From 30a47f47f074142088874b3efbdef7b429202aec Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 19:02:59 +0100
Subject: [PATCH 1/7] test: terminate wheel test background jobs reliably

---
 test-wheel.bash | 115 ++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 97 insertions(+), 18 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index f68e3d2..c00d39d 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-set -e
+set -euo pipefail
 
 venv_python="${PYTHON_WHEEL_TEST_EXECUTABLE:-}"
 if [[ -z "$venv_python" ]]; then
@@ -29,33 +29,110 @@ python -m pip install -U pip
 pip install pytest
 
 cleanup=true
+background_pids=()
+failed_pids=()
+cleanup_done=false
 
-trap '
-  failed_pids=()
-  for pid in $(jobs -p); do
-    if kill -0 $pid >/dev/null 2>&1; then
-      # Background process is still running - kill it.
-      kill $pid
+is_windows_shell=false
+case "${OSTYPE:-}" in
+  msys*|cygwin*)
+    is_windows_shell=true
+    ;;
+esac
+if [[ "${OS:-}" == "Windows_NT" ]]; then
+  is_windows_shell=true
+fi
+
+terminate_pid_tree() {
+  local pid="$1"
+
+  if ! kill -0 "$pid" >/dev/null 2>&1; then
+    return 0
+  fi
+
+  if [[ "$is_windows_shell" == true ]] && command -v taskkill >/dev/null 2>&1; then
+    taskkill //PID "$pid" //T //F >/dev/null 2>&1 || true
+  else
+    kill -TERM "-$pid" >/dev/null 2>&1 || kill "$pid" >/dev/null 2>&1 || true
+  fi
+
+  local deadline=$((SECONDS + 20))
+  while kill -0 "$pid" >/dev/null 2>&1; do
+    if (( SECONDS >= deadline )); then
+      if [[ "$is_windows_shell" == true ]] && command -v taskkill >/dev/null 2>&1; then
+        taskkill //PID "$pid" //T //F >/dev/null 2>&1 || true
+      else
+        kill -KILL "-$pid" >/dev/null 2>&1 || kill -9 "$pid" >/dev/null 2>&1 || true
+      fi
+      break
+    fi
+    sleep 1
+  done
+
+  wait "$pid" 2>/dev/null || true
+}
+
+run_command() {
+  local cmd="$1"
+  if [[ "$cmd" == *.py ]] && [[ "$cmd" != *[[:space:]]* ]]; then
+    python "$cmd"
+  else
+    bash -lc "$cmd"
+  fi
+}
+
+launch_background_command() {
+  local cmd="$1"
+  if [[ "$is_windows_shell" == true ]]; then
+    bash -lc "$cmd" &
+  elif command -v setsid >/dev/null 2>&1; then
+    setsid bash -lc "$cmd" &
+  else
+    bash -lc "$cmd" &
+  fi
+}
+
+cleanup_background_jobs() {
+  local pid=""
+  for pid in "${background_pids[@]}"; do
+    if kill -0 "$pid" >/dev/null 2>&1; then
+      terminate_pid_tree "$pid"
     else
-      exit_status=$?
-      if [[ $exit_status -eq 0 ]]; then
+      if wait "$pid"; then
         echo "Background task $pid already exited with zero status."
       else
+        local exit_status=$?
         echo "Background task $pid exited with nonzero status ($exit_status)."
         failed_pids+=("$pid")
       fi
     fi
   done
+}
 
+cleanup_virtualenv() {
   if [[ "$cleanup" == "true" ]]; then
-    echo "→ Removing $venv"; rm -rf "$venv"
+    echo "→ Removing $venv"
+    rm -rf "$venv"
   fi
+}
+
+on_exit() {
+  if [[ "$cleanup_done" == "true" ]]; then
+    return 0
+  fi
+  cleanup_done=true
+  set +e
+  cleanup_background_jobs
+  cleanup_virtualenv
 
   if [[ ${#failed_pids[@]} -gt 0 ]]; then
     echo "The following background processes exited with nonzero status: ${failed_pids[@]}"
-    exit 1
+    return 1
   fi
-  ' EXIT
+  return 0
+}
+
+trap on_exit EXIT
 
 while [[ $# -gt 0 ]]; do
   case $1 in
@@ -67,7 +144,8 @@ while [[ $# -gt 0 ]]; do
       ;;
     -b|--background)
       echo "→ Launching background task: $2"
-      $2 &
+      launch_background_command "$2"
+      background_pids+=("$!")
       echo "... started with PID: $!"
       sleep 5
       shift
@@ -75,11 +153,7 @@ while [[ $# -gt 0 ]]; do
       ;;
     -f|--foreground)
       echo "→ Starting foreground task: $2"
-      if [[ "$2" == *.py ]] && [[ "$2" != *[[:space:]]* ]]; then
-        python "$2"
-      else
-        $2
-      fi
+      run_command "$2"
       shift
       shift
       ;;
@@ -91,3 +165,8 @@ while [[ $# -gt 0 ]]; do
       ;;
   esac
 done
+
+cleanup_status=0
+on_exit || cleanup_status=$?
+trap - EXIT
+exit "$cleanup_status"

