fix(tmux): run tmux CLI from stable cwd and verify pane starts in workspace#2984
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harshitsinghbhandari wants to merge 1 commit into
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fix(tmux): run tmux CLI from stable cwd and verify pane starts in workspace#2984harshitsinghbhandari wants to merge 1 commit into
harshitsinghbhandari wants to merge 1 commit into
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…kspace The first tmux CLI call after daemon boot auto-starts the persistent tmux server, which inherits and keeps the daemon's own cwd. After a Squirrel/ShipIt auto-update that cwd can be a deleted staging dir; tmux then silently falls back to the server cwd whenever new-session -c cannot resolve, stranding worker panes in a deleted directory and killing agents with a context-free Bun ENOENT (issue #2775, root-caused by inode matching). - execRunner.Run now sets cmd.Dir to os.TempDir() so the tmux server is never pinned to a path an app update can delete. - Create verifies the pane's #{pane_current_path} matches cfg.WorkspacePath (symlink-resolved, so macOS /var vs /private/var compares equal) and fails with an error naming both paths instead of leaving the silent fallback. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Summary
Fixes the tmux poisoned-cwd bug that strands worker panes in deleted ShipIt directories (root-caused live by inode matching; related: #2775).
Root cause.
execRunner.Runcalledexec.CommandContextwithout settingcmd.Dir, so every tmux CLI invocation inherited the daemon's own cwd. The first tmux call after boot auto-starts the persistent tmux server, permanently pinning the server's cwd to whatever the daemon had. After a Squirrel/ShipIt auto-update that can be a staging dir that gets deleted (observed:/var/folders/.../ShipIt.zThlb2VO/...app/Contents/Resources; even the healthy case is the app bundle Resources dir, which ShipIt swaps every update). tmux has a silent fallback: whennew-session -c <dir>cannot be resolved at spawn time, the pane starts in the server's cwd instead of erroring. A session hit that fallback and its agent died with a context-freeENOENT: Bun could not find a fileplus shell-init getcwd errors.Reproduced on a scratch tmux socket:
tmux new-session -d -c <deleted-dir>exits 0 and the pane silently starts elsewhere;display-message -p '#{pane_current_path}'exposes the mismatch.Changes
execRunner.Runnow setscmd.Dir = os.TempDir(), so the auto-started tmux server is never pinned to a path an app update can delete. (tmux.Newis constructed config-free inruntimeselect, so the temp dir is the clean stable choice over plumbing the data dir through.)Createnow verifies the pane's#{pane_current_path}matchescfg.WorkspacePathafter the liveness check, resolving symlinks so macOS/varvs/private/varcompares equal. On mismatch it destroys the session and fails with an error naming both paths and pointing at the server-cwd fallback, replacing today's silent fallback plus downstream raw ENOENT.displayPaneCwdArgsbuilder incommands.go, following the existing arg-builder pattern.Tests
TestCreateFailsLoudlyWhenPaneCwdMismatches(fake runner reports a pane cwd that is not the workspace; asserts loud error naming both paths + kill-session cleanup),TestSamePathResolvesSymlinks,TestExecRunnerRunsFromStableDir.TestCommandBuildersand the existingCreatetests for the new sixth call.gofmt(clean),go vet,go build ./...,go test ./internal/adapters/runtime/tmux/(42 pass, including the real-tmux integration tests, which now exercise the verification through macOS/varaliasing end to end).go test ./...: 4 pre-existinginternal/clispawn-test failures reproduce identically on cleanupstream/mainon this machine (live AO daemon state interferes); unrelated to this change.Risks / follow-ups
Create.IsAliveandSendMessagedeliberately do not probe pane cwd in this PR (kept minimal per scope); a follow-up could add a cwd probe to the reaper path to catch a server whose panes were poisoned before this fix shipped.Createnow fails where it previously "succeeded" with a doomed pane. That is the intended behavior change: a loud, actionable error instead of a stranded agent.🤖 Generated with Claude Code