From 94e8a8e3a3f4473f64205f5ed343df4708c686fa Mon Sep 17 00:00:00 2001
From: pvincent <pvincent@artcode.re>
Date: Sun, 26 Jul 2026 12:20:39 +0400
Subject: [PATCH] poc miaou_debug

---
 poc                     | 51 +++++++++++++++++++++++++++++------------
 test/stub/scenario.bash |  6 +++--
 2 files changed, 40 insertions(+), 17 deletions(-)

diff --git a/poc b/poc
index 68d262e..b9f7144 100755
--- a/poc
+++ b/poc
@@ -2,11 +2,23 @@
 
 # constants
 
+MIAOU_BASH_ERROR=$(mktemp -t "$(basename "$0").XXXXXXXX" --tmpdir="/run/user/$(id -u)")
+MIAOU_DEBUG=${MIAOU_DEBUG:-false}
+readonly MIAOU_BASH_ERROR MIAOU_DEBUG
+
 ## functions
 
+function is_true {
+  [[ "${1:-}" == 'true' ]]
+}
+
+function miaou_debug {
+  is_true "${MIAOU_DEBUG}" && >/dev/tty builtin echo -e "\e[90mDEBUG <==> \e[95m$*\e[0m" || true
+}
+
 function on_error {
-  code="${1:-0}"
-  >&2 echo on_error: $$ $BASHPID
+  code="${1:-100}"
+  miaou_debug on_error: $$ $BASHPID
   if [[ $$ == "$BASHPID" ]]; then
     >&2 echo "${BASH_SOURCE[1]}: line ${BASH_LINENO[0]}: command_error: ${code}"
     exit "$code"
@@ -14,35 +26,44 @@ function on_error {
     >&2 echo "${BASH_SOURCE[1]}: line ${BASH_LINENO[0]}: subshell_error: ${code}"
     kill -PIPE $$
   fi
-  # kill -INT $BASHPID
-  # kill -INT $$
 }
 
 function on_exit {
   code="${1:-0}"
-  echo "on_exit $code"
+
+  miaou_debug --stderr--
+  mapfile -t tmp_error <"$MIAOU_BASH_ERROR"
+  for i in "${tmp_error[@]}"; do >&4 echo -e "$i"; done
+  last_error="${tmp_error[-1]}"
+  miaou_debug --end of stderr--
+
+  miaou_debug "on_exit $code"
 }
 
 function on_pipe {
-  >&2 echo on_pipe: $$ $BASHPID
-  #TODO: compute code from latest sterr in case of command_error
-  code="${1:-24}" # 24 => CTRL-C
+  local code=141 # default code error for pipe
+  local tmp_error regex
 
-  trap - EXIT ERR PIPE
+  mapfile -t tmp_error <"$MIAOU_BASH_ERROR"
+  last_error="${tmp_error[-1]}"
+  regex='.*: line [0-9]+: subshell_error: ([0-9]+)'
+  [[ $last_error =~ $regex ]] && code=${BASH_REMATCH[1]}
+
+  miaou_debug on_pipe: "${code}"
   exit "$code"
 }
 
 ## main
 
 set -euo pipefail
-set -T # DEBUG RETURN
-set -E # ERR on subshell
-# set -b
+set -E # HALT on subshell error
+# set -T # DEBUG RETURN
 
 trap 'on_error $?' ERR
 trap 'on_exit $?' EXIT
 trap 'on_pipe' PIPE
 
-echo "${BASHPID}"
-
-source ./test/stub/scenario.bash subshell_term
+echo "--SOURCE scenario ${BASHPID}"
+exec 3> >(tee "$MIAOU_BASH_ERROR" >/dev/null) 4>/dev/stderr
+source ./test/stub/scenario.bash subshell_term 2>&3
+echo "--SUCCESS scenario"
diff --git a/test/stub/scenario.bash b/test/stub/scenario.bash
index 0da564a..01f132b 100755
--- a/test/stub/scenario.bash
+++ b/test/stub/scenario.bash
@@ -14,9 +14,11 @@ function do_subshell_false {
 
 function do_subshell_term {
 
-  # grep none none
+  echo toto
+  # echo 'toto' | grep none
 
-  echo "found1=$(grep nope nope)"
+  echo -n "found1=$(grep nope nope)"
+  echo "found1=$(grep nope nope | grep none)"
   echo "found2=$(command_not_found)"
   echo SHOULD NOT SHOW UP!
 }