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How to use fuzz_one_input method in hypothesis

Best Python code snippet using hypothesis

test_fuzz_one_input.py

...23    "buffer_type",24    [bytes, bytearray, memoryview, io.BytesIO],25    ids=attrgetter("__name__"),26)27def test_fuzz_one_input(buffer_type):28    db = InMemoryExampleDatabase()29    seen = []30    seeds = []31    # This is a standard `@given` test, which we can also use as a fuzz target.32    # Note that we specify the DB so we can make more precise assertions,33    # and tighten the phases so we can be sure the failing examples come from fuzzing.34    @given(st.text())35    @settings(database=db, phases=[Phase.reuse, Phase.shrink])36    def test(s):37        seen.append(s)38        assert "\0" not in s, repr(s)39    # Before running fuzz_one_input, there's nothing in `db`, and so the test passes40    # (because example generation is disabled by the custom settings)41    test()42    assert len(seen) == 043    # If we run a lot of random bytestrings through fuzz_one_input, we'll eventually44    # find a failing example.45    with pytest.raises(AssertionError):46        for _ in range(1000):47            buf = bytes(random.getrandbits(8) for _ in range(1000))48            seeds.append(buf)49            test.hypothesis.fuzz_one_input(buffer_type(buf))50    # fuzz_one_input returns False for invalid bytestrings, due to e.g. assume(False)51    assert len(seen) <= len(seeds)52    # `db` contains exactly one failing example, which is either the most53    # recent seed that we tried or the pruned-and-canonicalised form of it.54    (saved_examples,) = db.data.values()55    assert len(saved_examples) == 156    assert sort_key(seeds[-1]) >= sort_key(list(saved_examples)[0])57    # Now that we have a failure in `db`, re-running our test is sufficient to58    # reproduce it, *and shrink to a minimal example*.59    with pytest.raises(AssertionError):60        test()61    assert seen[-1] == "\0"62def test_can_fuzz_with_database_eq_None():63    # This test exists to cover the can't-record-failure branch.64    @given(st.none())65    @settings(database=None)66    def test(s):67        assert False68    with pytest.raises(AssertionError):69        test.hypothesis.fuzz_one_input(b"\x00\x00")70def test_fuzzing_unsatisfiable_test_always_returns_None():71    # There are no examples of `st.none().filter(bool)`, but while the Hypothesis72    # engine would give up, fuzz_one_input will just return None each time.73    @given(st.none().filter(bool))74    @settings(database=None)75    def test(s):76        assert False77    for _ in range(100):78        buf = bytes(random.getrandbits(8) for _ in range(3))79        ret = test.hypothesis.fuzz_one_input(buf)80        assert ret is None81def test_autopruning_of_returned_buffer():82    @given(st.binary(min_size=4, max_size=4))83    @settings(database=None)84    def test(s):85        pass86    # Unused portions of the input buffer are discarded from output.87    # (and canonicalised, but that's a no-op for fixed-length `binary()`)88    assert test.hypothesis.fuzz_one_input(b"deadbeef") == b"dead"89STRAT = st.builds(object)90@given(x=STRAT)91def addx(x, y):92    pass93@given(STRAT)94def addy(x, y):95    pass96def test_can_access_strategy_for_wrapped_test():97    assert addx.hypothesis._given_kwargs == {"x": STRAT}98    assert addy.hypothesis._given_kwargs == {"y": STRAT}99@pytest.mark.parametrize(100    "buffers,db_size",101    [102        ([b"aa", b"bb", b"cc", b"dd"], 1),  # ascending -> only saves first103        ([b"dd", b"cc", b"bb", b"aa"], 4),  # descending -> saves all104        ([b"cc", b"dd", b"aa", b"bb"], 2),  # sawtooth -> saves cc then aa105        ([b"aa", b"bb", b"cc", b"XX"], 2),  # two distinct errors -> saves both106    ],107)108def test_fuzz_one_input_does_not_add_redundant_entries_to_database(buffers, db_size):109    db = InMemoryExampleDatabase()110    seen = []111    @given(st.binary(min_size=2, max_size=2))112    @settings(database=db)113    def test(s):114        seen.append(s)115        assert s != b"XX"116        raise AssertionError117    for buf in buffers:118        with pytest.raises(AssertionError):119            test.hypothesis.fuzz_one_input(buf)120    (saved_examples,) = db.data.values()121    assert seen == buffers...

fuzz.py

Source: fuzz.py

...25    writer = Writer()26    writer.document = doc27    writer.translate()28    return writer.output29def fuzz_one_input(data: bytes) -> None:30    fdp = atheris.FuzzedDataProvider(data)31    src = fdp.ConsumeUnicodeNoSurrogates(sys.maxsize)32    if "\x00" in src:33        return34    try:35        doc = parse_rst(src)36    except:  # noqa: E72237        return38    wrote = write_rst(doc)39    assert wrote is not None40    wrote_publish = publish_string(wrote).decode("utf-8")41    wrote_tree_str = str(parse_rst(wrote))42    src_pubilsh = publish_string(src).decode("utf-8")43    src_tree_str = str(doc)...

ht_fuzz_test.py

Source: ht_fuzz_test.py

1# Fuzz (atheris) + Hypothesis strategies. Seems to combine both fine, but way slower or not adapting enough,2# as it did not find a bug vs using atheris only3from hypothesis import given, strategies as st4import atheris5with atheris.instrument_imports():6    import sys7    import functions8@given(st.text())9def test_not_kirby(s):10    functions.not_kirby(s)11if __name__ == "__main__":12    # see https://github.com/google/oss-fuzz/blob/master/projects/ujson/hypothesis_structured_fuzzer.py13    atheris.Setup(sys.argv, atheris.instrument_func(test_not_kirby.hypothesis.fuzz_one_input))...

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