fix(ci): improve trap handling in regression and test scripts

Refactor trap usage in .github/regression.sh to use a variable for the error
trap string, ensuring proper quoting and shellcheck compliance. Enhance
cleanup logic to ignore further interrupts and errors during cleanup, and
disable unnecessary traps after tests finish.

In .github/run_tests.sh, add --foreground to the timeout command to ensure
proper signal handling when running pytest with a session timeout.

Author: mkoura

.github/regression.sh

@@ -2,7 +2,11 @@
 # shellcheck shell=bash disable=SC2317
 
 set -Eeuo pipefail
-trap 'echo "Error at line $LINENO"' ERR
+
+# shellcheck disable=SC2016
+basic_err_string='echo "Error at line $LINENO"'
+# shellcheck disable=SC2064
+trap "$basic_err_string" ERR
 
 nix --version
 df -h .
@@ -188,6 +192,12 @@ _cleanup_testnet_on_interrupt() {
 # cleanup on Ctrl+C or error
 # shellcheck disable=SC2329
 _interrupted() {
+  # Ignore further interrupts and errors during cleanup
+  trap '' SIGINT
+  # shellcheck disable=SC2064
+  trap "$basic_err_string" ERR
+  set +e
+
   # Do testnet cleanup only on interrupted testrun. When not interrupted,
   # cleanup is done as part of a testrun.
   _cleanup_testnet_on_interrupt || :
@@ -238,7 +248,7 @@ MON_PID=$!
 
 # ensure cleanup on ANY exit (success, error, Ctrl-C, set -e, etc.)
 # shellcheck disable=SC2064
-trap "echo 'Stopping monitor'; kill $MON_PID 2>/dev/null || true" EXIT
+trap "echo 'Stopping monitor'; kill ${MON_PID:-} 2>/dev/null || true" EXIT
 
 # Run tests and generate report
 
@@ -283,7 +293,13 @@ if [ "${KEEP_CLUSTERS_RUNNING:-""}" = 1 ]; then
   read -r
 fi
 
+# redefine the ERR trap to avoid interfering with cleanup
+# shellcheck disable=SC2064
+trap "$basic_err_string" ERR
+# ignore Ctrl+C during cleanup
+trap '' SIGINT
 _cleanup
+trap - SIGINT
 
 # prepare artifacts for upload in GitHub Actions
 if [ -n "${GITHUB_ACTIONS:-""}" ]; then

.github/run_tests.sh

@@ -54,7 +54,7 @@ EOF
 
 run_pytest() {
   if [ -n "${SESSION_TIMEOUT:-}" ]; then
-    local -a timeout_arr=( "--signal=INT" "--kill-after=0" "$SESSION_TIMEOUT" )
+    local -a timeout_arr=( "--foreground" "--signal=INT" "--kill-after=0" "$SESSION_TIMEOUT" )
     echo "Running: PYTEST_ADDOPTS='${PYTEST_ADDOPTS:-}' timeout ${timeout_arr[*]} pytest $*"
     timeout "${timeout_arr[@]}" pytest "$@"
   else