`.watchman-cookie-*` files in git worktrees cause periodic `/vcs/diff` requests

[jasonyork]

Description

When using secondary workspaces (git worktrees), .watchman-cookie-* files created by Watchman at the worktree root trigger the file watcher. This leads to frequent refreshVcs() calls and periodic requests to /vcs/diff.

This can be annoying when attempting to comment on the code because the file will refresh, losing anything typed in the comment.

Root cause(s)

1. .watchman-cookie-* files are not ignored by default (they likely should be).
2. The watcher.ignore config option is only applied to the project directory subscription, not to the .git directory subscription used for worktrees.

Proposed Fix

Update packages/opencode/src/file/watcher.ts to apply config ignores to the VCS directory subscription:

// Currently:
yield* subscribe(vcsDir, ignore)

// Should be:
yield* subscribe(vcsDir, [...ignore, ...cfgIgnores])
Additionally, add .watchman-cookie-* to the default ignore patterns in src/file/ignore.ts.

Workaround

Disabling the watcher with OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER=true

Plugins

obra/superpowers

OpenCode version

1.14.23

Steps to reproduce

1. Use a project with "workspaces" enabled (secondary git worktree).
2. Let Watchman run (creates .watchman-cookie-* files in the secondary worktree root).
3. Observe periodic /vcs/diff requests in network tab or server logs.

Screenshot and/or share link

No response

Operating System

macOS Tahoe 26.4.1

Terminal

iTerm2

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• fix: review panel flickers/rerenders on every filesystem event including ignored paths #21452: Describes the same root cause — events from worktree and git-dir subscriptions not being filtered through ignore patterns, leading to spurious refreshVcs() calls. The fix described there includes moving ignore filtering into each subscription and handling git-dir worktree paths properly, which overlaps significantly with the fix proposed here.
• watcher.ignore in opencode.json does not prevent hang in non-git dirs with large subtrees #23190: Related issue where watcher.ignore config is not applied to the underlying watch setup, causing ignore patterns to be ineffective — similar to the second root cause described here.

It may be worth coordinating with the authors/assignees of those issues before implementing a separate fix.