Fix the v0.7.4 Linux release build: GTK hook with X11 commented out

scripts/fix-appimage-wayland.sh

@@ -36,6 +36,11 @@
 # next real resize. The hook is rewritten to prefer Wayland and fall back to
 # X11, and to let a GDK_BACKEND the user has already exported win.
 #
+# Tauri's CLI now ships its own copy of the plugin (tauri-apps/tauri#16062),
+# whose hook carries the line commented out — `# export GDK_BACKEND=x11`. Only
+# an active export forces X11, so only that is rewritten; a hook that leaves
+# GDK_BACKEND unset already gets GTK's own Wayland-then-X11 choice.
+#
 # Usage:
 #   scripts/fix-appimage-wayland.sh <AppImage> [more...]   strip and repack
 #   scripts/fix-appimage-wayland.sh --strip-only <AppDir>  strip in place
@@ -54,9 +59,10 @@ STRIP_LIBS=(
   libwayland-server.so.0
 )
 
-# The hook the GTK plugin writes, and the line in it that forces X11.
+# The hook the GTK plugin writes, and the line in it that forces X11: an
+# active export, not the same text inside a comment.
 GTK_HOOK=apprun-hooks/linuxdeploy-plugin-gtk.sh
-GDK_FORCED_X11='export GDK_BACKEND=x11'
+GDK_FORCED_X11='^[[:space:]]*export[[:space:]]+GDK_BACKEND=x11([[:space:]]|$)'
 GDK_PREFER_WAYLAND='export GDK_BACKEND="${GDK_BACKEND:-wayland,x11}" # rewritten by fix-appimage-wayland.sh: native Wayland where it exists, X11 otherwise, and an exported value wins'
 
 info() { printf '\033[1;34m==>\033[0m %s\n' "$*"; }
@@ -85,11 +91,11 @@ strip_appdir() {
 prefer_wayland() {
   local hook="$1/$GTK_HOOK"
   [[ -f "$hook" ]] || { printf '0'; return 0; }
-  if grep -qF "$GDK_FORCED_X11" "$hook"; then
-    # Whole-line replacement on the exact export, via awk rather than sed so
-    # the replacement's $ and " need no escaping.
+  if grep -qE "$GDK_FORCED_X11" "$hook"; then
+    # Whole-line replacement of the export, via awk rather than sed so the
+    # replacement's $ and " need no escaping.
     awk -v from="$GDK_FORCED_X11" -v to="$GDK_PREFER_WAYLAND" \
-      'index($0, from) == 1 { print to; next } { print }' "$hook" > "$hook.tmp" \
+      '$0 ~ from { print to; next } { print }' "$hook" > "$hook.tmp" \
       && mv "$hook.tmp" "$hook"
     printf '    rewrote %s\n' "$GTK_HOOK" >&2
     printf '1'
@@ -181,7 +187,7 @@ for IMG in "$@"; do
   find "$VERIFY/squashfs-root" -name 'libwebkit2gtk-4.1.so.0' | grep -q . \
     || die "libwebkit2gtk missing from the repacked AppImage — bad repack."
   if [[ -f "$VERIFY/squashfs-root/$GTK_HOOK" ]]; then
-    grep -qF "$GDK_FORCED_X11" "$VERIFY/squashfs-root/$GTK_HOOK" \
+    grep -qE "$GDK_FORCED_X11" "$VERIFY/squashfs-root/$GTK_HOOK" \
       && die "the GTK hook still forces GDK_BACKEND=x11 after the repack."
   fi
 

scripts/test-fix-appimage-wayland.sh

@@ -14,6 +14,8 @@
 #   * both AppDir layouts are handled (usr/lib and usr/lib/<triplet>)
 #   * the GTK plugin's hook stops forcing GDK_BACKEND=x11, prefers Wayland,
 #     and still lets a user's own exported GDK_BACKEND win
+#   * a hook that only mentions the export in a comment (Tauri's bundled
+#     plugin) is left alone, and an indented export is still caught
 #   * a second run is a clean no-op rather than an error
 #   * a missing AppDir fails loudly instead of silently succeeding
 #
@@ -138,6 +140,52 @@ else
   fail "the rewrite disturbed lines other than the GDK_BACKEND export"
 fi
 
+# ---------------------------------------------------------------- case 2c ---
+# Tauri's CLI ships its own copy of the plugin, and its hook has the line
+# commented out. That forces nothing: the hook must come through byte for
+# byte, and GDK_BACKEND stays unset for GTK to choose. Matching the text
+# inside the comment is what failed the v0.7.4 Linux release build.
+C="$T/Commented"
+mkdir -p "$C/apprun-hooks"
+cat > "$C/apprun-hooks/linuxdeploy-plugin-gtk.sh" <<'HOOK'
+#! /usr/bin/env bash
+export GTK_THEME="$APPIMAGE_GTK_THEME" # Custom themes are broken
+# export GDK_BACKEND=x11 # Monitor this closely. AppImage used to crash on Wayland!
+export XDG_DATA_DIRS="$APPDIR/usr/share:/usr/share:$XDG_DATA_DIRS" # g_get_system_data_dirs() from GLib
+HOOK
+cp "$C/apprun-hooks/linuxdeploy-plugin-gtk.sh" "$T/commented-before.sh"
+out=$(bash "$SCRIPT" --strip-only "$C" 2>&1) || fail "strip-only exited non-zero on a commented hook"
+if [[ "$out" == *"hook rewritten: 0"* ]] \
+   && cmp -s "$T/commented-before.sh" "$C/apprun-hooks/linuxdeploy-plugin-gtk.sh"; then
+  pass "a commented-out export is left alone"
+else
+  fail "a hook whose export is only a comment was changed ($out)"
+fi
+got=$(backend_after "$C/apprun-hooks/linuxdeploy-plugin-gtk.sh")
+if [[ -z "$got" ]]; then
+  pass "the commented hook leaves GDK_BACKEND for GTK to choose"
+else
+  fail "expected GDK_BACKEND unset after the commented hook, got '$got'"
+fi
+
+# An active export does not have to start in column one — inside an `if` it
+# is indented, and it forces X11 all the same.
+I="$T/Indented"
+mkdir -p "$I/apprun-hooks"
+cat > "$I/apprun-hooks/linuxdeploy-plugin-gtk.sh" <<'HOOK'
+#! /usr/bin/env bash
+if true; then
+    export GDK_BACKEND=x11
+fi
+HOOK
+bash "$SCRIPT" --strip-only "$I" >/dev/null 2>&1 || fail "strip-only exited non-zero on an indented hook"
+got=$(backend_after "$I/apprun-hooks/linuxdeploy-plugin-gtk.sh")
+if [[ "$got" == "wayland,x11" ]]; then
+  pass "an indented export is rewritten too"
+else
+  fail "expected GDK_BACKEND=wayland,x11 after an indented export, got '$got'"
+fi
+
 # ---------------------------------------------------------------- case 3 ----
 # Idempotency: re-running over an already-clean AppDir must succeed quietly,
 # because the release workflow may be re-run against the same artefacts.