Uses existing instance if config file is same as already built solution

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+## v8.0.4
+* [Uses existing instance if config file is same as already built solution](https://github.com/TypeStrong/ts-loader/pull/1177) - thanks @sheetalkamat
+
 ## v8.0.3
 * [Fix the wrong instance caching when using `appendTsSuffixTo` and `appendTsxSuffixTo` together](https://github.com/TypeStrong/ts-loader/pull/1170) - thanks @meowtec
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ts-loader",
-  "version": "8.0.3",
+  "version": "8.0.4",
   "description": "TypeScript loader for webpack",
   "main": "index.js",
   "types": "dist",

src/after-compile.ts

@@ -6,6 +6,7 @@ import * as constants from './constants';
 import { getEmitFromWatchHost, getEmitOutput } from './instances';
 import {
   FilePathKey,
+  LoaderOptions,
   TSFiles,
   TSInstance,
   WebpackModule,
@@ -17,6 +18,7 @@ import {
   formatErrors,
   isReferencedFile,
   populateReverseDependencyGraph,
+  tsLoaderSource,
 } from './utils';
 
 export function makeAfterCompile(
@@ -41,7 +43,7 @@ export function makeAfterCompile(
       callback();
       return;
     }
-    removeCompilationTSLoaderErrors(compilation);
+    removeCompilationTSLoaderErrors(compilation, instance.loaderOptions);
 
     provideCompilerOptionDiagnosticErrorsToWebpack(
       getCompilerOptionDiagnostics,
@@ -235,7 +237,7 @@ function provideErrorsToWebpack(
     const associatedModules = modules.get(instance.filePathKeyMapper(fileName));
     if (associatedModules !== undefined) {
       associatedModules.forEach(module => {
-        removeModuleTSLoaderError(module);
+        removeModuleTSLoaderError(module, loaderOptions);
 
         // append errors
         const formattedErrors = formatErrors(
@@ -299,7 +301,7 @@ function provideSolutionErrorsToWebpack(
     const associatedModules = modules.get(filePath);
     if (associatedModules !== undefined) {
       associatedModules.forEach(module => {
-        removeModuleTSLoaderError(module);
+        removeModuleTSLoaderError(module, loaderOptions);
 
         // append errors
         const formattedErrors = formatErrors(
@@ -445,14 +447,18 @@ function provideAssetsFromSolutionBuilderHost(
  * the loader, we need to detect and remove any pre-existing errors.
  */
 function removeCompilationTSLoaderErrors(
-  compilation: webpack.compilation.Compilation
+  compilation: webpack.compilation.Compilation,
+  loaderOptions: LoaderOptions
 ) {
   compilation.errors = compilation.errors.filter(
-    error => error.loaderSource !== 'ts-loader'
+    error => error.loaderSource !== tsLoaderSource(loaderOptions)
   );
 }
 
-function removeModuleTSLoaderError(module: WebpackModule) {
+function removeModuleTSLoaderError(
+  module: WebpackModule,
+  loaderOptions: LoaderOptions
+) {
   /**
    * Since webpack 5, the `errors` property is deprecated,
    * so we can check if some methods for reporting errors exist.
@@ -464,11 +470,13 @@ function removeModuleTSLoaderError(module: WebpackModule) {
 
     Array.from(warnings || []).forEach(warning => module.addWarning(warning));
     Array.from(errors || [])
-      .filter((error: any) => error.loaderSource !== 'ts-loader')
+      .filter(
+        (error: any) => error.loaderSource !== tsLoaderSource(loaderOptions)
+      )
       .forEach(error => module.addError(error));
   } else {
     module.errors = module.errors.filter(
-      error => error.loaderSource !== 'ts-loader'
+      error => error.loaderSource !== tsLoaderSource(loaderOptions)
     );
   }
 }

src/instances.ts

@@ -13,7 +13,6 @@ import {
   LoaderOptions,
   TSFiles,
   TSInstance,
-  TSInstances,
   WebpackError,
 } from './interfaces';
 import * as logger from './logger';
@@ -34,7 +33,8 @@ import {
 } from './utils';
 import { makeWatchRun } from './watch-run';
 
-const instances = {} as TSInstances;
+const instances = new Map<string, TSInstance>();
+const instancesBySolutionBuilderConfigs = new Map<FilePathKey, TSInstance>();
 
