def METHOD_NAME(rule_runner: RuleRunner) -> None:
    rule_runner.set_options(
        [
            "--cc-c-compiler-flags=-std=c89",
            "--cc-c-definitions=-DUNIT_TESTING",
        ],
        env_inherit={"PATH"},
    )
    c_toolchain = rule_runner.request(CCToolchain, [CCToolchainRequest(CCLanguage.C)])
    assert c_toolchain.compiler.endswith(
        (
            "gcc",
            "clang",
        )
    )
    assert "-std=c89" in c_toolchain.compiler_flags
    assert "UNIT_TESTING" in c_toolchain.compiler_definitions
    rule_runner.set_options(
        [
            "--cc-cxx-compiler-flags=-std=c++20",
            "--cc-cxx-definitions=-DUNIT_TESTING",
        ],
        env_inherit={"PATH"},
    )
    cxx_toolchain = rule_runner.request(CCToolchain, [CCToolchainRequest(CCLanguage.CXX)])
    assert cxx_toolchain.compile_command[0].endswith(
        (
            "gcc++",
            "clang++",
        )
    )
    assert "-std=c++20" in cxx_toolchain.compiler_flags
    assert "UNIT_TESTING" in cxx_toolchain.compiler_definitions