Merge pull request #3951 from Kelimion/lua_test

Add Lua example to `vendor:lua` as well as basic tests.

tests/vendor/all.odin

@@ -1,3 +1,4 @@
 package tests_vendor
 
 @(require) import "glfw"
+@(require) import "lua/5.4"

tests/vendor/lua/5.4/factorial.lua

@@ -0,0 +1,10 @@
+-- defines a factorial function
+function fact (n)
+  if n == 0 then
+    return 1
+  else
+    return n * fact(n-1)
+  end
+end
+    
+return fact(10)

tests/vendor/lua/5.4/test_vendor_lua.5.4.odin

@@ -0,0 +1,71 @@
+//+build windows, linux, darwin
+package test_vendor_lua_54
+
+import "core:testing"
+import "core:c"
+import lua "vendor:lua/5.4"
+import "base:runtime"
+
+@(test)
+// Test context.allocator and returning a string
+return_string_with_context_based_allocator :: proc(t: ^testing.T) {
+	_context := context
+
+	state: ^lua.State
+	state = lua.newstate(lua_context_allocator, &_context)
+	defer lua.close(state)
+
+	lua.L_dostring(state, "return 'somestring'")
+	str := lua.tostring(state, -1)
+
+	testing.expectf(
+		t, str == "somestring", "Expected Lua to return \"somestring\"",
+	)
+}
+
+@(test)
+// Test lua.dofile and returning an integer
+dofile_factorial :: proc(t: ^testing.T) {
+	state := lua.L_newstate()
+	defer lua.close(state)
+
+	FACT_10 :: 3628800
+
+	res := lua.L_dofile(state, #directory + "/factorial.lua")
+	testing.expectf(t, lua.Status(res) == .OK, "Expected L_dofile to return OKAY")
+
+	fact := lua.L_checkinteger(state, -1)
+
+	testing.expectf(t, fact == FACT_10, "Expected factorial(10) to return %v, got %v", FACT_10, fact)
+}
+
+@(test)
+// Test that our bindings didn't get out of sync with the API version
+verify_lua_api_version :: proc(t: ^testing.T) {
+	state := lua.L_newstate()
+	defer lua.close(state)
+
+	version := int(lua.version(state))
+
+	testing.expectf(t, version == lua.VERSION_NUM, "Expected lua.version to return %v, got %v", lua.VERSION_NUM, version)
+}
+
+// Simple context.allocator-based callback for Lua. Use `lua.newstate` to pass the context as user data.
+lua_context_allocator :: proc "c" (ud: rawptr, ptr: rawptr, osize, nsize: c.size_t) -> (buf: rawptr) {
+	old_size := int(osize)
+	new_size := int(nsize)
+	context = (^runtime.Context)(ud)^
+
+	if ptr == nil {
+		data, err := runtime.mem_alloc(new_size)
+		return raw_data(data) if err == .None else nil
+	} else {
+		if nsize > 0 {
+			data, err := runtime.mem_resize(ptr, old_size, new_size)
+			return raw_data(data) if err == .None else nil
+		} else {
+			runtime.mem_free(ptr)
+			return
+		}
+	}
+}