Python 3.7.5 and 3.8.0
A decorator causes inspect.getsource() to return clipped output:



from collections import defaultdict
from functools import wraps
import inspect


def foo(*args):
    def decorator(func):
        @wraps(func)
        def wrapper():
            pass
        return wrapper
    return decorator


@foo(dict(), defaultdict(lambda: 1))
def f():
    pass


print(inspect.getsource(f))



Output:

@foo(dict(), defaultdict(lambda: 1))

Expected output:

@foo(dict(), defaultdict(lambda: 1))
def f():
    pass


These changes to the decorator parameters cause the problem to disappear:

- @foo({}, defaultdict(lambda: 1))
- @foo(dict(), defaultdict(list))

Thanks for the report!

Turns out this was a bug in ``inspect.BlockFinder`` which is responsible for extracting out the source code from a given block. This class was considering ")" inside a decorator call as closing the decorator itself, even when the decorator call was accepting additional arguments that needed parentheses, such as function calls or tuples.

Just submitted a PR https://github.com/python/cpython/pull/17374 to address this issue.