build: Add thorough test setup

This allows the tests to be run with `meson test --setup thorough` and
it will run all the GTest tests with `-m thorough`.

Since this argument isn’t supported by the Python tests, it’s not passed
to them.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>

.gitlab-ci/thorough-test-wrapper.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+#
+# Copyright 2024 GNOME Foundation, Inc.
+#
+# SPDX-License-Identifier: LGPL-2.1-or-later
+#
+# Original author: Philip Withnall
+
+set -e
+
+# If the test is run under Python (e.g. the first argument to this script is
+# /usr/bin/python3) or if it’s the special xmllint test in GLib, then don’t
+# pass the GTest `-m thorough` argument to it.
+if [[ "$1" == *"python"* ||
+      "$1" == *"xmllint" ]]; then
+  args=()
+else
+  # See the documentation for g_test_init()
+  args=("-m" "thorough")
+fi
+
+exec "$@" "${args[@]}"