cargo-fuzztest: support fuzzing a fuzztest. - Add an optional test_path field to CargoFuzzTestOptions and implement test_filter() to support running specific fuzztest targets. - Add --centipede-binary-path CLI flag to CargoFuzzTestOptions and forward it via FUZZTEST_CENTIPEDE_BINARY_PATH environment variable to compiled test processes. - Update FuzztestRunner::build_run_command in cargo-fuzztest to append exact matching arguments when a specific test target is selected. - Forward configured fuzzing durations (both finite durations and indefinite fuzzing via inf) to child test executables using environment variables. - Add unit and e2e integration tests for targeted execution and command flag propagation. PiperOrigin-RevId: 964850072
FuzzTest is a C++ testing framework for writing and executing fuzz tests, which are property-based tests executed using coverage-guided fuzzing under the hood. Fuzz tests are like regular unit tests, but more generic and more powerful. Instead of saying: “for this specific input, we expect this specific output”, we can say: “for these types of input, we expect this generic property to be true”. For example:
void MyApiAlwaysSucceedsOnPositiveIntegers(int i) { bool success = MyApi(i); EXPECT_TRUE(success); } FUZZ_TEST(MyApiTest, MyApiAlwaysSucceedsOnPositiveIntegers) .WithDomains(/*i:*/fuzztest::Positive<int>());
It is our latest fuzz testing technology and the successor of previously used fuzzing tools, such as libFuzzer. It allows you to write powerful fuzz tests more easily than with previously used fuzz targets. You can use it together with GoogleTest, or other unit testing frameworks, allowing you to write fuzz test side by side with regular unit tests, and just as easily.
It is a first-of-its-kind tool that bridges the gap between fuzzing and property-based testing, as it is both:
FuzzTest is for everyone who writes C++ code. (Currently, only C++ is supported.) Fuzz testing is a proven testing technique that has found tens of thousands of bugs. With the FuzzTest framework writing these tests becomes a breeze. Because fuzz tests are more generic, they are more powerful than regular unit tests. They can find tricky edge cases automatically for us, edge cases that most likely we would never think of.
You can write fuzz tests as easily as you write unit tests using GoogleTest for example. Simply use the FUZZ_TEST macro like you would use GoogleTest's TEST macro.
At Google, FuzzTest is widely used and software engineers love it. It has replaced the old style of writing fuzz targets.
To get started, read the Quickstart with Bazel or Quickstart with CMake, then take a look at the Overview and the Codelab.
Once you have a high level understanding about fuzz tests, consider reading the rest of the documentation, including the:
If you have a question or encounter a bug, please file an issue on GitHub.