fix(compiler): exclude files in outDir from compiler source files (#2376)

Closes #2350
Closes #2374

Author: ahnpnl

src/compiler/language-service.ts

@@ -5,7 +5,7 @@ import memoize = require('lodash/memoize')
 import mkdirp = require('mkdirp')
 import type * as _ts from 'typescript'
 
-import type { ConfigSet } from '../config/config-set'
+import { ConfigSet, TS_JEST_OUT_DIR } from '../config/config-set'
 import { LINE_FEED } from '../constants'
 import type { CompilerInstance, SourceOutput } from '../types'
 import { Errors, interpolate } from '../utils/messages'
@@ -75,7 +75,10 @@ export const initializeLanguageServiceInstance = (configs: ConfigSet, logger: Lo
   }
   // Initialize memory cache for typescript compiler
   configs.parsedTsConfig.fileNames
-    .filter((fileName: string) => !configs.isTestFile(fileName))
+    .filter(
+      (fileName: string) =>
+        !configs.isTestFile(fileName) && !fileName.includes(configs.parsedTsConfig.options.outDir ?? TS_JEST_OUT_DIR),
+    )
     .forEach((fileName: string) => {
       memoryCache.files.set(fileName, {
         version: 0,

src/config/config-set.spec.ts

@@ -12,7 +12,7 @@ import { getPackageVersion } from '../utils/get-package-version'
 import { normalizeSlashes } from '../utils/normalize-slashes'
 import { mocked } from '../utils/testing'
 
-import { ConfigSet, MY_DIGEST, TS_JEST_OUT_DIR } from './config-set'
+import { ConfigSet, MY_DIGEST } from './config-set'
 
 jest.mock('../utils/backports')
 jest.mock('../index')
@@ -73,7 +73,6 @@ describe('parsedTsConfig', () => {
       {
         module: ts.ModuleKind.CommonJS,
         inlineSources: true,
-        outDir: TS_JEST_OUT_DIR,
       },
     )
   })

src/config/config-set.ts

@@ -164,8 +164,6 @@ 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,
@@ -485,6 +483,10 @@ 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)) {