fix: preserve large relay bulk discard matches

src/relay/git-handler.test.ts

@@ -17,17 +17,18 @@ import {
   type MockDispatcher,
   type RelayDispatcher
 } from './git-handler-test-setup'
+import type { GitExec } from './git-handler-ops'
 
 describe('GitHandler', () => {
   let dispatcher: MockDispatcher
   let tmpDir: string
+  let handler: GitHandler
 
   beforeEach(() => {
     tmpDir = mkdtempSync(path.join(tmpdir(), 'relay-git-'))
     dispatcher = createMockDispatcher()
     const ctx = new RelayContext()
-    // eslint-disable-next-line no-new
-    new GitHandler(dispatcher as unknown as RelayDispatcher, ctx)
+    handler = new GitHandler(dispatcher as unknown as RelayDispatcher, ctx)
   })
 
   afterEach(async () => {
@@ -498,6 +499,32 @@ describe('GitHandler', () => {
       await expect(fs.access(path.join(tmpDir, 'new.txt'))).rejects.toThrow()
     })
 
+    it('bulk discards a tracked directory with a very large tracked child list', async () => {
+      const trackedOutput = `${Array.from(
+        { length: 130_000 },
+        (_, index) => `src/generated/file-${index}.ts`
+      ).join('\0')}\0`
+      const git = vi.fn<GitExec>(async (args) => {
+        if (args[0] === 'ls-files') {
+          return { stdout: trackedOutput, stderr: '' }
+        }
+        return { stdout: '', stderr: '' }
+      })
+      ;(handler as unknown as { git: GitExec }).git = git
+
+      await expect(
+        dispatcher.callRequest('git.bulkDiscard', {
+          worktreePath: tmpDir,
+          filePaths: ['src']
+        })
+      ).resolves.toBeUndefined()
+
+      expect(git).toHaveBeenCalledWith(
+        ['restore', '--worktree', '--source=HEAD', '--', ':(literal)src'],
+        tmpDir
+      )
+    })
+
     it('rejects path traversal', async () => {
       gitInit(tmpDir)
       await expect(

src/relay/git-handler.ts

@@ -276,7 +276,13 @@ export class GitHandler {
         ['ls-files', '-z', '--', ...chunk.map((p) => this.literalPathspec(p))],
         worktreePath
       )
-      trackedPathSpecs.push(...stdout.split('\0').filter(Boolean))
+      // Why: selecting a tracked directory can expand to more child paths than
+      // V8 allows as function arguments.
+      for (const trackedPath of stdout.split('\0')) {
+        if (trackedPath) {
+          trackedPathSpecs.push(trackedPath)
+        }
+      }
     }
 
     const trackedPaths = filePaths.filter((filePath) =>