start introducing strict-boolean-expressions (TypeStrong#855)

* start introducing strict-boolean-expressions

* more micro optimisation

* prepare to release

Author: johnnyreilly

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 5.2.2
+
+* [feat: Micro-optimizations](https://github.com/TypeStrong/ts-loader/pull/855) - thanks @johnnyreilly
+
 ## 5.2.1
 
 * [feat: Lists typescript as a peer dependency](https://github.com/TypeStrong/ts-loader/pull/841) - thanks @arcanis!

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ts-loader",
-  "version": "5.2.1",
+  "version": "5.2.2",
   "description": "TypeScript loader for webpack",
   "main": "index.js",
   "types": "dist/types/index.d.ts",

src/after-compile.ts

@@ -84,9 +84,9 @@ function provideCompilerOptionDiagnosticErrorsToWebpack(
     const { languageService, loaderOptions, compiler, program } = instance;
 
     const errorsToAdd = formatErrors(
-      program
-        ? program.getOptionsDiagnostics()
-        : languageService!.getCompilerOptionsDiagnostics(),
+      program === undefined
+        ? languageService!.getCompilerOptionsDiagnostics()
+        : program.getOptionsDiagnostics(),
       loaderOptions,
       instance.colors,
       compiler,
@@ -177,34 +177,37 @@ function provideErrorsToWebpack(
     otherFiles
   } = instance;
 
-  const filePathRegex = !!compilerOptions.checkJs
-    ? constants.dtsTsTsxJsJsxRegex
-    : constants.dtsTsTsxRegex;
+  const filePathRegex =
+    compilerOptions.checkJs === true
+      ? constants.dtsTsTsxJsJsxRegex
+      : constants.dtsTsTsxRegex;
 
   for (const filePath of filesToCheckForErrors.keys()) {
-    if (!filePath.match(filePathRegex)) {
+    if (filePath.match(filePathRegex) === null) {
       continue;
     }
 
-    const sourceFile = program && program.getSourceFile(filePath);
+    const sourceFile =
+      program === undefined ? undefined : program.getSourceFile(filePath);
 
     // If the source file is undefined, that probably means it’s actually part of an unbuilt project reference,
     // which will have already produced a more useful error than the one we would get by proceeding here.
     // If it’s undefined and we’re not using project references at all, I guess carry on so the user will
     // get a useful error about which file was unexpectedly missing.
-    if (isUsingProjectReferences(instance) && !sourceFile) {
+    if (isUsingProjectReferences(instance) && sourceFile === undefined) {
       continue;
     }
 
-    const errors = program
-      ? [
-          ...program.getSyntacticDiagnostics(sourceFile),
-          ...program.getSemanticDiagnostics(sourceFile)
-        ]
-      : [
-          ...languageService!.getSyntacticDiagnostics(filePath),
-          ...languageService!.getSemanticDiagnostics(filePath)
-        ];
+    const errors =
+      program === undefined
+        ? [
+            ...languageService!.getSyntacticDiagnostics(filePath),
+            ...languageService!.getSemanticDiagnostics(filePath)
+          ]
+        : [
+            ...program.getSyntacticDiagnostics(sourceFile),
+            ...program.getSemanticDiagnostics(sourceFile)
+          ];
     if (errors.length > 0) {
       const fileWithError = files.get(filePath) || otherFiles.get(filePath);
       filesWithErrors.set(filePath, fileWithError!);
@@ -255,7 +258,7 @@ function provideDeclarationFilesToWebpack(
   compilation: WebpackCompilation
 ) {
   for (const filePath of filesToCheckForErrors.keys()) {
-    if (!filePath.match(constants.tsTsxRegex)) {
+    if (filePath.match(constants.tsTsxRegex) === null) {
       continue;
     }
 