 /**
  * The loader is executed once for each file seen by webpack. However, we need to keep
@@ -47,20 +47,26 @@ export function getTypeScriptInstance(
   loaderOptions: LoaderOptions,
   loader: webpack.loader.LoaderContext
 ): { instance?: TSInstance; error?: WebpackError } {
-  if (instances.hasOwnProperty(loaderOptions.instance)) {
-    const instance = instances[loaderOptions.instance];
-    if (!instance.initialSetupPending) {
-      ensureProgram(instance);
+  const existing = instances.get(loaderOptions.instance);
+  if (existing) {
+    if (!existing.initialSetupPending) {
+      ensureProgram(existing);
     }
-    return { instance: instances[loaderOptions.instance] };
+    return { instance: existing };
   }
 
   const colors = new chalk.constructor({ enabled: loaderOptions.colors });
   const log = logger.makeLogger(loaderOptions, colors);
   const compiler = getCompiler(loaderOptions, log);
 
   if (compiler.errorMessage !== undefined) {
-    return { error: makeError(colors.red(compiler.errorMessage), undefined) };
+    return {
+      error: makeError(
+        loaderOptions,
+        colors.red(compiler.errorMessage),
+        undefined
+      ),
+    };
   }
 
   return successfulTypeScriptInstance(
@@ -121,13 +127,25 @@ function successfulTypeScriptInstance(
     const { message, file } = configFileAndPath.configFileError;
     return {
       error: makeError(
+        loaderOptions,
         colors.red('error while reading tsconfig.json:' + EOL + message),
         file
       ),
     };
   }
 
   const { configFilePath, configFile } = configFileAndPath;
+  const filePathKeyMapper = createFilePathKeyMapper(compiler, loaderOptions);
+  if (configFilePath && loaderOptions.projectReferences) {
+    const configFileKey = filePathKeyMapper(configFilePath);
+    const existing = getExistingSolutionBuilderHost(configFileKey);
+    if (existing) {
+      // Reuse the instance if config file for project references is shared.
+      instances.set(loaderOptions.instance, existing);
+      return { instance: existing };
+    }
+  }
+
   const basePath = loaderOptions.context || path.dirname(configFilePath || '');
   const configParseResult = getConfigParseResult(
     compiler,
@@ -151,6 +169,7 @@ function successfulTypeScriptInstance(
 
     return {
       error: makeError(
+        loaderOptions,
         colors.red('error while parsing tsconfig.json'),
         configFilePath
       ),
@@ -174,12 +193,11 @@ function successfulTypeScriptInstance(
             filePath
           )
       : (filePath: string) => filePath;
-  const filePathKeyMapper = createFilePathKeyMapper(compiler, loaderOptions);
 
   if (loaderOptions.transpileOnly) {
     // quick return for transpiling
     // we do need to check for any issues with TS options though
-    const transpileInstance: TSInstance = (instances[loaderOptions.instance] = {
+    const transpileInstance: TSInstance = {
       compiler,
       compilerOptions,
       appendTsTsxSuffixesIfRequired,
@@ -198,8 +216,8 @@ function successfulTypeScriptInstance(
       configParseResult,
       log,
       filePathKeyMapper,
-    });
-
+    };
+    instances.set(loaderOptions.instance, transpileInstance);
     return { instance: transpileInstance };
   }
 
@@ -223,6 +241,7 @@ function successfulTypeScriptInstance(
   } catch (exc) {
     return {
       error: makeError(
+        loaderOptions,
         colors.red(
           `A file specified in tsconfig.json could not be found: ${normalizedFilePath!}`
         ),
@@ -231,7 +250,7 @@ function successfulTypeScriptInstance(
     };
   }
 
-  const instance: TSInstance = (instances[loaderOptions.instance] = {
+  const instance: TSInstance = {
     compiler,
     compilerOptions,
     appendTsTsxSuffixesIfRequired,
@@ -249,11 +268,22 @@ function successfulTypeScriptInstance(
     configParseResult,
     log,
     filePathKeyMapper,
-  });
-
+  };
+  instances.set(loaderOptions.instance, instance);
   return { instance };
 }
 
