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Fix shell integration idle HEAD-change polling #1702

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lawrencecchen wants to merge 3 commits into from
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Fix shell integration idle HEAD-change polling #1702

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5c1caf0
Add idle HEAD-change PR polling regression test
lawrencecchen Mar 18, 2026
bb0c2d9
Fix shell integration idle HEAD-change polling
lawrencecchen Mar 18, 2026
2a28c98
Merge remote-tracking branch 'origin/main' into ci-refresh-1702
lawrencecchen Mar 25, 2026
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143 changes: 91 additions & 52 deletions Resources/shell-integration/cmux-bash-integration.bash
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -180,7 +180,7 @@ _cmux_tmux_sync_cmux_environment() {

_cmux_git_resolve_head_path() {
# Resolve the HEAD file path without invoking git (fast; works for worktrees).
local dir="$PWD"
local dir="${1:-$PWD}"
while :; do
if [[ -d "$dir/.git" ]]; then
printf '%s\n' "$dir/.git/HEAD"
Expand Down Expand Up @@ -213,6 +213,57 @@ _cmux_git_head_signature() {
printf '%s\n' "$line"
}

_cmux_update_git_head_tracking() {
local repo_path="${1:-$PWD}"
if [[ "$repo_path" != "$_CMUX_GIT_HEAD_LAST_PWD" ]]; then
_CMUX_GIT_HEAD_LAST_PWD="$repo_path"
_CMUX_GIT_HEAD_PATH="$(_cmux_git_resolve_head_path "$repo_path" 2>/dev/null || true)"
_CMUX_GIT_HEAD_SIGNATURE=""
fi

[[ -n "$_CMUX_GIT_HEAD_PATH" ]] || return 1

local head_signature
head_signature="$(_cmux_git_head_signature "$_CMUX_GIT_HEAD_PATH" 2>/dev/null || true)"
[[ -n "$head_signature" ]] || return 1

if [[ -z "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
# The first observed HEAD value is just the session baseline.
# Treating it as a branch change clears restore-seeded PR badges
# before the first background probe can confirm the current PR.
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
return 1
fi

if [[ "$head_signature" != "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
return 0
fi

return 1
}

_cmux_report_git_branch_for_path() {
local repo_path="$1"
[[ -n "$repo_path" ]] || return 0
[[ -S "$CMUX_SOCKET_PATH" ]] || return 0
[[ -n "$CMUX_TAB_ID" ]] || return 0
[[ -n "$CMUX_PANEL_ID" ]] || return 0

# Skip git operations if not in a git repository to avoid TCC prompts
git -C "$repo_path" rev-parse --git-dir >/dev/null 2>&1 || return 0

local branch dirty_opt="" first
branch="$(git -C "$repo_path" branch --show-current 2>/dev/null)"
if [[ -n "$branch" ]]; then
first="$(git -C "$repo_path" status --porcelain -uno 2>/dev/null | head -1)"
[[ -n "$first" ]] && dirty_opt="--status=dirty"
_cmux_send "report_git_branch $branch $dirty_opt --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
else
_cmux_send "clear_git_branch --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
fi
}

_cmux_report_tty_payload() {
[[ -n "$CMUX_TAB_ID" ]] || return 0
[[ -n "$_CMUX_TTY_NAME" ]] || return 0
Expand Down Expand Up @@ -412,35 +463,44 @@ _cmux_kill_process_tree() {
kill "-$signal" "$pid" >/dev/null 2>&1 || true
}

_cmux_start_probe_timeout_watchdog() {
local probe_pid="$1"
local timeout="${2:-0}"
[[ -n "$probe_pid" ]] || return 1
(( timeout > 0 )) || return 1

(
sleep "$timeout"
kill -0 "$probe_pid" >/dev/null 2>&1 || exit 0
_cmux_kill_process_tree "$probe_pid" KILL
) >/dev/null 2>&1 &

printf '%s\n' "$!"
}

_cmux_stop_probe_timeout_watchdog() {
local watchdog_pid="$1"
[[ -n "$watchdog_pid" ]] || return 0
_cmux_kill_process_tree "$watchdog_pid" KILL
wait "$watchdog_pid" >/dev/null 2>&1 || true
}

