Mark file as skips typechecking if it contains ts-nocheck (#58593)

Author: sheetalkamat

src/compiler/checker.ts

@@ -62,6 +62,7 @@ import {
     canHaveModifiers,
     canHaveModuleSpecifier,
     canHaveSymbol,
+    canIncludeBindAndCheckDiagnsotics,
     canUsePropertyAccess,
     cartesianProduct,
     CaseBlock,
@@ -49066,7 +49067,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
     }
 
     function calculateNodeCheckFlagWorker(node: Node, flag: LazyNodeCheckFlags) {
-        if (!compilerOptions.noCheck) {
+        if (!compilerOptions.noCheck && canIncludeBindAndCheckDiagnsotics(getSourceFileOfNode(node), compilerOptions)) {
             // Unless noCheck is passed, assume calculation of node check flags has been done eagerly.
             // This saves needing to mark up where in the eager traversal certain results are "done",
             // just to reconcile the eager and lazy results. This wouldn't be hard if an eager typecheck

src/compiler/emitter.ts

@@ -21,6 +21,7 @@ import {
     CallExpression,
     CallSignatureDeclaration,
     canHaveLocals,
+    canIncludeBindAndCheckDiagnsotics,
     CaseBlock,
     CaseClause,
     CaseOrDefaultClause,
@@ -800,9 +801,14 @@ export function emitFiles(resolver: EmitResolver, host: EmitHost, targetSourceFi
             return;
         }
 
-        if (compilerOptions.noCheck) {
-            (isSourceFile(sourceFileOrBundle) ? [sourceFileOrBundle] : filter(sourceFileOrBundle.sourceFiles, isSourceFileNotJson)).forEach(markLinkedReferences);
-        }
+        (isSourceFile(sourceFileOrBundle) ? [sourceFileOrBundle] : filter(sourceFileOrBundle.sourceFiles, isSourceFileNotJson)).forEach(
+            sourceFile => {
+                if (
+                    compilerOptions.noCheck ||
+                    !canIncludeBindAndCheckDiagnsotics(sourceFile, compilerOptions)
+                ) markLinkedReferences(sourceFile);
+            },
+        );
 
         // Transform the source files
         const transform = transformNodes(resolver, host, factory, compilerOptions, [sourceFileOrBundle], scriptTransformers, /*allowDtsFiles*/ false);
@@ -859,15 +865,19 @@ export function emitFiles(resolver: EmitResolver, host: EmitHost, targetSourceFi
         const filesForEmit = forceDtsEmit ? sourceFiles : filter(sourceFiles, isSourceFileNotJson);
         // Setup and perform the transformation to retrieve declarations from the input files
         const inputListOrBundle = compilerOptions.outFile ? [factory.createBundle(filesForEmit)] : filesForEmit;
-        if (
-            (emitOnly && !getEmitDeclarations(compilerOptions)) ||
-            compilerOptions.noCheck ||
-            emitResolverSkipsTypeChecking(emitOnly, forceDtsEmit)
-        ) {
-            // Checker wont collect the linked aliases since thats only done when declaration is enabled and checking is performed.
-            // Do that here when emitting only dts files
-            filesForEmit.forEach(collectLinkedAliases);
-        }
+        // Checker wont collect the linked aliases since thats only done when declaration is enabled and checking is performed.
+        // Do that here when emitting only dts files
+        filesForEmit.forEach(sourceFile => {
+            if (
+                (emitOnly && !getEmitDeclarations(compilerOptions)) ||
+                compilerOptions.noCheck ||
+                emitResolverSkipsTypeChecking(emitOnly, forceDtsEmit) ||
+                !canIncludeBindAndCheckDiagnsotics(sourceFile, compilerOptions)
+            ) {
+                collectLinkedAliases(sourceFile);
+            }
+        });
+
         const declarationTransform = transformNodes(resolver, host, factory, compilerOptions, inputListOrBundle, declarationTransformers, /*allowDtsFiles*/ false);
         if (length(declarationTransform.diagnostics)) {
             for (const diagnostic of declarationTransform.diagnostics!) {

src/compiler/program.ts

@@ -3016,22 +3016,19 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
             const isJs = sourceFile.scriptKind === ScriptKind.JS || sourceFile.scriptKind === ScriptKind.JSX;
             const isCheckJs = isJs && isCheckJsEnabledForFile(sourceFile, options);
             const isPlainJs = isPlainJsFile(sourceFile, options.checkJs);
-            const isTsNoCheck = !!sourceFile.checkJsDirective && sourceFile.checkJsDirective.enabled === false;
 
