perf: dedupe VS Code git read execs

Reduce duplicate git rev-parse work in VS Code Cache only safe git read commands Add VS Code bridge cache coverage
2026-05-25 12:55:59 +03:00
parent f8beffce32
commit 1b141b17da
2 changed files with 202 additions and 18 deletions
@@ -0,0 +1,88 @@
+import { beforeEach, describe, expect, it, mock } from 'bun:test';
+import { promisify } from 'node:util';
+
+const execCalls = [];
+const execMock = mock(() => {
+  throw new Error('exec should be called through promisify');
+});
+
+execMock[promisify.custom] = (command, options) => {
+  execCalls.push({ command, options });
+  return new Promise((resolve) => {
+    setTimeout(() => {
+      resolve({ stdout: '/repo/.git\n/repo/.git\n', stderr: '' });
+    }, 10);
+  });
+};
+
+mock.module('child_process', () => ({
+  exec: execMock,
+}));
+
+mock.module('vscode', () => ({
+  workspace: {
+    workspaceFolders: [{ uri: { fsPath: '/workspace' } }],
+    fs: {},
+  },
+  Uri: {
+    file: (fsPath) => ({ fsPath }),
+  },
+  FileType: {
+    Directory: 2,
+  },
+  window: {},
+}));
+
+const { clearGitReadCacheForTests, handleFsBridgeMessage } = await import('./bridge-fs-runtime');
+
+const deps = {
+  resolveUserPath: (value) => value,
+  listDirectoryEntries: mock(),
+  normalizeFsPath: (value) => value,
+  execGit: mock(),
+  searchDirectory: mock(),
+  resolveFileReadPath: mock(),
+  parseDroppedFileReference: mock(),
+  readUriAsAttachment: mock(),
+};
+
+describe('bridge fs exec git read cache', () => {
+  beforeEach(() => {
+    execCalls.length = 0;
+    clearGitReadCacheForTests();
+  });
+
+  it('dedupes in-flight cacheable git reads and reuses fresh results', async () => {
+    const command = 'git rev-parse --absolute-git-dir --git-common-dir';
+    const cwd = '/repo';
+
+    const [first, second] = await Promise.all([
+      handleFsBridgeMessage({ id: '1', type: 'api:fs:exec', payload: { commands: [command], cwd } }, deps),
+      handleFsBridgeMessage({ id: '2', type: 'api:fs:exec', payload: { commands: [command], cwd } }, deps),
+    ]);
+
+    expect(first?.success).toBe(true);
+    expect(second?.success).toBe(true);
+    expect(execCalls).toHaveLength(1);
+
+    const spacedCommand = 'git   rev-parse   --absolute-git-dir   --git-common-dir';
+    const cached = await handleFsBridgeMessage({ id: '3', type: 'api:fs:exec', payload: { commands: [spacedCommand], cwd } }, deps);
+
+    expect(execCalls).toHaveLength(1);
+    expect(cached?.data?.results?.[0]).toMatchObject({
+      command: spacedCommand,
+      success: true,
+      stdout: '/repo/.git\n/repo/.git',
+    });
+  });
+
+  it('does not cache arbitrary exec commands', async () => {
+    const command = 'git status --porcelain';
+    const cwd = '/repo';
+
+    await handleFsBridgeMessage({ id: '1', type: 'api:fs:exec', payload: { commands: [command], cwd } }, deps);
+    await handleFsBridgeMessage({ id: '2', type: 'api:fs:exec', payload: { commands: [command], cwd } }, deps);
+
+    expect(execCalls).toHaveLength(2);
+  });
+});