fix: tools/bugreport launcher finds a Python 3.8+ itself and never starts a Store alias (#166)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SnAJ7Z3CpVD3PRbN73QtU2

Files changed:
- .gitea/workflows/ci.yml
- CHANGES.md
- INSTALL.md
- VERSION
- instructions/bug-report.md
- tools/README.md
- tools/bugreport
- tools/bugreport.ps1
- tools/bugreport.py
- tools/chemenu/tests/test_bugreport_launcher.py
- tools/chemenu/tests/test_instructions_shell.py
- tools/chemenu/tests/test_portability.py

tools/bugreport

@@ -0,0 +1,129 @@
+#!/bin/sh
+# Entry point for the bug-report collector, so agents and people start it through one
+# stable path on every platform:
+#
+#   tools/bugreport [options]
+#
+# This is the POSIX half - Linux, macOS and Git Bash on Windows. PowerShell resolves
+# the same string to tools/bugreport.ps1 first.
+#
+# tools/bugreport.py is the one part of the stack that has to run when nothing else
+# does, so this script assumes nothing the preflight sets up: no .wikitool-tools.json,
+# no venv. It looks for a Python itself, the way the preflight does - on Windows
+# python, py -3, python3; elsewhere python3, python; every match on PATH in PATH
+# order - and only then tries the venv's. It never starts anything under WindowsApps:
+# there, python.exe and python3.exe are the Microsoft Store's aliases, and in Git Bash
+# `python3` is exactly that. Every candidate is probed first, so one that is too old or
+# that the machine refuses to run (a venv python.exe blocked by Defender) is passed over
+# rather than ending the report.
+#
+# Without any Python 3.8 or newer it says so and exits 1, never 42: the collector opens
+# no gate.
+#
+# CHEMENU_PREFLIGHT_PLATFORM stands in for the platform, as it does for the preflight;
+# the test suite is its only user.
+set -u
+DIR=$(CDPATH='' cd -- "$(dirname -- "$0")" && pwd -P) || exit 1
+MIN=3.8
+# Exit 3 marks "a Python, but too old" apart from "did not start at all".
+PROBE='import sys; sys.exit(0 if sys.version_info >= (3, 8) else 3)'
+
+platform=${CHEMENU_PREFLIGHT_PLATFORM:-}
+if [ -z "$platform" ]; then
+    case "$(uname -s 2>/dev/null)" in
+        MINGW*|MSYS*|CYGWIN*) platform=windows ;;
+        *) platform=other ;;
+    esac
+fi
+
+if [ "$platform" = windows ]; then
+    order="python: py:-3 python3:"
+    looked="python, py -3, python3"
+else
+    order="python3: python:"
+    looked="python3, python"
+fi
+
+is_store_alias() {
+    case "$1" in *[Ww]indows[Aa]pps/*|*[Ww]indows[Aa]pps\\*) return 0 ;; esac
+    return 1
+}
+
+# Every executable called <name> on PATH, in PATH order, store aliases dropped.
+on_path() {
+    set -f
+    old_ifs=$IFS
+    IFS=:
+    for d in $PATH; do
+        [ -n "$d" ] || d=.
+        for f in "$d/$1" "$d/$1.exe"; do
+            if [ -f "$f" ] && [ -x "$f" ] && ! is_store_alias "$f"; then
+                printf '%s\n' "$f"
+            fi
+        done
+    done
+    IFS=$old_ifs
+    set +f
+}
+
+PY="" EXTRA="" TOO_OLD=""
+
+probe() { # <path> [extra argument, e.g. -3 for py] -> sets PY/EXTRA on success
+    "$@" -c "$PROBE" >/dev/null 2>&1
+    status=$?
+    if [ "$status" -eq 0 ]; then
+        PY=$1 EXTRA=${2:-}
+        return 0
+    fi
+    if [ "$status" -eq 3 ]; then
+        TOO_OLD="$TOO_OLD
+  $1"
+    fi
+    return 1
+}
+
+for candidate in $order; do
+    name=${candidate%%:*}
+    extra=${candidate#*:}
+    found=$(on_path "$name")
+    [ -n "$found" ] || continue
+    # A here-document, not a pipe: `break 2` has to leave the outer loop of this
+    # shell, and a path may contain spaces ("Program Files").
+    while IFS= read -r path; do
+        if [ -n "$extra" ]; then
+            probe "$path" "$extra" && break 2
+        else
+            probe "$path" && break 2
+        fi
+    done <<EOF
+$found
+EOF
+done
+
+if [ -z "$PY" ]; then
+    for venv in "$DIR/.venv/bin/python" "$DIR/.venv/Scripts/python.exe"; do
+        [ -f "$venv" ] && probe "$venv" && break
+    done
+fi
+
+if [ -n "$PY" ]; then
+    if [ -n "$EXTRA" ]; then
+        exec "$PY" "$EXTRA" "$DIR/bugreport.py" "$@"
+    fi
+    exec "$PY" "$DIR/bugreport.py" "$@"
+fi
+
+{
+    echo "No Python $MIN or newer could be started, so the bug-report collector did not run."
+    echo "Looked for $looked on PATH, then the one in tools/.venv. Microsoft Store aliases"
+    echo "under WindowsApps are skipped on purpose - they do not run Python."
+    if [ -n "$TOO_OLD" ]; then
+        echo "Found, but older than $MIN:$TOO_OLD"
+    fi
+    echo
+    echo "Install Python $MIN or newer, or start the collector directly with the full path"
+    echo "of one that works:"
+    echo
+    echo "  <full path to python> tools/bugreport.py <the same options>"
+} >&2
+exit 1