atheris

# Atheris ## Contract | Field | Bound contract | |---|---| | Trigger | User needs coverage-guided fuzzing for Python code or a Python native extension using Atheris. | | Authority | Reversible local: writes only the Atheris harness file, a corpus directory, and when required for dependency management `pyproject.toml` and `uv.lock` in the harness directory; rollback is deleting the harness file and corpus directory and restoring `pyproject.toml` and `uv.lock` to their pre-run state. No remote mutation. No source under test is mutated. | | Side effect | Local writes: a `fuzz.py` (or named) harness, a `corpus/` directory of seed and crash artifacts, and a transient fuzzing process. | | Done | Atheris executes an instrumented target through a deterministic `TestOneInput` harness, reports coverage, and any saved crash artifact reproduces the same failure when replayed. | ## Inputs - Target: the Python function or module to fuzz, or the Python C extension to fuzz. Required. - Target kind: pure Python, or native C extension. Required; it selects the instrumentation and build path. - Expected exceptions: the exception types the target legitimately raises on bad input, so the harness catches them instead of crashing. Optional but recommended. - Seed corpus: initial input files for `corpus/`. Optional; Atheris can start empty. - Time/length budget: `-max_total_time` and `-max_len` values. Optional; defaults are libFuzzer defaults. - Sanitizers: whether AddressSanitizer and/or Undef...