From 358e836c764baec56edd2193223a4cc5ce08e50a Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 19:39:23 +0100
Subject: [PATCH 2/7] test: preserve deferred args in wheel harness

---
 test-wheel.bash | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index c00d39d..a1d1b66 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -77,18 +77,18 @@ run_command() {
   if [[ "$cmd" == *.py ]] && [[ "$cmd" != *[[:space:]]* ]]; then
     python "$cmd"
   else
-    bash -lc "$cmd"
+    $cmd
   fi
 }
 
 launch_background_command() {
   local cmd="$1"
   if [[ "$is_windows_shell" == true ]]; then
-    bash -lc "$cmd" &
+    $cmd &
   elif command -v setsid >/dev/null 2>&1; then
-    setsid bash -lc "$cmd" &
+    setsid $cmd &
   else
-    bash -lc "$cmd" &
+    $cmd &
   fi
 }
 

From dd51812616afbfd8563849576138d36cc8c28fc5 Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 19:53:36 +0100
Subject: [PATCH 3/7] bash: support empty background jobs on macOS

---
 test-wheel.bash | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index a1d1b66..d7a60e2 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -94,7 +94,7 @@ launch_background_command() {
 
 cleanup_background_jobs() {
   local pid=""
-  for pid in "${background_pids[@]}"; do
+  for pid in "${background_pids[@]:+${background_pids[@]}}"; do
     if kill -0 "$pid" >/dev/null 2>&1; then
       terminate_pid_tree "$pid"
     else
@@ -126,7 +126,7 @@ on_exit() {
   cleanup_virtualenv
 
   if [[ ${#failed_pids[@]} -gt 0 ]]; then
-    echo "The following background processes exited with nonzero status: ${failed_pids[@]}"
+    echo "The following background processes exited with nonzero status: ${failed_pids[@]:+${failed_pids[@]}}"
     return 1
   fi
   return 0

From 4d908f2e2f6dd4931eae9847ed6d6aacaa98d452 Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 20:58:00 +0100
Subject: [PATCH 4/7] bash: avoid waiting on taskkilled jobs

---
 test-wheel.bash | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index d7a60e2..b519764 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -52,18 +52,15 @@ terminate_pid_tree() {
 
   if [[ "$is_windows_shell" == true ]] && command -v taskkill >/dev/null 2>&1; then
     taskkill //PID "$pid" //T //F >/dev/null 2>&1 || true
-  else
-    kill -TERM "-$pid" >/dev/null 2>&1 || kill "$pid" >/dev/null 2>&1 || true
+    return 0
   fi
 
+  kill -TERM "-$pid" >/dev/null 2>&1 || kill "$pid" >/dev/null 2>&1 || true
+
   local deadline=$((SECONDS + 20))
   while kill -0 "$pid" >/dev/null 2>&1; do
     if (( SECONDS >= deadline )); then
-      if [[ "$is_windows_shell" == true ]] && command -v taskkill >/dev/null 2>&1; then
-        taskkill //PID "$pid" //T //F >/dev/null 2>&1 || true
-      else
-        kill -KILL "-$pid" >/dev/null 2>&1 || kill -9 "$pid" >/dev/null 2>&1 || true
-      fi
+      kill -KILL "-$pid" >/dev/null 2>&1 || kill -9 "$pid" >/dev/null 2>&1 || true
       break
     fi
     sleep 1
@@ -95,6 +92,15 @@ launch_background_command() {
 cleanup_background_jobs() {
   local pid=""
   for pid in "${background_pids[@]:+${background_pids[@]}}"; do
+    if [[ "$is_windows_shell" == true ]]; then
+      if kill -0 "$pid" >/dev/null 2>&1; then
+        terminate_pid_tree "$pid"
+      else
+        wait "$pid" 2>/dev/null || true
+      fi
+      continue
+    fi
+
     if kill -0 "$pid" >/dev/null 2>&1; then
       terminate_pid_tree "$pid"
     else

From f1a038cbd4044f0b24019ee2493d00d09ae010af Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 22:01:45 +0100
Subject: [PATCH 5/7] bash: skip blocking venv cleanup on windows