_cmux_run_pr_probe_with_timeout() {
local repo_path="$1"
local probe_pid=""
local started_at=$SECONDS
local now=$started_at
local watchdog_pid=""

(
_cmux_report_pr_for_path "$repo_path"
) &
probe_pid=$!

while kill -0 "$probe_pid" >/dev/null 2>&1; do
sleep 1
now=$SECONDS
if (( _CMUX_ASYNC_JOB_TIMEOUT > 0 )) && (( now - started_at >= _CMUX_ASYNC_JOB_TIMEOUT )); then
_cmux_kill_process_tree "$probe_pid" TERM
sleep 0.2
if kill -0 "$probe_pid" >/dev/null 2>&1; then
_cmux_kill_process_tree "$probe_pid" KILL
sleep 0.2
fi
if ! kill -0 "$probe_pid" >/dev/null 2>&1; then
wait "$probe_pid" >/dev/null 2>&1 || true
fi
return 1
fi
done
watchdog_pid="$(_cmux_start_probe_timeout_watchdog "$probe_pid" "$_CMUX_ASYNC_JOB_TIMEOUT" 2>/dev/null || true)"

wait "$probe_pid"
local probe_status=$?
_cmux_stop_probe_timeout_watchdog "$watchdog_pid"
return "$probe_status"
}

_cmux_stop_pr_poll_loop() {
Expand Down Expand Up @@ -473,6 +533,13 @@ _cmux_start_pr_poll_loop() {
{
while :; do
kill -0 "$watch_shell_pid" 2>/dev/null || break
if _cmux_update_git_head_tracking "$watch_pwd"; then
_CMUX_PR_FORCE=1
_cmux_clear_pr_for_panel
Comment thread
coderabbitai[bot] marked this conversation as resolved.
{
_cmux_report_git_branch_for_path "$watch_pwd"
} >/dev/null 2>&1 &
fi
_cmux_run_pr_probe_with_timeout "$watch_pwd" || true
sleep "$interval"
done
Expand Down Expand Up @@ -554,27 +621,10 @@ _cmux_prompt_command() {
# Branch can change via aliases/tools while an older probe is still in flight.
# Track .git/HEAD content so we can restart stale probes immediately.
local git_head_changed=0
if [[ "$pwd" != "$_CMUX_GIT_HEAD_LAST_PWD" ]]; then
_CMUX_GIT_HEAD_LAST_PWD="$pwd"
_CMUX_GIT_HEAD_PATH="$(_cmux_git_resolve_head_path 2>/dev/null || true)"
_CMUX_GIT_HEAD_SIGNATURE=""
fi
if [[ -n "$_CMUX_GIT_HEAD_PATH" ]]; then
local head_signature
head_signature="$(_cmux_git_head_signature "$_CMUX_GIT_HEAD_PATH" 2>/dev/null || true)"
if [[ -n "$head_signature" ]]; then
if [[ -z "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
# The first observed HEAD value is just the session baseline.
# Treating it as a branch change clears restore-seeded PR badges
# before the first background probe can confirm the current PR.
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
elif [[ "$head_signature" != "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
git_head_changed=1
# Also invalidate the PR poller so it refreshes with the new branch.
_CMUX_PR_FORCE=1
fi
fi
if _cmux_update_git_head_tracking "$pwd"; then
git_head_changed=1
# Also invalidate the PR poller so it refreshes with the new branch.
_CMUX_PR_FORCE=1
fi