src/compilerSetup.ts

@@ -28,7 +28,10 @@ export function getCompiler(loaderOptions: LoaderOptions, log: logger.Logger) {
     }`;
     compilerCompatible = false;
     if (loaderOptions.compiler === 'typescript') {
-      if (compiler!.version && semver.gte(compiler!.version, '2.4.1')) {
+      if (
+        compiler!.version !== undefined &&
+        semver.gte(compiler!.version, '2.4.1')
+      ) {
         // don't log yet in this case, if a tsconfig.json exists we want to combine the message
         compilerCompatible = true;
       } else {

src/config.ts

@@ -98,7 +98,7 @@ function findConfigFile(
   // If `configFile` is a relative path, resolve it.
   // We define a relative path as: starts with
   // one or two dots + a common directory delimiter
-  if (configFile.match(/^\.\.?(\/|\\)/)) {
+  if (configFile.match(/^\.\.?(\/|\\)/) !== null) {
     const resolvedPath = path.resolve(requestDirPath, configFile);
     return compiler.sys.fileExists(resolvedPath) ? resolvedPath : undefined;
 

src/index.ts

@@ -30,7 +30,7 @@ const loaderOptionsCache: LoaderOptionsCache = {};
  * The entry point for ts-loader
  */
 function loader(this: Webpack, contents: string) {
-  // tslint:disable-next-line:no-unused-expression
+  // tslint:disable-next-line:no-unused-expression strict-boolean-expressions
   this.cacheable && this.cacheable();
   const callback = this.async();
   const options = getLoaderOptions(this);
@@ -80,7 +80,7 @@ function successLoader(
       ),
       path.relative(loaderContext.rootContext, filePath)
     ];
-    if (referencedProject.commandLine.options.outFile) {
+    if (referencedProject.commandLine.options.outFile !== undefined) {
       throw new Error(
         `The referenced project at ${relativeProjectConfigPath} is using ` +
           `the outFile' option, which is not supported with ts-loader.`
@@ -184,7 +184,7 @@ function makeSourceMapAndFinish(
   );
 
   // _module.meta is not available inside happypack
-  if (!options.happyPackMode && loaderContext._module.buildMeta) {
+  if (!options.happyPackMode && loaderContext._module.buildMeta !== undefined) {
     // Make sure webpack is aware that even though the emitted JavaScript may be the same as
     // a previously cached version the TypeScript may be different and therefore should be
     // treated as new
@@ -278,7 +278,10 @@ ${validLoaderOptions.join(' / ')}
     }
   }
 
-  if (loaderOptions.context && !path.isAbsolute(loaderOptions.context)) {
+  if (
+    loaderOptions.context !== undefined &&
+    !path.isAbsolute(loaderOptions.context)
+  ) {
     throw new Error(
       `Option 'context' has to be an absolute path. Given '${
         loaderOptions.context
@@ -342,7 +345,7 @@ function updateFileInCache(
       instance.otherFiles.delete(filePath);
       instance.files.set(filePath, file);
     } else {
-      if (instance.watchHost) {
+      if (instance.watchHost !== undefined) {
         fileWatcherEventKind = instance.compiler.FileWatcherEventKind.Created;
       }
       file = { version: 0 };
@@ -351,20 +354,23 @@ function updateFileInCache(
     instance.changedFilesList = true;
   }
 
-  if (instance.watchHost && contents === undefined) {
+  if (instance.watchHost !== undefined && contents === undefined) {
     fileWatcherEventKind = instance.compiler.FileWatcherEventKind.Deleted;
   }
 
   if (file.text !== contents) {
     file.version++;
     file.text = contents;
     instance.version!++;
-    if (instance.watchHost && fileWatcherEventKind === undefined) {
+    if (
+      instance.watchHost !== undefined &&
+      fileWatcherEventKind === undefined
+    ) {
       fileWatcherEventKind = instance.compiler.FileWatcherEventKind.Changed;
     }
   }
 