---
 test-wheel.bash | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index b519764..5063a5e 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -116,10 +116,21 @@ cleanup_background_jobs() {
 }
 
 cleanup_virtualenv() {
-  if [[ "$cleanup" == "true" ]]; then
-    echo "→ Removing $venv"
-    rm -rf "$venv"
+  if [[ "$cleanup" != "true" ]]; then
+    return 0
+  fi
+
+  if [[ "$is_windows_shell" == true ]]; then
+    # GitHub's Windows runners clean the workspace after each job anyway.
+    # Avoid synchronously deleting the temporary venv here: Git-Bash/MSYS can
+    # spend minutes tearing down a Python tree after the background services
+    # were killed, which turns integration tests into apparent hangs.
+    echo "→ Skipping synchronous removal of $venv on Windows"
+    return 0
   fi
+
+  echo "→ Removing $venv"
+  rm -rf "$venv"
 }
 
 on_exit() {

From 03b832b35ca84958365b33fb366a0d4e7f09c9e7 Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 22:26:18 +0100
Subject: [PATCH 6/7] bash: use shell pids for windows cleanup

---
 test-wheel.bash | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index 5063a5e..24fd7c9 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -50,8 +50,22 @@ terminate_pid_tree() {
     return 0
   fi
 
-  if [[ "$is_windows_shell" == true ]] && command -v taskkill >/dev/null 2>&1; then
-    taskkill //PID "$pid" //T //F >/dev/null 2>&1 || true
+  if [[ "$is_windows_shell" == true ]]; then
+    # Git-Bash/MSYS background jobs are tracked via shell PIDs. Use POSIX
+    # signals against that PID namespace instead of `taskkill`, which expects
+    # native Windows PIDs and can silently miss the spawned service.
+    kill -TERM "$pid" >/dev/null 2>&1 || true
+
+    local deadline=$((SECONDS + 20))
+    while kill -0 "$pid" >/dev/null 2>&1; do
+      if (( SECONDS >= deadline )); then
+        kill -KILL "$pid" >/dev/null 2>&1 || true
+        break
+      fi
+      sleep 1
+    done
+
+    wait "$pid" 2>/dev/null || true
     return 0
   fi
 
@@ -92,15 +106,6 @@ launch_background_command() {
 cleanup_background_jobs() {
   local pid=""
   for pid in "${background_pids[@]:+${background_pids[@]}}"; do
-    if [[ "$is_windows_shell" == true ]]; then
-      if kill -0 "$pid" >/dev/null 2>&1; then
-        terminate_pid_tree "$pid"
-      else
-        wait "$pid" 2>/dev/null || true
-      fi
-      continue
-    fi
-
     if kill -0 "$pid" >/dev/null 2>&1; then
       terminate_pid_tree "$pid"
     else

From b9f7254585fc9e7c937e5240c68caabde127698d Mon Sep 17 00:00:00 2001
From: Joseph Birkner <j.birkner@klebert-engineering.de>
Date: Tue, 24 Mar 2026 22:39:06 +0100
Subject: [PATCH 7/7] bash: keep windows cleanup non-blocking

---
 test-wheel.bash | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/test-wheel.bash b/test-wheel.bash
index 24fd7c9..593b55a 100755
--- a/test-wheel.bash
+++ b/test-wheel.bash
@@ -54,18 +54,11 @@ terminate_pid_tree() {
     # Git-Bash/MSYS background jobs are tracked via shell PIDs. Use POSIX
     # signals against that PID namespace instead of `taskkill`, which expects
     # native Windows PIDs and can silently miss the spawned service.
+    #
+    # Keep this non-blocking on Windows: waiting/spinning in the MSYS shell can
+    # itself fail with `fork: Resource temporarily unavailable` during test
+    # teardown.
     kill -TERM "$pid" >/dev/null 2>&1 || true
-
-    local deadline=$((SECONDS + 20))
-    while kill -0 "$pid" >/dev/null 2>&1; do
-      if (( SECONDS >= deadline )); then
-        kill -KILL "$pid" >/dev/null 2>&1 || true
-        break
-      fi
-      sleep 1
-    done
-
-    wait "$pid" 2>/dev/null || true
     return 0
   fi
 
@@ -106,6 +99,15 @@ launch_background_command() {
 cleanup_background_jobs() {
   local pid=""
   for pid in "${background_pids[@]:+${background_pids[@]}}"; do
+    if [[ "$is_windows_shell" == true ]]; then
+      if kill -0 "$pid" >/dev/null 2>&1; then
+        terminate_pid_tree "$pid"
+      else
+        wait "$pid" 2>/dev/null || true
+      fi
+      continue
+    fi
+
     if kill -0 "$pid" >/dev/null 2>&1; then
       terminate_pid_tree "$pid"
     else