# Git branch/dirty can change without a directory change (e.g. `git checkout`),
Expand All @@ -593,18 +643,7 @@ _cmux_prompt_command() {
_CMUX_GIT_LAST_PWD="$pwd"
_CMUX_GIT_LAST_RUN=$now
{
# Skip git operations if not in a git repository to avoid TCC prompts
git rev-parse --git-dir >/dev/null 2>&1 || return 0
local branch dirty_opt=""
branch=$(git branch --show-current 2>/dev/null)
if [[ -n "$branch" ]]; then
local first
first=$(git status --porcelain -uno 2>/dev/null | head -1)
[[ -n "$first" ]] && dirty_opt="--status=dirty"
_cmux_send "report_git_branch $branch $dirty_opt --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
else
_cmux_send "clear_git_branch --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
fi
_cmux_report_git_branch_for_path "$pwd"
} >/dev/null 2>&1 &
_CMUX_GIT_JOB_PID=$!
disown
Expand Down
116 changes: 73 additions & 43 deletions Resources/shell-integration/cmux-zsh-integration.zsh
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -277,7 +277,7 @@ _cmux_install_winch_guard

_cmux_git_resolve_head_path() {
# Resolve the HEAD file path without invoking git (fast; works for worktrees).
local dir="$PWD"
local dir="${1:-$PWD}"
while true; do
if [[ -d "$dir/.git" ]]; then
print -r -- "$dir/.git/HEAD"
Expand Down Expand Up @@ -313,6 +313,36 @@ _cmux_git_head_signature() {
return 1
}

_cmux_update_git_head_tracking() {
local repo_path="${1:-$PWD}"
if [[ "$repo_path" != "$_CMUX_GIT_HEAD_LAST_PWD" ]]; then
_CMUX_GIT_HEAD_LAST_PWD="$repo_path"
_CMUX_GIT_HEAD_PATH="$(_cmux_git_resolve_head_path "$repo_path" 2>/dev/null || true)"
_CMUX_GIT_HEAD_SIGNATURE=""
fi

[[ -n "$_CMUX_GIT_HEAD_PATH" ]] || return 1

local head_signature=""
head_signature="$(_cmux_git_head_signature "$_CMUX_GIT_HEAD_PATH" 2>/dev/null || true)"
[[ -n "$head_signature" ]] || return 1

if [[ -z "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
# The first observed HEAD value establishes the baseline for this shell
# session/context. Don't treat it as a branch change or we'll clear
# restore-seeded PR badges before the first background probe runs.
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
return 1
fi

if [[ "$head_signature" != "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
return 0
fi

return 1
}

_cmux_report_tty_payload() {
[[ -n "$CMUX_TAB_ID" ]] || return 0
[[ -n "$_CMUX_TTY_NAME" ]] || return 0
Expand Down Expand Up @@ -534,35 +564,44 @@ _cmux_kill_process_tree() {
kill "-$signal" "$pid" >/dev/null 2>&1 || true
}

_cmux_start_probe_timeout_watchdog() {
local probe_pid="$1"
local timeout="${2:-0}"
[[ -n "$probe_pid" ]] || return 1
(( timeout > 0 )) || return 1

(
sleep "$timeout"
kill -0 "$probe_pid" >/dev/null 2>&1 || exit 0
_cmux_kill_process_tree "$probe_pid" KILL
) >/dev/null 2>&1 &

print -r -- "$!"
}

_cmux_stop_probe_timeout_watchdog() {
local watchdog_pid="$1"
[[ -n "$watchdog_pid" ]] || return 0
_cmux_kill_process_tree "$watchdog_pid" KILL
wait "$watchdog_pid" >/dev/null 2>&1 || true
}

_cmux_run_pr_probe_with_timeout() {
local repo_path="$1"
local probe_pid=""
local started_at=$EPOCHSECONDS
local now=$started_at
local watchdog_pid=""

(
_cmux_report_pr_for_path "$repo_path"
) &
probe_pid=$!

while kill -0 "$probe_pid" >/dev/null 2>&1; do
sleep 1
now=$EPOCHSECONDS
if (( _CMUX_ASYNC_JOB_TIMEOUT > 0 )) && (( now - started_at >= _CMUX_ASYNC_JOB_TIMEOUT )); then
_cmux_kill_process_tree "$probe_pid" TERM
sleep 0.2
if kill -0 "$probe_pid" >/dev/null 2>&1; then
_cmux_kill_process_tree "$probe_pid" KILL
sleep 0.2
fi
if ! kill -0 "$probe_pid" >/dev/null 2>&1; then
wait "$probe_pid" >/dev/null 2>&1 || true
fi
return 1
fi
done
watchdog_pid="$(_cmux_start_probe_timeout_watchdog "$probe_pid" "$_CMUX_ASYNC_JOB_TIMEOUT" 2>/dev/null || true)"

@cubic-dev-ai cubic-dev-ai Bot Mar 18, 2026 •
edited
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P1: Starting the timeout watchdog via command substitution can detach it from the poll-loop lifecycle, leaving a stale watchdog that may later SIGKILL a reused PID.

