| commit | d9103dfcf5f2eea6ca277b009b29432341a3b7c9 | [log] [tgz] |
|---|---|---|
| author | Xinhao Yuan <xinhaoyuan@google.com> | Tue May 06 15:48:49 2025 -0700 |
| committer | Copybara-Service <copybara-worker@google.com> | Tue May 06 15:49:43 2025 -0700 |
| tree | d7ad173822f251320aeb816711138defea83110e | |
| parent | 782b979c19ed66b2a1f670ace778bb50ff834729 [diff] |
Export and report crash reproducers from Centipede. Previously when running with Centipede, crash reproducers are saved only when updating the corpus database, otherwise they are never reported to users. Reporting reproducers (with reproduction instructions) has been desired in multiple scenarios, but the feature was only available in the legacy engine. This change implements the feature in FuzzTest/Centipede properly by letting the controller handle the reporting. One observable difference here with the legacy engine is that FuzzTest/Centipede would find and report multiple reproducers in one run. In order to avoid repeatedly reporting similar reproduction instructions, the controller would report the reproducers together at the end of the run, with first lines listing the reproducer IDs and metadata (crash types), followed by a reproduction instruction with a placeholder reproducer path. Users can replace the placeholder with the reported IDs to reproduce actual crashes. PiperOrigin-RevId: 755555620
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.