From 871a9c49b368fcd0edacbf100ffa67a1b180dd69 Mon Sep 17 00:00:00 2001
From: Neil <4138956+nwparker@users.noreply.github.com>
Date: Sat, 30 May 2026 05:15:27 -0700
Subject: [PATCH] fix: append large workspace history safely

---
 .../worktree-ownership-large-history.test.ts  | 25 +++++++++++++++++++
 src/shared/worktree-ownership.ts              | 15 +++++++++--
 2 files changed, 38 insertions(+), 2 deletions(-)
 create mode 100644 src/shared/worktree-ownership-large-history.test.ts

diff --git a/src/shared/worktree-ownership-large-history.test.ts b/src/shared/worktree-ownership-large-history.test.ts
new file mode 100644
index 00000000000..36fb5df60e2
--- /dev/null
+++ b/src/shared/worktree-ownership-large-history.test.ts
@@ -0,0 +1,25 @@
+import { describe, expect, it } from 'vitest'
+import type { GlobalSettings, Repo } from './types'
+import { buildKnownOrcaWorkspaceLayouts } from './worktree-ownership'
+
+describe('buildKnownOrcaWorkspaceLayouts', () => {
+  it('handles workspace directory history larger than the JavaScript argument limit', () => {
+    const workspaceDirHistory = Array.from({ length: 130_000 }, (_, index) => ({
+      path: `/old/workspaces/${index}`,
+      nestWorkspaces: index % 2 === 0
+    }))
+    const settings = {
+      workspaceDir: '/orca/workspaces',
+      nestWorkspaces: true,
+      workspaceDirHistory
+    } satisfies Pick<GlobalSettings, 'workspaceDir' | 'nestWorkspaces' | 'workspaceDirHistory'>
+    const repo = {
+      path: '/repos/app'
+    } satisfies Pick<Repo, 'path' | 'connectionId'>
+
+    const layouts = buildKnownOrcaWorkspaceLayouts(settings, repo)
+
+    expect(layouts).toHaveLength(workspaceDirHistory.length + 1)
+    expect(layouts.at(-1)).toEqual({ path: '/old/workspaces/129999', nestWorkspaces: false })
+  })
+})
diff --git a/src/shared/worktree-ownership.ts b/src/shared/worktree-ownership.ts
index c628ed14202..a2a1d2eb52a 100644
--- a/src/shared/worktree-ownership.ts
+++ b/src/shared/worktree-ownership.ts
@@ -49,11 +49,11 @@ export function buildKnownOrcaWorkspaceLayouts(
   const layouts: OrcaWorkspaceLayout[] = []
   if (!repo?.connectionId && settings.workspaceDir) {
     layouts.push({ path: settings.workspaceDir, nestWorkspaces: settings.nestWorkspaces })
-    layouts.push(...(settings.workspaceDirHistory ?? []))
+    appendWorkspaceLayouts(layouts, settings.workspaceDirHistory ?? [])
   }
 
   const wslLayouts = repo ? buildWslWorkspaceLayouts(repo.path, settings) : []
-  layouts.push(...wslLayouts)
+  appendWorkspaceLayouts(layouts, wslLayouts)
 
   const seen = new Set<string>()
   return layouts.filter((layout) => {
@@ -66,6 +66,17 @@ export function buildKnownOrcaWorkspaceLayouts(
   })
 }
 
+function appendWorkspaceLayouts(
+  target: OrcaWorkspaceLayout[],
+  source: readonly OrcaWorkspaceLayout[]
+): void {
+  // Why: persisted workspace history is unbounded; using push(...source) can
+  // exceed V8's argument limit before ownership classification can recover.
+  for (const layout of source) {
+    target.push(layout)
+  }
+}
+
 function buildWslWorkspaceLayouts(
   repoPath: string,
   settings: Pick<GlobalSettings, 'nestWorkspaces' | 'workspaceDirHistory'>