[Tarantool-patches] [PATCH v2 luajit 3/6] test: introduce utils.h helper for C tests

[Sergey Kaplun via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

This header contains generic init and close for tests and helpers for
loading auxiliary Lua script with functions to run inside a C test.

It will be properly used in the next commit.

Part of tarantool/tarantool#7900
---
 test/tarantool-c-tests/utils.h | 63 ++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)
 create mode 100644 test/tarantool-c-tests/utils.h

diff --git a/test/tarantool-c-tests/utils.h b/test/tarantool-c-tests/utils.h
new file mode 100644
index 00000000..cf668006
--- /dev/null
+++ b/test/tarantool-c-tests/utils.h
@@ -0,0 +1,63 @@
+#include <limits.h>
+#include <string.h>
+
+#include "lauxlib.h"
+#include "lua.h"
+#include "luajit.h"
+#include "lualib.h"
+
+#include "test.h"
+
+/* Generic init for our tests. */
+static lua_State *utils_lua_init(void)
+{
+	lua_State *L = luaL_newstate();
+	if (!L)
+		bail_out("Can't init Lua state");
+	/* Stop collector during library initialization. */
+	lua_gc(L, LUA_GCSTOP, 0);
+	luaL_openlibs(L);
+	lua_gc(L, LUA_GCRESTART, -1);
+	return L;
+}
+
+/* Generic close for our tests. */
+static void utils_lua_close(lua_State *L)
+{
+	lua_close(L);
+}
+
+/*
+ * Load the pair to the test file <filename-script.lua>.
+ * Each file should return the table with functions (named the
+ * same as the corresponding unit tests) to call in unit tests.
+ * Push the table with those functions on the Lua stack.
+ */
+#define utils_load_aux_script(L) do {					\
+	/* 								\
+	 * Format script name. 						\
+	 * `__ABS_FILENAME__` is set via CMake.				\
+	 */								\
+	char script[PATH_MAX] = __ABS_FILENAME__;			\
+	char *file_suffix = strstr(script, ".test.c");			\
+	strcpy(file_suffix, "-script.lua");				\
+									\
+	if (luaL_dofile((L), script) != LUA_OK) {			\
+		test_comment("Can't load %s: '%s'", script,		\
+			     lua_tostring((L), -1));			\
+		bail_out("Can't load auxiliary script");		\
+	}								\
+									\
+	if (!lua_istable((L), -1))					\
+		bail_out("Returned value from script is not a table");	\
+} while (0)
+
+/*
+ * Accept a table on top of the Lua stack which containing the
+ * function named as the unit test we currently executing.
+ */
+#define utils_get_aux_lfunc(L) do {					\
+	lua_getfield((L), -1, __func__);				\
+	if (!lua_isfunction((L), -1))					\
+		bail_out("Can't get auxiliary test function");		\
+} while (0)
-- 
2.34.1