Copy js or dts bundle from old build if emitting only js or dts files

src/compiler/builder.ts

@@ -69,6 +69,7 @@ namespace ts {
          * Name of the file whose dts was the latest to change
          */
         latestChangedDtsFile: string | undefined;
+        bundle?: BundleBuildInfo;
     }
 
     export const enum BuilderFileEmit {
@@ -312,9 +313,10 @@ namespace ts {
                 }
             }
         }
-        // If this program has prepend references, always emit since we wont know if files on disk are correct unless we check file hash for correctness
-        if (outFilePath && !state.changedFilesSet.size && some(newProgram.getProjectReferences(), ref => !!ref.prepend)) {
-            state.programEmitPending = getBuilderFileEmit(compilerOptions);
+        if (outFilePath && !state.changedFilesSet.size) {
+            if (useOldState) state.bundle = oldState!.bundle;
+            // If this program has prepend references, always emit since we wont know if files on disk are correct unless we check file hash for correctness
+            if (some(newProgram.getProjectReferences(), ref => !!ref.prepend)) state.programEmitPending = getBuilderFileEmit(compilerOptions);
         }
         return state;
     }
@@ -914,7 +916,7 @@ namespace ts {
     /**
      * Gets the program information to be emitted in buildInfo so that we can use it to create new program
      */
-    function getProgramBuildInfo(state: BuilderProgramState, getCanonicalFileName: GetCanonicalFileName): ProgramBuildInfo | undefined {
+    function getBuildInfo(state: BuilderProgramState, getCanonicalFileName: GetCanonicalFileName, bundle: BundleBuildInfo | undefined): BuildInfo {
         const currentDirectory = Debug.checkDefined(state.program).getCurrentDirectory();
         const buildInfoDirectory = getDirectoryPath(getNormalizedAbsolutePath(getTsBuildInfoEmitOutputFilePath(state.compilerOptions)!, currentDirectory));
         // Convert the file name to Path here if we set the fileName instead to optimize multiple d.ts file emits and having to compute Canonical path
@@ -929,7 +931,7 @@ namespace ts {
                     { version: value.version, impliedFormat: value.impliedFormat, signature: undefined, affectsGlobalScope: undefined } :
                     value.version;
             });
-            const result: ProgramBundleEmitBuildInfo = {
+            const program: ProgramBundleEmitBuildInfo = {
                 fileNames,
                 fileInfos,
                 options: convertToProgramBuildInfoCompilerOptions(state.compilerOptions),
@@ -942,7 +944,14 @@ namespace ts {
                         false :
                         state.programEmitPending,
             };
-            return result;
+            const { js, dts, commonSourceDirectory, sourceFiles } = bundle!;
+            state.bundle = bundle = {
+                commonSourceDirectory,
+                sourceFiles,
+                js: js || (!state.compilerOptions.emitDeclarationOnly ? state.bundle?.js : undefined),
+                dts: dts || (getEmitDeclarations(state.compilerOptions) ? state.bundle?.dts : undefined),
+            };
+            return createBuildInfo(program, bundle);
         }
 
         let fileIdsList: (readonly ProgramBuildInfoFileId[])[] | undefined;
@@ -1042,7 +1051,7 @@ namespace ts {
             }
         }
 
-        const result: ProgramMultiFileEmitBuildInfo = {
+        const program: ProgramMultiFileEmitBuildInfo = {
             fileNames,
             fileInfos,
             options: convertToProgramBuildInfoCompilerOptions(state.compilerOptions),
@@ -1056,7 +1065,7 @@ namespace ts {
             emitSignatureDtsMapDiffers,
             latestChangedDtsFile,
         };
-        return result;
+        return createBuildInfo(program, bundle);
 
         function relativeToBuildInfoEnsuringAbsolutePath(path: string) {
             return relativeToBuildInfo(getNormalizedAbsolutePath(path, currentDirectory));
@@ -1252,7 +1261,7 @@ namespace ts {
          */
         const computeHash = maybeBind(host, host.createHash);
         const state = createBuilderProgramState(newProgram, getCanonicalFileName, oldState, host.disableUseFileVersionAsSignature);
-        newProgram.getProgramBuildInfo = () => getProgramBuildInfo(state, getCanonicalFileName);
+        newProgram.getBuildInfo = bundle => getBuildInfo(state, getCanonicalFileName, bundle);
 