             // By default, only type-check .ts, .tsx, Deferred, plain JS, checked JS and External
             // - plain JS: .js files with no // ts-check and checkJs: undefined
             // - check JS: .js files with either // ts-check or checkJs: true
             // - external: files that are added by plugins
-            const includeBindAndCheckDiagnostics = !isTsNoCheck && (sourceFile.scriptKind === ScriptKind.TS || sourceFile.scriptKind === ScriptKind.TSX
-                || sourceFile.scriptKind === ScriptKind.External || isPlainJs || isCheckJs || sourceFile.scriptKind === ScriptKind.Deferred);
-            let bindDiagnostics: readonly Diagnostic[] = includeBindAndCheckDiagnostics ? sourceFile.bindDiagnostics : emptyArray;
-            let checkDiagnostics = includeBindAndCheckDiagnostics ? typeChecker.getDiagnostics(sourceFile, cancellationToken) : emptyArray;
+            let bindDiagnostics = sourceFile.bindDiagnostics;
+            let checkDiagnostics = typeChecker.getDiagnostics(sourceFile, cancellationToken);
             if (isPlainJs) {
                 bindDiagnostics = filter(bindDiagnostics, d => plainJSErrors.has(d.code));
                 checkDiagnostics = filter(checkDiagnostics, d => plainJSErrors.has(d.code));
             }
             // skip ts-expect-error errors in plain JS files, and skip JSDoc errors except in checked JS
-            return getMergedBindAndCheckDiagnostics(sourceFile, includeBindAndCheckDiagnostics && !isPlainJs, bindDiagnostics, checkDiagnostics, isCheckJs ? sourceFile.jsDocDiagnostics : undefined);
+            return getMergedBindAndCheckDiagnostics(sourceFile, !isPlainJs, bindDiagnostics, checkDiagnostics, isCheckJs ? sourceFile.jsDocDiagnostics : undefined);
         });
     }
 

src/compiler/utilities.ts

@@ -10082,7 +10082,28 @@ export function skipTypeChecking(sourceFile: SourceFile, options: CompilerOption
     return (options.skipLibCheck && sourceFile.isDeclarationFile ||
         options.skipDefaultLibCheck && sourceFile.hasNoDefaultLib) ||
         options.noCheck ||
-        host.isSourceOfProjectReferenceRedirect(sourceFile.fileName);
+        host.isSourceOfProjectReferenceRedirect(sourceFile.fileName) ||
+        !canIncludeBindAndCheckDiagnsotics(sourceFile, options);
+}
+
+/** @internal */
+export function canIncludeBindAndCheckDiagnsotics(sourceFile: SourceFile, options: CompilerOptions) {
+    if (!!sourceFile.checkJsDirective && sourceFile.checkJsDirective.enabled === false) return false;
+    if (
+        sourceFile.scriptKind === ScriptKind.TS ||
+        sourceFile.scriptKind === ScriptKind.TSX ||
+        sourceFile.scriptKind === ScriptKind.External
+    ) return true;
+
+    const isJs = sourceFile.scriptKind === ScriptKind.JS || sourceFile.scriptKind === ScriptKind.JSX;
+    const isCheckJs = isJs && isCheckJsEnabledForFile(sourceFile, options);
+    const isPlainJs = isPlainJsFile(sourceFile, options.checkJs);
+
+    // By default, only type-check .ts, .tsx, Deferred, plain JS, checked JS and External
+    // - plain JS: .js files with no // ts-check and checkJs: undefined
+    // - check JS: .js files with either // ts-check or checkJs: true
+    // - external: files that are added by plugins
+    return isPlainJs || isCheckJs || sourceFile.scriptKind === ScriptKind.Deferred;
 }
 
 /** @internal */