No fuzz testing

[sumanjeet0012]

Go has a fuzz test that exercises Cast(), Bytes(), String(), Prefix(), and JSON round-trip with random input. Python has no fuzz testing.

Proposed Solution

Add property-based tests using hypothesis:

from hypothesis import given, strategies as st, settings
from cid import make_cid, CIDv1, CIDv0

@given(st.binary(max_size=200))
@settings(max_examples=1000)
def test_from_bytes_never_crashes(data):
    """from_bytes should raise ValueError, not crash."""
    try:
        make_cid(data)
    except (ValueError, KeyError, TypeError):
        pass  # Any exception is fine, just no crashes

@given(st.binary(min_size=34, max_size=100))
@settings(max_examples=500)
def test_cid_roundtrip_never_crashes(data):
    """CID encode/decode should never crash."""
    try:
        cid = make_cid(data)
        _ = cid.encode()
        _ = str(cid)
        _ = cid.prefix()
    except (ValueError, KeyError, TypeError):
        pass

Related

• Go fuzz test: go-cid cid_fuzz.go