Today, I went to Ruff playground, enabled PLR1711 (useless-return) rule and pasted this code:

def f() -> int:
    print()
    return None

In Diagnostics tab I saw only Everything is looking good!. I then removed -> int for the code to be:

def f():
    print()
    return None

and saw Useless `return` statement at end of function (PLR1711) [Ln 3, Col 5]. Ruff complained in the same way when I annotated function to return None:

def f() -> None:
    print()
    return None

All the same goes for cases with return instead of return None. Is this an intended behavior? If it is, I think the documentation on this rule should inform about this.

I have checked how pylint handles such cases by running cell with the following in fresh google colab runtime:

!pip install pylint>/dev/null
!printf 'def f() -> int:\n    print()\n    return None' > a.py
!pylint --version && pylint --disable C a.py

I got

pylint 3.3.1
astroid 3.3.5
Python 3.10.12 (main, Sep 11 2024, 15:47:36) [GCC 11.4.0]
************* Module a
a.py:1:0: R1711: Useless return at end of function or method (useless-return)

-----------------------------------
Your code has been rated at 6.67/10

So how can I get ruff to complain about useless return statements in cases when function is annotated to return not None? Do we have to wait for an update for this?

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