Merge pull request #25102 from Microsoft/declarationEmitWithNoEmitAndWatch

Mark the declarations visible correctly when emit is disabled but asked to emit declarations for watch mode

src/compiler/emitter.ts

@@ -192,6 +192,11 @@ namespace ts {
             // Setup and perform the transformation to retrieve declarations from the input files
             const nonJsFiles = filter(sourceFiles, isSourceFileNotJavaScript);
             const inputListOrBundle = (compilerOptions.outFile || compilerOptions.out) ? [createBundle(nonJsFiles, !isSourceFile(sourceFileOrBundle) ? sourceFileOrBundle.prepends : undefined)] : nonJsFiles;
+            if (emitOnlyDtsFiles && !compilerOptions.declaration) {
+                // Checker wont collect the linked aliases since thats only done when declaration is enabled.
+                // Do that here when emitting only dts files
+                nonJsFiles.forEach(collectLinkedAliases);
+            }
             const declarationTransform = transformNodes(resolver, host, compilerOptions, inputListOrBundle, concatenate([transformDeclarations], declarationTransformers), /*allowDtsFiles*/ false);
             if (length(declarationTransform.diagnostics)) {
                 for (const diagnostic of declarationTransform.diagnostics!) {
@@ -221,6 +226,20 @@ namespace ts {
             declarationTransform.dispose();
         }
 
+        function collectLinkedAliases(node: Node) {
+            if (isExportAssignment(node)) {
+                if (node.expression.kind === SyntaxKind.Identifier) {
+                    resolver.collectLinkedAliases(node.expression as Identifier, /*setVisibility*/ true);
+                }
+                return;
+            }
+            else if (isExportSpecifier(node)) {
+                resolver.collectLinkedAliases(node.propertyName || node.name, /*setVisibility*/ true);
+                return;
+            }
+            forEachChild(node, collectLinkedAliases);
+        }
+
         function printSourceFileOrBundle(jsFilePath: string, sourceMapFilePath: string | undefined, sourceFileOrBundle: SourceFile | Bundle, bundleInfoPath: string | undefined, printer: Printer, mapRecorder: SourceMapWriter) {
             const bundle = sourceFileOrBundle.kind === SyntaxKind.Bundle ? sourceFileOrBundle : undefined;
             const sourceFile = sourceFileOrBundle.kind === SyntaxKind.SourceFile ? sourceFileOrBundle : undefined;

src/compiler/types.ts

@@ -3331,7 +3331,7 @@ namespace ts {
         getNodeCheckFlags(node: Node): NodeCheckFlags;
         isDeclarationVisible(node: Declaration | AnyImportSyntax): boolean;
         isLateBound(node: Declaration): node is LateBoundDeclaration;
-        collectLinkedAliases(node: Identifier): Node[] | undefined;
+        collectLinkedAliases(node: Identifier, setVisibility?: boolean): Node[] | undefined;
         isImplementationOfOverload(node: FunctionLike): boolean | undefined;
         isRequiredInitializedParameter(node: ParameterDeclaration): boolean;
         isOptionalUninitializedParameterProperty(node: ParameterDeclaration): boolean;

src/harness/virtualFileSystemWithWatch.ts

@@ -571,7 +571,9 @@ interface Array<T> {}`
         }
 
         private addFileOrFolderInFolder(folder: FsFolder, fileOrDirectory: FsFile | FsFolder | FsSymLink, ignoreWatch?: boolean) {
-            insertSorted(folder.entries, fileOrDirectory, (a, b) => compareStringsCaseSensitive(getBaseFileName(a.path), getBaseFileName(b.path)));
+            if (!this.fs.has(fileOrDirectory.path)) {
+                insertSorted(folder.entries, fileOrDirectory, (a, b) => compareStringsCaseSensitive(getBaseFileName(a.path), getBaseFileName(b.path)));
+            }
             folder.modifiedTime = this.now();
             this.fs.set(fileOrDirectory.path, fileOrDirectory);
 

src/testRunner/unittests/tscWatchMode.ts

@@ -1218,6 +1218,58 @@ namespace ts.tscWatch {
                 checkWatchedFiles(host, files.map(f => f.path));
             }
         });
+
+        it("updates errors correctly when declaration emit is disabled in compiler options", () => {
+            const currentDirectory = "/user/username/projects/myproject";
+            const aFile: File = {
+                path: `${currentDirectory}/a.ts`,
+                content: `import test from './b';
+test(4, 5);`
+            };
+            const bFileContent = `function test(x: number, y: number) {
+    return x + y / 5;
+}
+export default test;`;
+            const bFile: File = {
+                path: `${currentDirectory}/b.ts`,
+                content: bFileContent
+            };
+            const tsconfigFile: File = {
+                path: `${currentDirectory}/tsconfig.json`,
+                content: JSON.stringify({
+                    compilerOptions: {
+                        module: "commonjs",
+                        noEmit: true,
+                        strict: true,
+                    }
+                })
+            };
+            const files = [aFile, bFile, libFile, tsconfigFile];
+            const host = createWatchedSystem(files, { currentDirectory });
+            const watch = createWatchOfConfigFile("tsconfig.json", host);
+            checkOutputErrorsInitial(host, emptyArray);
+
+            changeParameterType("x", "string", [
+                getDiagnosticOfFileFromProgram(watch(), aFile.path, aFile.content.indexOf("4"), 1, Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1, "4", "string")
+            ]);
+            changeParameterType("y", "string", [
+                getDiagnosticOfFileFromProgram(watch(), aFile.path, aFile.content.indexOf("5"), 1, Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1, "5", "string"),
+                getDiagnosticOfFileFromProgram(watch(), bFile.path, bFile.content.indexOf("y /"), 1, Diagnostics.The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type)
+            ]);
+
+            function changeParameterType(parameterName: string, toType: string, expectedErrors: ReadonlyArray<Diagnostic>) {
+                const newContent = bFileContent.replace(new RegExp(`${parameterName}\: [a-z]*`), `${parameterName}: ${toType}`);
+
+                verifyErrorsWithBFileContents(newContent, expectedErrors);
+                verifyErrorsWithBFileContents(bFileContent, emptyArray);
+            }
+
+            function verifyErrorsWithBFileContents(content: string, expectedErrors: ReadonlyArray<Diagnostic>) {
+                host.writeFile(bFile.path, content);
+                host.runQueuedTimeoutCallbacks();
+                checkOutputErrorsIncremental(host, expectedErrors);
+            }
+        });
     });
 
     describe("tsc-watch emit with outFile or out setting", () => {

tests/baselines/reference/api/tsserverlibrary.d.ts

@@ -2915,7 +2915,7 @@ declare namespace ts {
         getNodeCheckFlags(node: Node): NodeCheckFlags;
         isDeclarationVisible(node: Declaration | AnyImportSyntax): boolean;
         isLateBound(node: Declaration): node is LateBoundDeclaration;
-        collectLinkedAliases(node: Identifier): Node[] | undefined;
+        collectLinkedAliases(node: Identifier, setVisibility?: boolean): Node[] | undefined;
         isImplementationOfOverload(node: FunctionLike): boolean | undefined;
         isRequiredInitializedParameter(node: ParameterDeclaration): boolean;
         isOptionalUninitializedParameterProperty(node: ParameterDeclaration): boolean;