perf(core): Reuse emptyDirPaths from initial searchFiles to eliminate redundant filesystem scan

src/core/output/outputGenerate.ts

@@ -4,7 +4,7 @@ import { XMLBuilder } from 'fast-xml-parser';
 import Handlebars from 'handlebars';
 import type { RepomixConfigMerged } from '../../config/configSchema.js';
 import { RepomixError } from '../../shared/errorHandle.js';
-import { type FileSearchResult, listDirectories, listFiles, searchFiles } from '../file/fileSearch.js';
+import { listDirectories, listFiles, searchFiles } from '../file/fileSearch.js';
 import { type FilesByRoot, generateTreeString, generateTreeStringWithRoots } from '../file/fileTreeGenerate.js';
 import type { ProcessedFile } from '../file/fileTypes.js';
 import type { GitDiffResult } from '../git/gitDiffHandle.js';
@@ -258,6 +258,7 @@ export const generateOutput = async (
   gitDiffResult: GitDiffResult | undefined = undefined,
   gitLogResult: GitLogResult | undefined = undefined,
   filePathsByRoot?: FilesByRoot[],
+  emptyDirPaths?: string[],
   deps = {
     buildOutputGeneratorContext,
     generateHandlebarOutput,
@@ -277,6 +278,7 @@ export const generateOutput = async (
     gitDiffResult,
     gitLogResult,
     filePathsByRoot,
+    emptyDirPaths,
   );
   const renderContext = createRenderContext(outputGeneratorContext);
 
@@ -303,6 +305,7 @@ export const buildOutputGeneratorContext = async (
   gitDiffResult: GitDiffResult | undefined = undefined,
   gitLogResult: GitLogResult | undefined = undefined,
   filePathsByRoot?: FilesByRoot[],
+  emptyDirPaths?: string[],
   deps = {
     listDirectories,
     listFiles,
@@ -356,21 +359,21 @@ export const buildOutputGeneratorContext = async (
     }
   } else if (config.output.directoryStructure && config.output.includeEmptyDirectories) {
     // Default behavior: include empty directories only
-    try {
-      const merged = (await Promise.all(rootDirs.map((rootDir) => deps.searchFiles(rootDir, config)))).reduce(
-        (acc: FileSearchResult, curr: FileSearchResult) =>
-          ({
-            filePaths: [...acc.filePaths, ...curr.filePaths],
-            emptyDirPaths: [...acc.emptyDirPaths, ...curr.emptyDirPaths],
-          }) as FileSearchResult,
-        { filePaths: [], emptyDirPaths: [] },
-      ).emptyDirPaths;
-      directoryPathsForTree = [...new Set(merged)].sort();
-    } catch (error) {
-      throw new RepomixError(
-        `Failed to search for empty directories: ${error instanceof Error ? error.message : String(error)}`,
-        error instanceof Error ? { cause: error } : undefined,
-      );
+    if (emptyDirPaths) {
+      // Use pre-computed empty directory paths from the initial searchFiles call
+      directoryPathsForTree = emptyDirPaths;
+    } else {
+      // Fallback: if emptyDirPaths not provided (e.g., direct callers like packSkill)
+      try {
+        const searchResults = await Promise.all(rootDirs.map((rootDir) => deps.searchFiles(rootDir, config)));
+        const allEmptyDirs = searchResults.flatMap((result) => result.emptyDirPaths);
+        directoryPathsForTree = [...new Set(allEmptyDirs)].sort();
+      } catch (error) {
+        throw new RepomixError(
+          `Failed to search for empty directories: ${error instanceof Error ? error.message : String(error)}`,
+          error instanceof Error ? { cause: error } : undefined,
+        );
+      }
     }
   }
 

src/core/output/outputSplit.ts

@@ -101,6 +101,7 @@ const renderGroups = async (
   gitDiffResult: GitDiffResult | undefined,
   gitLogResult: GitLogResult | undefined,
   filePathsByRoot: FilesByRoot[] | undefined,
+  emptyDirPaths: string[] | undefined,
   generateOutput: GenerateOutputFn,
 ): Promise<string> => {
   const chunkProcessedFiles = groupsToRender.flatMap((g) => g.processedFiles);
@@ -115,6 +116,7 @@ const renderGroups = async (
     partIndex === 1 ? gitDiffResult : undefined,
     partIndex === 1 ? gitLogResult : undefined,
     filePathsByRoot,
+    emptyDirPaths,
   );
 };
 
