audk/UnitTestFrameworkPkg/Include/Library/FunctionMockLib.h

132 lines
7.1 KiB
C++

/** @file
This header allows the mocking of free (C style) functions using gmock.
Copyright (c) 2023, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef FUNCTION_MOCK_LIB_H_
#define FUNCTION_MOCK_LIB_H_
#include <Library/GoogleTestLib.h>
#include <Library/SubhookLib.h>
#include <type_traits>
//////////////////////////////////////////////////////////////////////////////
// The below macros are the public function mock interface that are intended
// to be used outside this file.
#define MOCK_INTERFACE_DECLARATION(MOCK) \
static MOCK * Instance; \
MOCK (); \
~MOCK ();
#define MOCK_INTERFACE_DEFINITION(MOCK) \
MOCK_STATIC_INSTANCE_DEFINITION (MOCK) \
MOCK_INTERFACE_CONSTRUCTOR (MOCK) \
MOCK_INTERFACE_DECONSTRUCTOR (MOCK)
// Mock function declaration for external functions (i.e. functions to
// mock that do not exist in the compilation unit).
#define MOCK_FUNCTION_DECLARATION(RET_TYPE, FUNC, ARGS) \
MOCK_FUNCTION_TYPE_DEFINITIONS(RET_TYPE, FUNC, ARGS) \
MOCK_METHOD (RET_TYPE, FUNC, ARGS);
// Mock function definition for external functions (i.e. functions to
// mock that do not exist in the compilation unit).
#define MOCK_FUNCTION_DEFINITION(MOCK, FUNC, NUM_ARGS, CALL_TYPE) \
FUNCTION_DEFINITION_TO_CALL_MOCK(MOCK, FUNC, FUNC, NUM_ARGS, CALL_TYPE)
// Mock function declaration for internal functions (i.e. functions to
// mock that already exist in the compilation unit).
#define MOCK_FUNCTION_INTERNAL_DECLARATION(RET_TYPE, FUNC, ARGS) \
MOCK_FUNCTION_DECLARATION(RET_TYPE, FUNC, ARGS) \
MOCK_FUNCTION_HOOK_DECLARATIONS(FUNC)
// Mock function definition for internal functions (i.e. functions to
// mock that already exist in the compilation unit). This definition also
// implements MOCK_FUNC() which is later hooked as FUNC().
#define MOCK_FUNCTION_INTERNAL_DEFINITION(MOCK, FUNC, NUM_ARGS, CALL_TYPE) \
FUNCTION_DEFINITION_TO_CALL_MOCK(MOCK, FUNC, MOCK##_##FUNC, NUM_ARGS, CALL_TYPE) \
MOCK_FUNCTION_HOOK_DEFINITIONS(MOCK, FUNC)
//////////////////////////////////////////////////////////////////////////////
// The below macros are private and should not be used outside this file.
#define MOCK_FUNCTION_HOOK_DECLARATIONS(FUNC) \
static subhook::Hook Hook##FUNC; \
struct MockContainer_##FUNC { \
MockContainer_##FUNC (); \
~MockContainer_##FUNC (); \
}; \
MockContainer_##FUNC MockContainerInst_##FUNC;
// This definition implements a constructor and destructor inside a nested
// class to enable automatic installation of the hooks to the associated
// MOCK_FUNC() when the mock object is instantiated in scope and automatic
// removal when the instantiated mock object goes out of scope.
#define MOCK_FUNCTION_HOOK_DEFINITIONS(MOCK, FUNC) \
subhook :: Hook MOCK :: Hook##FUNC; \
MOCK :: MockContainer_##FUNC :: MockContainer_##FUNC () { \
if (MOCK :: Instance == NULL) \
MOCK :: Hook##FUNC .Install( \
(FUNC##_ret_type *) ::FUNC, \
(FUNC##_ret_type *) MOCK##_##FUNC); \
} \
MOCK :: MockContainer_##FUNC :: ~MockContainer_##FUNC () { \
MOCK :: Hook##FUNC .Remove(); \
} \
static_assert( \
std::is_same<decltype(&::FUNC), decltype(&MOCK##_##FUNC)>::value, \
"Function signature from 'MOCK_FUNCTION_INTERNAL_DEFINITION' macro " \
"invocation for '" #FUNC "' does not match the function signature " \
"of '" #FUNC "' function it is mocking. Mismatch could be due to " \
"different return type, arguments, or calling convention. See " \
"associated 'MOCK_FUNCTION_INTERNAL_DECLARATION' macro invocation " \
"for more details.");
#define MOCK_FUNCTION_TYPE_DEFINITIONS(RET_TYPE, FUNC, ARGS) \
using FUNC##_ret_type = RET_TYPE; \
using FUNC##_type = FUNC##_ret_type ARGS;
// This function definition simply calls MOCK::Instance->FUNC() which is the
// mocked counterpart of the original function. This allows using gmock with
// C free functions (since by default gmock only works with object methods).
#define FUNCTION_DEFINITION_TO_CALL_MOCK(MOCK, FUNC, FUNC_DEF_NAME, NUM_ARGS, CALL_TYPE) \
extern "C" { \
typename MOCK :: FUNC##_ret_type CALL_TYPE FUNC_DEF_NAME( \
GMOCK_PP_REPEAT(GMOCK_INTERNAL_PARAMETER, \
(MOCK :: FUNC##_type), \
NUM_ARGS)) \
{ \
EXPECT_TRUE(MOCK :: Instance != NULL) \
<< "Called '" #FUNC "' in '" #MOCK "' function mock object before " \
<< "an instance of '" #MOCK "' was created in test '" \
<< ::testing::UnitTest::GetInstance()->current_test_info()->name() \
<< "'."; \
return MOCK :: Instance->FUNC( \
GMOCK_PP_REPEAT(GMOCK_INTERNAL_FORWARD_ARG, \
(MOCK :: FUNC##_type), \
NUM_ARGS)); \
} \
}
#define MOCK_STATIC_INSTANCE_DEFINITION(MOCK) MOCK * MOCK :: Instance = NULL;
#define MOCK_INTERFACE_CONSTRUCTOR(MOCK) \
MOCK :: MOCK () { \
EXPECT_TRUE(MOCK :: Instance == NULL) \
<< "Multiple instances of '" #MOCK "' function mock object were " \
<< "created and only one instance is allowed in test '" \
<< ::testing::UnitTest::GetInstance()->current_test_info()->name() \
<< "'."; \
MOCK :: Instance = this; \
}
#define MOCK_INTERFACE_DECONSTRUCTOR(MOCK) \
MOCK :: ~ MOCK () { \
MOCK :: Instance = NULL; \
}
#endif // FUNCTION_MOCK_LIB_H_