js file for allowJs true with outDir', () => {
-      const compiler = makeCompiler({
-        tsJestConfig: { tsconfig: { allowJs: true, outDir: '$$foo$$' } },
-      })
-
-      const compiled = compiler.compile(source, fileName)
-
-      expect(new ProcessedSource(compiled, fileName)).toMatchSnapshot()
-    })
-
-    it('should compile js file for allowJs true without outDir', () => {
+    it('should compile js file for allowJs true', () => {
       const compiler = makeCompiler({
         tsJestConfig: { tsconfig: { allowJs: true } },
       })
+
       const compiled = compiler.compile(source, fileName)
 
       expect(new ProcessedSource(compiled, fileName)).toMatchSnapshot()

src/compiler/language-service.ts

@@ -1,6 +1,6 @@
 import { LogContexts, Logger, LogLevels } from 'bs-logger'
 import { existsSync, readFileSync, writeFile } from 'fs'
-import { basename, normalize, relative, join } from 'path'
+import { basename, normalize, join } from 'path'
 import memoize = require('lodash/memoize')
 import mkdirp = require('mkdirp')
 import type * as _ts from 'typescript'
@@ -260,7 +260,7 @@ export const initializeLanguageServiceInstance = (configs: ConfigSet, logger: Lo
       }
       /* istanbul ignore next (this should never happen but is kept for security) */
       if (output.emitSkipped) {
-        throw new TypeError(`${relative(cwd, fileName)}: Emit skipped for language service`)
+        throw new Error(interpolate(Errors.CannotCompile, { file: fileName }))
       }
       // Throw an error when requiring `.d.ts` files.
       if (!output.outputFiles.length) {

src/compiler/transpiler.spec.ts

@@ -1,6 +1,5 @@
 import { makeCompiler } from '../__helpers__/fakers'
 import ProcessedSource from '../__helpers__/processed-source'
-import { TS_JEST_OUT_DIR } from '../config/config-set'
 
 describe('Transpiler', () => {
   const baseTsJestConfig = {
@@ -10,7 +9,7 @@ describe('Transpiler', () => {
   it('should compile js file for allowJs true', () => {
     const fileName = 'foo.js'
     const compiler = makeCompiler({
-      tsJestConfig: { ...baseTsJestConfig, tsconfig: { allowJs: true, outDir: TS_JEST_OUT_DIR } },
+      tsJestConfig: { ...baseTsJestConfig, tsconfig: { allowJs: true } },
     })
     const source = 'export default 42'
 

src/config/config-set.spec.ts

@@ -69,14 +69,13 @@ describe('parsedTsConfig', () => {
   })
 
   it('should override some options', () => {
-    expect(get({ tsconfig: { module: 'esnext' as any, inlineSources: false } }).options).toMatchObject({
-      module: ts.ModuleKind.CommonJS,
-      inlineSources: true,
-    })
-  })
-
-  it('should include default outDir $$ts-jest$$ when allowJs is enabled and no outDir from config', () => {
-    expect(get({ tsconfig: { allowJs: true } }).options.outDir).toBe(TS_JEST_OUT_DIR)
+    expect(get({ tsconfig: { module: 'esnext' as any, inlineSources: false, outDir: 'build' } }).options).toMatchObject(
+      {
+        module: ts.ModuleKind.CommonJS,
+        inlineSources: true,
+        outDir: TS_JEST_OUT_DIR,
+      },
+    )
   })
 
   it('should be able to read extends', () => {

src/config/config-set.ts

@@ -164,6 +164,8 @@ export class ConfigSet {
     // to clear out else it's buggy
     out: undefined,
     outFile: undefined,
+    // ensure that `LanguageService` won't pick up things from `build` folder which can lead to emit skipped error
+    outDir: TS_JEST_OUT_DIR,
     composite: undefined, // see https://github.com/TypeStrong/ts-node/pull/657/files
     declarationDir: undefined,
     declarationMap: undefined,
@@ -483,10 +485,6 @@ export class ConfigSet {
         finalOptions.allowSyntheticDefaultImports = true
       }
     }
-    // Make sure when allowJs is enabled, outDir is required to have when using allowJs: true
-    if (finalOptions.allowJs && !finalOptions.outDir) {
-      finalOptions.outDir = TS_JEST_OUT_DIR
-    }
 
     // ensure undefined are removed and other values are overridden
     for (const key of Object.keys(forcedOptions)) {

src/utils/messages.ts

@@ -16,8 +16,8 @@ export const enum Errors {
   GotUnknownFileTypeWithoutBabel = 'Got a unknown file type to compile (file: {{path}}). To fix this, in your Jest config change the `transform` key which value is `ts-jest` so that it does not match this kind of files anymore.',
   GotUnknownFileTypeWithBabel = 'Got a unknown file type to compile (file: {{path}}). To fix this, in your Jest config change the `transform` key which value is `ts-jest` so that it does not match this kind of files anymore. If you still want Babel to process it, add another entry to the `transform` option with value `babel-jest` which key matches this type of files.',
   ConfigNoModuleInterop = 'If you have issues related to imports, you should consider setting `esModuleInterop` to `true` in your TypeScript configuration file (usually `tsconfig.json`). See https://blogs.msdn.microsoft.com/typescript/2018/01/31/announcing-typescript-2-7/#easier-ecmascript-module-interoperability for more information.',
-  UnableToFindProjectRoot = 'Unable to find the root of the project where ts-jest has been installed.',
   MismatchNodeTargetMapping = 'There is a mismatch between your NodeJs version {{nodeJsVer}} and your TypeScript target {{compilationTarget}}. This might lead to some unexpected errors when running tests with `ts-jest`. To fix this, you can check https://github.com/microsoft/TypeScript/wiki/Node-Target-Mapping',
+  CannotCompile = "Unable to process '{{file}}'. Please check your tsconfig.",
 }
 
 /**