Prompt for AI agents 
Check if this issue is valid — if so, understand the root cause and fix it. At Resources/shell-integration/cmux-zsh-integration.zsh, line 459:

<comment>Starting the timeout watchdog via command substitution can detach it from the poll-loop lifecycle, leaving a stale watchdog that may later SIGKILL a reused PID.</comment>

<file context>
@@ -394,35 +424,44 @@ _cmux_kill_process_tree() {
-            return 1
-        fi
-    done
+    watchdog_pid="$(_cmux_start_probe_timeout_watchdog "$probe_pid" "$_CMUX_ASYNC_JOB_TIMEOUT" 2>/dev/null || true)"
 
     wait "$probe_pid"
</file context>
Fix with Cubic


wait "$probe_pid"
local probe_status=$?
_cmux_stop_probe_timeout_watchdog "$watchdog_pid"
return "$probe_status"
}

_cmux_stop_pr_poll_loop() {
Expand Down Expand Up @@ -595,6 +634,14 @@ _cmux_start_pr_poll_loop() {
{
while true; do
kill -0 "$watch_shell_pid" >/dev/null 2>&1 || break
if _cmux_update_git_head_tracking "$watch_pwd"; then
_CMUX_GIT_FORCE=1
_CMUX_PR_FORCE=1
_cmux_clear_pr_for_panel
{
_cmux_report_git_branch_for_path "$watch_pwd"
} >/dev/null 2>&1 &!
fi
_cmux_run_pr_probe_with_timeout "$watch_pwd" || true
sleep "$interval"
done
Expand Down Expand Up @@ -732,30 +779,13 @@ _cmux_precmd() {

# Git branch can change without a `git ...`-prefixed command (aliases like `gco`,
# tools like `gh pr checkout`, etc.). Detect HEAD changes and force a refresh.
if [[ "$pwd" != "$_CMUX_GIT_HEAD_LAST_PWD" ]]; then
_CMUX_GIT_HEAD_LAST_PWD="$pwd"
_CMUX_GIT_HEAD_PATH="$(_cmux_git_resolve_head_path 2>/dev/null || true)"
_CMUX_GIT_HEAD_SIGNATURE=""
fi
if [[ -n "$_CMUX_GIT_HEAD_PATH" ]]; then
local head_signature
head_signature="$(_cmux_git_head_signature "$_CMUX_GIT_HEAD_PATH" 2>/dev/null || true)"
if [[ -n "$head_signature" ]]; then
if [[ -z "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
# The first observed HEAD value establishes the baseline for this
# shell session. Don't treat it as a branch change or we'll clear
# restore-seeded PR badges before the first background probe runs.
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
elif [[ "$head_signature" != "$_CMUX_GIT_HEAD_SIGNATURE" ]]; then
_CMUX_GIT_HEAD_SIGNATURE="$head_signature"
git_head_changed=1
# Treat HEAD file change like a git command — force-replace any
# running probe so the sidebar picks up the new branch immediately.
_CMUX_GIT_FORCE=1
_CMUX_PR_FORCE=1
should_git=1
fi
fi
if _cmux_update_git_head_tracking "$pwd"; then
git_head_changed=1
# Treat HEAD file change like a git command — force-replace any
# running probe so the sidebar picks up the new branch immediately.
_CMUX_GIT_FORCE=1
_CMUX_PR_FORCE=1
should_git=1
fi

if [[ "$pwd" != "$_CMUX_GIT_LAST_PWD" ]]; then
Expand Down
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