Merge pull request #20 from romot-co/codex/refactor-fileoperations.scandirectory-for-streaming

Stream file reads during directory scan

Author: romot-co

src/__tests__/fileOperations.test.ts

@@ -1,12 +1,15 @@
 import * as fs from 'fs/promises';
+import * as fsStream from 'fs';
 import * as vscode from 'vscode';
-import { PathLike } from 'fs';
+import { PathLike, ReadStream } from 'fs';
+import { Readable } from 'stream';
 import * as path from 'path';
 import { FileOperations } from '../fileOperations';
 import { FileSizeLimitError, ScanError } from '../errors/errors';
 import { ScanOptions } from '../types/fileTypes';
 
 jest.mock('fs/promises');
+jest.mock('fs');
 jest.mock('../utils/fileUtils', () => ({
   isBinaryFile: (buf: Buffer | string) => String(buf).includes('BIN')
 }));
@@ -23,6 +26,7 @@ jest.mock('../utils/fileUtils', () => ({
 });
 
 const mockedFs = jest.mocked(fs);
+const mockedFsStream = jest.mocked(fsStream);
 const ROOT = '/ws';
 const BASE_OPTS: ScanOptions = {
   maxFileSize: 1024 * 1024,
@@ -47,6 +51,7 @@ beforeEach(() => {
   mockedFs.stat.mockReset();
   mockedFs.readdir.mockReset();
   mockedFs.readFile.mockReset();
+  mockedFsStream.createReadStream.mockReset();
   jest.clearAllMocks();
 });
 
@@ -68,8 +73,8 @@ describe('FileOperations: basics', () => {
       if (s === path.join(ROOT, 'src', 'b'))  return [d('c.js')];
       return [];
     });
-    // ③ readFile
-    mockedFs.readFile.mockResolvedValue('DATA');
+    // ③ createReadStream
+    mockedFsStream.createReadStream.mockImplementation(() => Readable.from(['DATA']) as unknown as ReadStream);
 
     const res = await fo.scanDirectory('src', BASE_OPTS);
 
@@ -93,7 +98,7 @@ describe('FileOperations: filters', () => {
   it('excludePatterns に一致するファイルを除外する', async () => {
     mockedFs.stat.mockImplementation((p) => smartStat(p));
     mockedFs.readdir.mockResolvedValue([d('skip.txt'), d('keep.txt')] as any[]);
-    mockedFs.readFile.mockResolvedValue('C');
+    mockedFsStream.createReadStream.mockImplementation(() => Readable.from(['C']) as unknown as ReadStream);
 
     const res = await fo.scanDirectory('.', {
       ...BASE_OPTS,
@@ -110,7 +115,7 @@ describe('FileOperations: filters', () => {
       return smartStat(p, tooLarge ? 2_000_000 : 100);
     });
     mockedFs.readdir.mockResolvedValue([d('small.txt'), d('large.txt')] as any[]);
-    mockedFs.readFile.mockResolvedValue('C');
+    mockedFsStream.createReadStream.mockImplementation(() => Readable.from(['C']) as unknown as ReadStream);
 
     const res = await fo.scanDirectory('.', BASE_OPTS);
     expect(res.files.map(f => f.relativePath)).toEqual(['small.txt']);
@@ -119,9 +124,11 @@ describe('FileOperations: filters', () => {
   it('バイナリファイルは除外される', async () => {
     mockedFs.stat.mockImplementation((p) => smartStat(p));
     mockedFs.readdir.mockResolvedValue([d('text.txt'), d('binary.dat')] as any[]);
-    mockedFs.readFile.mockImplementation((async (p: PathLike) =>
-      path.basename(String(p)).startsWith('binary') ? Buffer.from('BIN') : Buffer.from('TXT')
-    ) as any);
+    mockedFsStream.createReadStream.mockImplementation((p: PathLike) => {
+      const base = path.basename(String(p));
+      const data = base.startsWith('binary') ? 'BIN' : 'TXT';
+      return Readable.from([data]) as unknown as ReadStream;
+    });
 
     const res = await fo.scanDirectory('.', BASE_OPTS);
     expect(res.files.map(f => f.relativePath)).toEqual(['text.txt']);

src/fileOperations.ts

@@ -1,6 +1,7 @@
 import * as vscode from 'vscode';
 import * as path from 'path';
 import * as fs from 'fs/promises';
+import { createReadStream } from 'fs';
 import { FileInfo, DirectoryInfo, ScanOptions } from './types/fileTypes';
 import { minimatch } from 'minimatch';
 import { DirectoryNotFoundError, FileSizeLimitError, ScanError } from './errors/errors';
@@ -129,6 +130,16 @@ export class FileOperations {
         this.currentSelectedPath = path;
     }
 
+    private async readFileContentStream(filePath: string): Promise<string> {
+        return new Promise((resolve, reject) => {
+            let data = '';
+            const stream = createReadStream(filePath, { encoding: 'utf-8' });
+            stream.on('data', chunk => { data += chunk; });
+            stream.on('end', () => resolve(data));
+            stream.on('error', err => reject(err));
+        });
+    }
+
     async scanDirectory(targetPath: string, options: ScanOptions): Promise<DirectoryInfo> {
         try {
             // .gitignoreパターンを読み込む（初回のみ）
@@ -156,8 +167,8 @@ export class FileOperations {
                 }
 
                 // バイナリファイルのチェック
-                const buffer = await fs.readFile(absolutePath);
-                if (isBinaryFile(buffer)) {
+                const content = await this.readFileContentStream(absolutePath);
+                if (isBinaryFile(content)) {
                     this.logger.info(`バイナリファイルをスキップ: ${relativePath}`);
                     return {
                         uri: vscode.Uri.file(path.dirname(absolutePath)),
@@ -167,7 +178,6 @@ export class FileOperations {
                     };
                 }
 
-                const content = buffer.toString('utf-8');
                 const language = this.detectLanguage(path.basename(absolutePath));
                 let imports: string[] | undefined;
                 if (options.includeDependencies) {
@@ -231,13 +241,12 @@ export class FileOperations {
                         }
 
                         // バイナリファイルのチェック
-                        const buffer = await fs.readFile(entryPath);
-                        if (isBinaryFile(buffer)) {
+                        const content = await this.readFileContentStream(entryPath);
+                        if (isBinaryFile(content)) {
                             this.logger.info(`バイナリファイルをスキップ: ${entryRelativePath}`);
                             continue;
                         }
 
-                        const content = buffer.toString('utf-8');
                         const language = this.detectLanguage(entryNameString);
                         let imports: string[] | undefined;
                         if (options.includeDependencies) {