+function getExistingSolutionBuilderHost(key: FilePathKey) {
+  const existing = instancesBySolutionBuilderConfigs.get(key);
+  if (existing) return existing;
+  for (const instance of instancesBySolutionBuilderConfigs.values()) {
+    if (instance.solutionBuilderHost!.configFileInfo.has(key)) {
+      return instance;
+    }
+  }
+  return undefined;
+}
+
 export function initializeInstance(
   loader: webpack.loader.LoaderContext,
   instance: TSInstance
@@ -421,13 +451,17 @@ export function buildSolutionReferences(
       loader,
       instance
     );
-    instance.solutionBuilder = instance.compiler.createSolutionBuilderWithWatch(
+    const solutionBuilder = instance.compiler.createSolutionBuilderWithWatch(
       instance.solutionBuilderHost,
       instance.configParseResult.projectReferences!.map(ref => ref.path),
       { verbose: true }
     );
-    instance.solutionBuilder!.build();
+    solutionBuilder.build();
     ensureAllReferences(instance);
+    instancesBySolutionBuilderConfigs.set(
+      instance.filePathKeyMapper(instance.configFilePath!),
+      instance
+    );
   } else {
     instance.solutionBuilderHost.buildReferences();
   }

src/interfaces.ts

@@ -204,9 +204,6 @@ export interface TSInstance {
 
   reportTranspileErrors?: boolean;
   solutionBuilderHost?: SolutionBuilderWithWatchHost;
-  solutionBuilder?: typescript.SolutionBuilder<
-    typescript.EmitAndSemanticDiagnosticsBuilderProgram
-  >;
   configFilePath: string | undefined;
 
   filePathKeyMapper: (fileName: string) => FilePathKey;
@@ -220,9 +217,6 @@ export interface LoaderOptionsCache {
   [name: string]: WeakMap<LoaderOptions, LoaderOptions>;
 }
 
-export interface TSInstances {
-  [name: string]: TSInstance;
-}
 export type DependencyGraph = Map<FilePathKey, ResolvedModule[]>;
 export type ReverseDependencyGraph = Map<FilePathKey, Map<FilePathKey, true>>;
 

src/utils.ts

@@ -100,6 +100,7 @@ export function formatErrors(
               : loaderOptions.errorFormatter(errorInfo, colors);
 
           const error = makeError(
+            loaderOptions,
             message,
             merge.file === undefined ? errorInfo.file : merge.file,
             position === undefined
@@ -124,6 +125,7 @@ export function fsReadFile(
 }
 
 export function makeError(
+  loaderOptions: LoaderOptions,
   message: string,
   file: string | undefined,
   location?: { line: number; character: number }
@@ -132,10 +134,14 @@ export function makeError(
     message,
     location,
     file,
-    loaderSource: 'ts-loader',
+    loaderSource: tsLoaderSource(loaderOptions),
   };
 }
 
+export function tsLoaderSource(loaderOptions: LoaderOptions) {
+  return `ts-loader-${loaderOptions.instance}`;
+}
+
 export function appendSuffixIfMatch(
   patterns: (RegExp | string)[],
   filePath: string,

test/comparison-tests/projectReferencesMultipleDifferentInstance/app/app.ts

@@ -0,0 +1,5 @@
+import { lib } from '../lib';
+import { utils } from "../utils";
+
+console.log(lib.one, lib.two, lib.three);
+utils();

test/comparison-tests/projectReferencesMultipleDifferentInstance/app/tsconfig.json

@@ -0,0 +1,12 @@
+{
+    "compilerOptions": {
+        "types": []
+    },
+    "files": [
+        "./app.ts"
+    ],
+    "references": [
+        { "path": "../lib" },
+        { "path": "../utils" },
+    ]
+}

test/comparison-tests/projectReferencesMultipleDifferentInstance/app/webpack.config.js

@@ -0,0 +1,22 @@
+var path = require('path')
+
+module.exports = {
+    mode: 'development',
+    entry: './app.ts',
+    output: {
+        filename: 'bundle.js'
+    },
+    resolve: {
+        extensions: ['.ts', '.js']
+    },
+    module: {
+        rules: [
+            { test: /(app|lib|common|indirect).+\.ts$/, loader: 'ts-loader', options: { projectReferences: true } },
+            { test: /utils.+\.ts$/, loader: 'ts-loader', options: { instance: 'different', projectReferences: true } }
+        ]
+    }
+}
+
+// for test harness purposes only, you would not need this in a normal project
+module.exports.resolveLoader = { alias: { 'ts-loader': require('path').join(__dirname, "../../../../index.js") } }
+

test/comparison-tests/projectReferencesMultipleDifferentInstance/common/index.ts

@@ -0,0 +1,3 @@
+export function common() {
+  return 30;
+}

test/comparison-tests/projectReferencesMultipleDifferentInstance/common/tsconfig.json

@@ -0,0 +1,6 @@
+{
+  "compilerOptions": {
+    "composite": true,
+    "types": []
+  }
+}