Add regression tests for run_vulkan launcher path resolution

CMakeLists.txt

@@ -2073,4 +2073,9 @@ if(BUILD_UNIT_TESTS)
 	target_include_directories(unit_macros PRIVATE ${CMAKE_SOURCE_DIR}/src)
 	add_test(NAME unit_macros COMMAND unit_macros)
 	set_tests_properties(unit_macros PROPERTIES LABELS "unit;validation")
+
+	add_test(NAME unit_run_vulkan_script
+		COMMAND /usr/bin/env bash ${CMAKE_SOURCE_DIR}/tests/scripts/test_run_vulkan.sh ${CMAKE_SOURCE_DIR}/scripts/run_vulkan.sh
+		WORKING_DIRECTORY ${CMAKE_SOURCE_DIR})
+	set_tests_properties(unit_run_vulkan_script PROPERTIES LABELS "unit;validation")
 endif()

tests/scripts/test_run_vulkan.sh

@@ -0,0 +1,171 @@
+#!/usr/bin/env bash
+# Unit test for scripts/run_vulkan.sh launcher behavior.
+set -euo pipefail
+
+SCRIPT_UNDER_TEST="${1:-}"
+if [ -z "$SCRIPT_UNDER_TEST" ]; then
+	SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+	SCRIPT_UNDER_TEST="$(cd "$SCRIPT_DIR/../.." && pwd)/scripts/run_vulkan.sh"
+fi
+
+if [ ! -f "$SCRIPT_UNDER_TEST" ]; then
+	echo "FAIL: run_vulkan.sh not found at '$SCRIPT_UNDER_TEST'" >&2
+	exit 1
+fi
+
+TMP_ROOT="$(mktemp -d)"
+cleanup() {
+	rm -rf "$TMP_ROOT"
+}
+trap cleanup EXIT
+
+assert_contains() {
+	local haystack="$1"
+	local needle="$2"
+	local message="$3"
+	if [[ "$haystack" != *"$needle"* ]]; then
+		echo "FAIL: $message" >&2
+		echo "Expected to find: $needle" >&2
+		echo "Actual output:" >&2
+		printf '%s\n' "$haystack" >&2
+		exit 1
+	fi
+}
+
+make_fake_uname() {
+	local bin_dir="$1"
+	local arch="$2"
+
+	mkdir -p "$bin_dir"
+	cat > "$bin_dir/uname" <<EOF
+#!/usr/bin/env bash
+echo "$arch"
+EOF
+	chmod +x "$bin_dir/uname"
+}
+
+make_fake_engine() {
+	local path="$1"
+
+	mkdir -p "$(dirname "$path")"
+	cat > "$path" <<'EOF'
+#!/usr/bin/env bash
+echo "ENGINE:$0"
+echo "ARGS:$*"
+echo "LDLP:${LD_LIBRARY_PATH:-}"
+EOF
+	chmod +x "$path"
+}
+
+copy_script() {
+	local target_path="$1"
+	mkdir -p "$(dirname "$target_path")"
+	cp "$SCRIPT_UNDER_TEST" "$target_path"
+	chmod +x "$target_path"
+}
+
+test_repo_layout_uses_release_dir() {
+	local root="$TMP_ROOT/repo_release"
+	local script_path="$root/scripts/run_vulkan.sh"
+	local mock_bin="$root/mockbin"
+	local home_dir="$root/home"
+	local output
+
+	copy_script "$script_path"
+	make_fake_engine "$root/release/idtech3"
+	make_fake_uname "$mock_bin" "x86_64"
+	mkdir -p "$home_dir"
+
+	output="$(PATH="$mock_bin:$PATH" HOME="$home_dir" "$script_path" +set cl_renderer vulkan)"
+
+	assert_contains "$output" "ENGINE:$root/release/idtech3" "script should launch release/idtech3 when run from scripts/"
+	assert_contains "$output" "ARGS:+set cl_renderer vulkan" "script should preserve arguments"
+}
+
+test_arch_specific_binary_is_preferred() {
+	local root="$TMP_ROOT/arch_specific"
+	local script_path="$root/scripts/run_vulkan.sh"
+	local mock_bin="$root/mockbin"
+	local home_dir="$root/home"