         // To ensure that we arent storing any references to old program or new program without state
         newProgram = undefined!; // TODO: GH#18217
@@ -1587,7 +1596,8 @@ namespace ts {
         return !value ? getBuilderFileEmit(options || {}) : value;
     }
 
-    export function createBuilderProgramUsingProgramBuildInfo(program: ProgramBuildInfo, buildInfoPath: string, host: ReadBuildProgramHost): EmitAndSemanticDiagnosticsBuilderProgram {
+    export function createBuilderProgramUsingProgramBuildInfo(buildInfo: BuildInfo, buildInfoPath: string, host: ReadBuildProgramHost): EmitAndSemanticDiagnosticsBuilderProgram {
+        const program = buildInfo.program!;
         const buildInfoDirectory = getDirectoryPath(getNormalizedAbsolutePath(buildInfoPath, host.getCurrentDirectory()));
         const getCanonicalFileName = createGetCanonicalFileName(host.useCaseSensitiveFileNames());
 
@@ -1608,6 +1618,7 @@ namespace ts {
                 outSignature: program.outSignature,
                 outSignatureDtsMapDiffers: program.outSignatureDtsMapDiffers,
                 programEmitPending: program.pendingEmit === undefined ? undefined : toProgramEmitPending(program.pendingEmit, program.options),
+                bundle: buildInfo.bundle,
             };
         }
         else {

src/compiler/emitter.ts

@@ -358,13 +358,11 @@ namespace ts {
         function emitBuildInfo(bundle: BundleBuildInfo | undefined, buildInfoPath: string | undefined) {
             // Write build information if applicable
             if (!buildInfoPath || targetSourceFile || emitSkipped) return;
-            const program = host.getProgramBuildInfo();
             if (host.isEmitBlocked(buildInfoPath)) {
                 emitSkipped = true;
                 return;
             }
-            const version = ts.version; // Extracted into a const so the form is stable between namespace and module
-            const buildInfo: BuildInfo = { bundle, program, version };
+            const buildInfo = host.getBuildInfo(bundle) || createBuildInfo(/*program*/ undefined, bundle);
             // Pass buildinfo as additional data to avoid having to reparse
             writeFile(host, emitterDiagnostics, buildInfoPath, getBuildInfoText(buildInfo), /*writeByteOrderMark*/ false, /*sourceFiles*/ undefined, { buildInfo });
         }
@@ -646,6 +644,12 @@ namespace ts {
         }
     }
 
+    /*@internal*/
+    export function createBuildInfo(program: ProgramBuildInfo | undefined, bundle: BundleBuildInfo | undefined): BuildInfo {
+        const version = ts.version; // Extracted into a const so the form is stable between namespace and module
+        return { bundle, program, version };
+    }
+
     /*@internal*/
     export function getBuildInfoText(buildInfo: BuildInfo) {
         return JSON.stringify(buildInfo);
@@ -825,21 +829,7 @@ namespace ts {
                         if (sourceMapText === text) return;
                         break;
                     case buildInfoPath:
-                        const newBuildInfo = data!.buildInfo!;
-                        newBuildInfo.program = buildInfo!.program;
-                        if (newBuildInfo.program && changedDtsText !== undefined && config.options.composite) {
-                            // Update the output signature
-                            (newBuildInfo.program as ProgramBundleEmitBuildInfo).outSignature = computeSignature(changedDtsText, createHash, changedDtsData);
-                        }
-                        // Update sourceFileInfo
-                        const { js, dts, sourceFiles } = buildInfo!.bundle!;
-                        newBuildInfo.bundle!.js!.sources = js!.sources;
-                        if (dts) {
-                            newBuildInfo.bundle!.dts!.sources = dts.sources;
-                        }
-                        newBuildInfo.bundle!.sourceFiles = sourceFiles;
-                        outputFiles.push({ name, text: getBuildInfoText(newBuildInfo), writeByteOrderMark, data: { buildInfo: newBuildInfo } });
-                        return;
+                        break;
                     case declarationFilePath:
                         if (declarationText === text) return;
                         changedDtsText = text;
@@ -851,13 +841,27 @@ namespace ts {
                     default:
                         Debug.fail(`Unexpected path: ${name}`);
                 }
-                outputFiles.push({ name, text, writeByteOrderMark });
+                outputFiles.push({ name, text, writeByteOrderMark, data });
             },
             isEmitBlocked: returnFalse,
             readFile: f => host.readFile(f),
             fileExists: f => host.fileExists(f),
             useCaseSensitiveFileNames: () => host.useCaseSensitiveFileNames(),
-            getProgramBuildInfo: returnUndefined,
+            getBuildInfo: bundle => {
+                const program = buildInfo!.program;
+                if (program && changedDtsText !== undefined && config.options.composite) {
+                    // Update the output signature
+                    (program as ProgramBundleEmitBuildInfo).outSignature = computeSignature(changedDtsText, createHash, changedDtsData);
+                }
+                // Update sourceFileInfo
+                const { js, dts, sourceFiles } = buildInfo!.bundle!;
+                bundle!.js!.sources = js!.sources;
+                if (dts) {
+                    bundle!.dts!.sources = dts.sources;
+                }
+                bundle!.sourceFiles = sourceFiles;
+                return createBuildInfo(program, bundle);
+            },
             getSourceFileFromReference: returnUndefined,
             redirectTargetsMap: createMultiMap(),
             getFileIncludeReasons: notImplemented,