@@ -128,6 +130,7 @@ export const generateSplitOutputParts = async ({
   gitLogResult,
   progressCallback,
   filePathsByRoot,
+  emptyDirPaths,
   deps,
 }: {
   rootDirs: string[];
@@ -139,6 +142,7 @@ export const generateSplitOutputParts = async ({
   gitLogResult: GitLogResult | undefined;
   progressCallback: RepomixProgressCallback;
   filePathsByRoot?: FilesByRoot[];
+  emptyDirPaths?: string[];
   deps: {
     generateOutput: GenerateOutputFn;
   };
@@ -178,6 +182,7 @@ export const generateSplitOutputParts = async ({
       gitDiffResult,
       gitLogResult,
       filePathsByRoot,
+      emptyDirPaths,
       deps.generateOutput,
     );
     const nextBytes = getUtf8ByteLength(nextContent);
@@ -215,6 +220,7 @@ export const generateSplitOutputParts = async ({
       gitDiffResult,
       gitLogResult,
       filePathsByRoot,
+      emptyDirPaths,
       deps.generateOutput,
     );
     const singleGroupBytes = getUtf8ByteLength(singleGroupContent);

src/core/packager.ts

@@ -69,15 +69,18 @@ export const pack = async (
   logMemoryUsage('Pack - Start');
 
   progressCallback('Searching for files...');
-  const filePathsByDir = await withMemoryLogging('Search Files', async () =>
+  const searchResultsByDir = await withMemoryLogging('Search Files', async () =>
     Promise.all(
-      rootDirs.map(async (rootDir) => ({
-        rootDir,
-        filePaths: (await deps.searchFiles(rootDir, config, explicitFiles)).filePaths,
-      })),
+      rootDirs.map(async (rootDir) => {
+        const result = await deps.searchFiles(rootDir, config, explicitFiles);
+        return { rootDir, ...result };
+      }),
     ),
   );
 
+  const filePathsByDir = searchResultsByDir.map(({ rootDir, filePaths }) => ({ rootDir, filePaths }));
+  const allEmptyDirPaths = [...new Set(searchResultsByDir.flatMap(({ emptyDirPaths }) => emptyDirPaths))].sort();
+
   // Sort file paths
   progressCallback('Sorting files...');
   const allFilePaths = filePathsByDir.flatMap(({ filePaths }) => filePaths);
@@ -167,6 +170,7 @@ export const pack = async (
     gitLogResult,
     progressCallback,
     filePathsByRoot,
+    allEmptyDirPaths,
   );
 
   const metrics = await withMemoryLogging('Calculate Metrics', () =>

src/core/packager/produceOutput.ts

@@ -30,6 +30,7 @@ export const produceOutput = async (
   gitLogResult: GitLogResult | undefined,
   progressCallback: RepomixProgressCallback,
   filePathsByRoot?: FilesByRoot[],
+  emptyDirPaths?: string[],
   overrideDeps: Partial<typeof defaultDeps> = {},
 ): Promise<ProduceOutputResult> => {
   const deps = { ...defaultDeps, ...overrideDeps };
@@ -47,6 +48,7 @@ export const produceOutput = async (
       gitLogResult,
       progressCallback,
       filePathsByRoot,
+      emptyDirPaths,
       deps,
     );
   }
@@ -60,6 +62,7 @@ export const produceOutput = async (
     gitLogResult,
     progressCallback,
     filePathsByRoot,
+    emptyDirPaths,
     deps,
   );
 };
@@ -74,6 +77,7 @@ const generateAndWriteSplitOutput = async (
   gitLogResult: GitLogResult | undefined,
   progressCallback: RepomixProgressCallback,
   filePathsByRoot: FilesByRoot[] | undefined,
+  emptyDirPaths: string[] | undefined,
   deps: typeof defaultDeps,
 ): Promise<ProduceOutputResult> => {
   const parts = await withMemoryLogging('Generate Split Output', async () => {
@@ -87,6 +91,7 @@ const generateAndWriteSplitOutput = async (
       gitLogResult,
       progressCallback,
       filePathsByRoot,
+      emptyDirPaths,
       deps: {
         generateOutput: deps.generateOutput,
       },
@@ -124,10 +129,20 @@ const generateAndWriteSingleOutput = async (
   gitLogResult: GitLogResult | undefined,
   progressCallback: RepomixProgressCallback,
   filePathsByRoot: FilesByRoot[] | undefined,
+  emptyDirPaths: string[] | undefined,
   deps: typeof defaultDeps,
 ): Promise<ProduceOutputResult> => {
   const output = await withMemoryLogging('Generate Output', () =>
-    deps.generateOutput(rootDirs, config, processedFiles, allFilePaths, gitDiffResult, gitLogResult, filePathsByRoot),
+    deps.generateOutput(
+      rootDirs,
+      config,
+      processedFiles,
+      allFilePaths,
+      gitDiffResult,
+      gitLogResult,
+      filePathsByRoot,
+      emptyDirPaths,
+    ),
   );
 
   progressCallback('Writing output file...');

tests/core/output/diffsInOutput.test.ts

@@ -131,6 +131,7 @@ index 123..456 100644
       gitDiffResult,
       undefined,
       undefined,
+      undefined,
       {
         buildOutputGeneratorContext: mockBuildOutputGeneratorContext,
         generateHandlebarOutput: mockGenerateHandlebarOutput,
@@ -204,6 +205,7 @@ index 123..456 100644
       gitDiffResult,
       undefined,
       undefined,
+      undefined,
       {
         buildOutputGeneratorContext: mockBuildOutputGeneratorContext,
         generateHandlebarOutput: mockGenerateHandlebarOutput,

tests/core/output/flagFullDirectoryStructure.test.ts

@@ -72,6 +72,7 @@ describe('includeFullDirectoryStructure flag', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       deps,
     );
 