+	local output
+
+	copy_script "$script_path"
+	make_fake_engine "$root/release/idtech3"
+	make_fake_engine "$root/release/idtech3.aarch64"
+	make_fake_uname "$mock_bin" "aarch64"
+	mkdir -p "$home_dir"
+
+	output="$(PATH="$mock_bin:$PATH" HOME="$home_dir" "$script_path")"
+
+	assert_contains "$output" "ENGINE:$root/release/idtech3.aarch64" "aarch64 should prefer idtech3.aarch64 when executable exists"
+}
+
+test_arch_specific_fallback_to_generic_binary() {
+	local root="$TMP_ROOT/arch_fallback"
+	local script_path="$root/scripts/run_vulkan.sh"
+	local mock_bin="$root/mockbin"
+	local home_dir="$root/home"
+	local output
+
+	copy_script "$script_path"
+	make_fake_engine "$root/release/idtech3"
+	mkdir -p "$root/release"
+	printf '#!/usr/bin/env bash\nexit 0\n' > "$root/release/idtech3.aarch64"
+	chmod 0644 "$root/release/idtech3.aarch64"
+	make_fake_uname "$mock_bin" "aarch64"
+	mkdir -p "$home_dir"
+
+	output="$(PATH="$mock_bin:$PATH" HOME="$home_dir" "$script_path")"
+
+	assert_contains "$output" "ENGINE:$root/release/idtech3" "aarch64 should fall back to idtech3 when idtech3.aarch64 is not executable"
+}
+
+test_non_repo_layout_falls_back_to_script_dir() {
+	local root="$TMP_ROOT/script_dir_fallback"
+	local script_path="$root/bin/run_vulkan.sh"
+	local mock_bin="$root/mockbin"
+	local home_dir="$root/home"
+	local output
+
+	copy_script "$script_path"
+	make_fake_engine "$root/bin/idtech3"
+	make_fake_uname "$mock_bin" "x86_64"
+	mkdir -p "$home_dir"
+
+	output="$(PATH="$mock_bin:$PATH" HOME="$home_dir" "$script_path")"
+
+	assert_contains "$output" "ENGINE:$root/bin/idtech3" "script should fall back to its own directory if ../release is unavailable"
+}
+
+test_ld_library_path_prepend_behavior() {
+	local root="$TMP_ROOT/ld_library_path"
+	local script_path="$root/scripts/run_vulkan.sh"
+	local mock_bin="$root/mockbin"
+	local home_dir="$root/home"
+	local output
+	local expected_ldlp
+
+	copy_script "$script_path"
+	make_fake_engine "$root/release/idtech3"
+	make_fake_uname "$mock_bin" "x86_64"
+	mkdir -p "$home_dir/sdl2-vulkan-install/lib"
+	touch "$home_dir/sdl2-vulkan-install/lib/libSDL2.so"
+
+	output="$(PATH="$mock_bin:$PATH" HOME="$home_dir" LD_LIBRARY_PATH="/opt/custom" "$script_path")"
+
+	if [ -f "/usr/local/lib/libSDL2.so" ] || [ -f "/usr/local/lib/aarch64-linux-gnu/libSDL2.so" ]; then
+		expected_ldlp="/usr/local/lib:/opt/custom"
+	else
+		expected_ldlp="$home_dir/sdl2-vulkan-install/lib:/opt/custom"
+	fi
+
+	assert_contains "$output" "LDLP:$expected_ldlp" "script should prepend selected SDL path and preserve LD_LIBRARY_PATH"
+}
+
+test_repo_layout_uses_release_dir
+test_arch_specific_binary_is_preferred
+test_arch_specific_fallback_to_generic_binary
+test_non_repo_layout_falls_back_to_script_dir
+test_ld_library_path_prepend_behavior
+
+echo "PASS: unit_run_vulkan_script"