src/compiler/program.ts

@@ -1948,7 +1948,7 @@ namespace ts {
                     return host.fileExists(f);
                 },
                 useCaseSensitiveFileNames: () => host.useCaseSensitiveFileNames(),
-                getProgramBuildInfo: () => program.getProgramBuildInfo && program.getProgramBuildInfo(),
+                getBuildInfo: bundle => program.getBuildInfo?.(bundle),
                 getSourceFileFromReference: (file, ref) => program.getSourceFileFromReference(file, ref),
                 redirectTargetsMap,
                 getFileIncludeReasons: program.getFileIncludeReasons,

src/compiler/types.ts

@@ -4469,7 +4469,7 @@ namespace ts {
         /*@internal*/ forEachResolvedProjectReference<T>(cb: (resolvedProjectReference: ResolvedProjectReference) => T | undefined): T | undefined;
         /*@internal*/ getResolvedProjectReferenceByPath(projectReferencePath: Path): ResolvedProjectReference | undefined;
         /*@internal*/ isSourceOfProjectReferenceRedirect(fileName: string): boolean;
-        /*@internal*/ getProgramBuildInfo?(): ProgramBuildInfo | undefined;
+        /*@internal*/ getBuildInfo?(bundle: BundleBuildInfo | undefined): BuildInfo;
         /*@internal*/ emitBuildInfo(writeFile?: WriteFileCallback, cancellationToken?: CancellationToken): EmitResult;
         /**
          * This implementation handles file exists to be true if file is source of project reference redirect when program is created using useSourceOfProjectReferenceRedirect
@@ -7533,7 +7533,7 @@ namespace ts {
         getPrependNodes(): readonly (InputFiles | UnparsedSource)[];
 
         writeFile: WriteFileCallback;
-        getProgramBuildInfo(): ProgramBuildInfo | undefined;
+        getBuildInfo(bundle: BundleBuildInfo | undefined): BuildInfo | undefined;
         getSourceFileFromReference: Program["getSourceFileFromReference"];
         readonly redirectTargetsMap: RedirectTargetsMap;
         createHash?(data: string): string;

src/compiler/watchPublic.ts

@@ -20,7 +20,7 @@ namespace ts {
             buildInfo = getBuildInfo(buildInfoPath, content);
         }
         if (!buildInfo || buildInfo.version !== version || !buildInfo.program) return undefined;
-        return createBuilderProgramUsingProgramBuildInfo(buildInfo.program, buildInfoPath, host);
+        return createBuilderProgramUsingProgramBuildInfo(buildInfo, buildInfoPath, host);
     }
 
     export function createIncrementalCompilerHost(options: CompilerOptions, system = sys): CompilerHost {