@@ -105,6 +106,7 @@ describe('includeFullDirectoryStructure flag', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       deps,
     );
 

tests/core/output/outputGenerate.test.ts

@@ -49,6 +49,7 @@ describe('outputGenerate', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 
@@ -61,6 +62,7 @@ describe('outputGenerate', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
     );
     expect(output).toBe('mock output');
   });

tests/core/output/outputGenerateDiffs.test.ts

@@ -88,6 +88,7 @@ describe('Output Generation with Diffs', () => {
       gitDiffResult,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 
@@ -123,6 +124,7 @@ describe('Output Generation with Diffs', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 
@@ -158,6 +160,7 @@ describe('Output Generation with Diffs', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 
@@ -193,6 +196,7 @@ describe('Output Generation with Diffs', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 
@@ -238,6 +242,7 @@ describe('Output Generation with Diffs', () => {
       undefined,
       undefined,
       undefined,
+      undefined,
       mockDeps,
     );
 

tests/core/packager.test.ts

@@ -99,6 +99,7 @@ describe('packager', () => {
       undefined,
       progressCallback,
       [{ rootLabel: 'root', files: mockFilePaths }],
+      [],
     );
     expect(mockDeps.calculateMetrics).toHaveBeenCalledWith(
       mockProcessedFiles,

tests/core/packager/produceOutput.test.ts

@@ -26,6 +26,7 @@ describe('produceOutput', () => {
         undefined,
         progressCallback,
         undefined,
+        undefined,
         mockDeps,
       );
 
@@ -37,6 +38,7 @@ describe('produceOutput', () => {
         undefined,
         undefined,
         undefined,
+        undefined,
       );
       expect(mockDeps.writeOutputToDisk).toHaveBeenCalledWith('generated output', mockConfig);
       expect(mockDeps.copyToClipboardIfEnabled).toHaveBeenCalledWith('generated output', progressCallback, mockConfig);
@@ -61,6 +63,7 @@ describe('produceOutput', () => {
         gitLogResult as Parameters<typeof produceOutput>[5],
         vi.fn(),
         undefined,
+        undefined,
         mockDeps,
       );
 
@@ -72,6 +75,7 @@ describe('produceOutput', () => {
         gitDiffResult,
         gitLogResult,
         undefined,
+        undefined,
       );
     });
 
@@ -80,7 +84,18 @@ describe('produceOutput', () => {
       const mockConfig = createMockConfig();
       const progressCallback = vi.fn();
 
-      await produceOutput(['/root'], mockConfig, [], [], undefined, undefined, progressCallback, undefined, mockDeps);
+      await produceOutput(
+        ['/root'],
+        mockConfig,
+        [],
+        [],
+        undefined,
+        undefined,
+        progressCallback,
+        undefined,
+        undefined,
+        mockDeps,
+      );
 
       expect(progressCallback).toHaveBeenCalledWith('Writing output file...');
     });
@@ -116,6 +131,7 @@ describe('produceOutput', () => {
         undefined,
         progressCallback,
         undefined,
+        undefined,
         mockDeps,
       );
 
@@ -134,7 +150,18 @@ describe('produceOutput', () => {
       });
       const progressCallback = vi.fn();
 
-      await produceOutput(['/root'], mockConfig, [], [], undefined, undefined, progressCallback, undefined, mockDeps);
+      await produceOutput(
+        ['/root'],
+        mockConfig,
+        [],
+        [],
+        undefined,
+        undefined,
+        progressCallback,
+        undefined,
+        undefined,
+        mockDeps,
+      );
 
       expect(progressCallback).toHaveBeenCalledWith('Writing output files...');
     });
@@ -148,7 +175,7 @@ describe('produceOutput', () => {
         },
       });
 
-      await produceOutput(['/root'], mockConfig, [], [], undefined, undefined, vi.fn(), undefined, mockDeps);
+      await produceOutput(['/root'], mockConfig, [], [], undefined, undefined, vi.fn(), undefined, undefined, mockDeps);
 
       expect(mockDeps.copyToClipboardIfEnabled).not.toHaveBeenCalled();
     });