-  if (instance.watchHost && fileWatcherEventKind !== undefined) {
+  if (instance.watchHost !== undefined && fileWatcherEventKind !== undefined) {
     instance.hasUnaccountedModifiedFiles = true;
     instance.watchHost.invokeFileWatcher(filePath, fileWatcherEventKind);
     instance.watchHost.invokeDirectoryWatcher(path.dirname(filePath), filePath);
@@ -418,7 +424,7 @@ function getEmit(
             : originalFileName;
         });
 
-  if (additionalDependencies) {
+  if (additionalDependencies.length > 0) {
     additionalDependencies.forEach(addDependency);
   }
 
@@ -434,12 +440,13 @@ function getEmit(
   const outputFile = outputFiles
     .filter(file => file.name.match(constants.jsJsx))
     .pop();
-  const outputText = outputFile ? outputFile.text : undefined;
+  const outputText = outputFile === undefined ? undefined : outputFile.text;
 
   const sourceMapFile = outputFiles
     .filter(file => file.name.match(constants.jsJsxMap))
     .pop();
-  const sourceMapText = sourceMapFile ? sourceMapFile.text : undefined;
+  const sourceMapText =
+    sourceMapFile === undefined ? undefined : sourceMapFile.text;
 
   return { outputText, sourceMapText };
 }

src/instances.ts

@@ -222,9 +222,10 @@ function successfulTypeScriptInstance(
   }
 
   // if allowJs is set then we should accept js(x) files
-  const scriptRegex = configParseResult.options.allowJs
-    ? /\.tsx?$|\.jsx?$/i
-    : /\.tsx?$/i;
+  const scriptRegex =
+    configParseResult.options.allowJs === true
+      ? /\.tsx?$|\.jsx?$/i
+      : /\.tsx?$/i;
 
   const instance: TSInstance = (instances[loaderOptions.instance] = {
     compiler,
@@ -297,7 +298,7 @@ function successfulTypeScriptInstance(
 
 export function getEmitOutput(instance: TSInstance, filePath: string) {
   const program = ensureProgram(instance);
-  if (program) {
+  if (program !== undefined) {
     const outputFiles: typescript.OutputFile[] = [];
     const writeFile = (
       fileName: string,
@@ -318,8 +319,9 @@ export function getEmitOutput(instance: TSInstance, filePath: string) {
     return outputFiles;
   } else {
     // Emit Javascript
-    return instance.languageService!.getProgram()!.getSourceFile(filePath)
-      ? instance.languageService!.getEmitOutput(filePath).outputFiles
-      : [];
+    return instance.languageService!.getProgram()!.getSourceFile(filePath) ===
+      undefined
+      ? []
+      : instance.languageService!.getEmitOutput(filePath).outputFiles;
   }
 }

src/servicesHost.ts

@@ -251,15 +251,16 @@ export function makeWatchHost(
     invokeDirectoryWatcher,
     updateRootFileNames: () => {
       instance.changedFilesList = false;
-      if (instance.watchOfFilesAndCompilerOptions) {
+      if (instance.watchOfFilesAndCompilerOptions !== undefined) {
         instance.watchOfFilesAndCompilerOptions.updateRootFileNames(
           getRootFileNames()
         );
       }
     },
-    createProgram: projectReferences
-      ? createBuilderProgramWithReferences
-      : compiler.createAbstractBuilder
+    createProgram:
+      projectReferences === undefined
+        ? compiler.createAbstractBuilder
+        : createBuilderProgramWithReferences
   };
   return watchHost;
 
