Google Test: Parameterized tests which use an existing test fixture class?

Question

I have a test fixture class which is currently used by many tests.

#include <gtest/gtest.h>
class MyFixtureTest : public ::testing::Test {
  void SetUp() { ... }
};

I would like to create a parameterized test which also uses all that MyFixtureTest has to offer, without needing to change all my existing tests.

How do I do that?

I have found similar discussions on the web, but have not fully understood their answers.

Answer 1

This question is now answered in the Google Test documentation (the answer from VladLosev is technically correct, but perhaps slightly more work)

Specifically, when you want to add parameters to a pre-existing fixture class, you can do

class MyFixtureTest : public ::testing::Test {
  ...
};
class MyParamFixtureTest : public MyFixtureTest,
                           public ::testing::WithParamInterface<MyParameterType> {
  ...
};

TEST_P(MyParamFixtureTest, MyTestName) { ... }