Function fn

test/functional/feature_taproot.py:636–639

(ctx)

def bitflipper(expr):
    """Return a callable that evaluates expr and returns it with a random bitflip."""
    def fn(ctx):
        sub = deep_eval(ctx, expr)
        assert isinstance(sub, bytes)
        return (int.from_bytes(sub, 'little') ^ (1 << random.randrange(len(sub) * 8))).to_bytes(len(sub), 'little')
    return fn

def zero_appender(expr):