@@ -303,7 +304,7 @@ export function makeWatchHost(
     fileName: string,
     eventKind?: typescript.FileWatcherEventKind
   ) {
-    if (callbacks) {
+    if (callbacks !== undefined) {
       // The array copy is made to ensure that even if one of the callback removes the callbacks,
       // we dont miss any callbacks following it
       const cbs = callbacks.slice();
@@ -352,16 +353,16 @@ export function makeWatchHost(
   ): typescript.FileWatcher {
     file = path.normalize(file);
     const existing = callbacks[file];
-    if (existing) {
-      existing.push(callback);
-    } else {
+    if (existing === undefined) {
       callbacks[file] = [callback];
+    } else {
+      existing.push(callback);
     }
     return {
       close: () => {
         // tslint:disable-next-line:no-shadowed-variable
         const existing = callbacks[file];
-        if (existing) {
+        if (existing !== undefined) {
           unorderedRemoveItem(existing, callback);
         }
       }
@@ -383,7 +384,7 @@ export function makeWatchHost(
   ) {
     return createWatcher(
       fileName,
-      recursive ? watchedDirectoriesRecursive : watchedDirectories,
+      recursive === true ? watchedDirectoriesRecursive : watchedDirectories,
       callback
     );
   }
@@ -489,7 +490,7 @@ function resolveModuleName(
           )
         : originalFileName;
 
-    if (resolvedFileName.match(scriptRegex)) {
+    if (resolvedFileName.match(scriptRegex) !== null) {
       resolutionResult = { resolvedFileName, originalFileName };
     }
     // tslint:disable-next-line:no-empty

src/utils.ts

@@ -48,13 +48,17 @@ export function formatErrors(
   merge: { file?: string; module?: WebpackModule },
   context: string
 ): WebpackError[] {
-  return diagnostics
-    ? diagnostics
+  return diagnostics === undefined
+    ? []
+    : diagnostics
         .filter(diagnostic => {
           if (loaderOptions.ignoreDiagnostics.indexOf(diagnostic.code) !== -1) {
             return false;
           }
-          if (loaderOptions.reportFiles.length > 0 && diagnostic.file) {
+          if (
+            loaderOptions.reportFiles.length > 0 &&
+            diagnostic.file !== undefined
+          ) {
             const relativeFileName = path.relative(
               context,
               diagnostic.file.fileName
@@ -104,8 +108,7 @@ export function formatErrors(
           );
 
           return Object.assign(error, merge) as WebpackError;
-        })
-    : [];
+        });
 }
 
 export function readFile(
@@ -140,7 +143,7 @@ export function appendSuffixIfMatch(
 ): string {
   if (patterns.length > 0) {
     for (const regexp of patterns) {
-      if (filePath.match(regexp)) {
+      if (filePath.match(regexp) !== null) {
         return filePath + suffix;
       }
     }
@@ -367,7 +370,7 @@ export function getAndCacheOutputJSFileName(
     projectReference
   );
 
-  if (file) {
+  if (file !== undefined) {
     file.projectReference = file.projectReference || {
       project: projectReference
     };

src/watch-run.ts

@@ -22,7 +22,7 @@ export function makeWatchRun(instance: TSInstance) {
     for (const [filePath, date] of times) {
       if (
         date > (lastTimes.get(filePath) || startTime) &&
-        filePath.match(constants.tsTsxJsJsxRegex)
+        filePath.match(constants.tsTsxJsJsxRegex) !== null
       ) {
         continue;
       }
@@ -36,8 +36,8 @@ export function makeWatchRun(instance: TSInstance) {
     // (skip @types/* and modules with typings)
     for (const filePath of instance.files.keys()) {
       if (
-        filePath.match(constants.dtsDtsxOrDtsDtsxMapRegex) &&
-        !filePath.match(constants.nodeModules)
+        filePath.match(constants.dtsDtsxOrDtsDtsxMapRegex) !== null &&
+        filePath.match(constants.nodeModules) === null
       ) {
         updateFile(instance, filePath);
       }
@@ -56,7 +56,7 @@ function updateFile(instance: TSInstance, filePath: string) {
     file.version++;
     instance.version!++;
     instance.modifiedFiles!.set(nFilePath, file);
-    if (instance.watchHost) {
+    if (instance.watchHost !== undefined) {
       instance.watchHost.invokeFileWatcher(
         nFilePath,
         instance.compiler.FileWatcherEventKind.Changed