astroid-4.0.0 does not resolve PySide6.QtCore.QTimer::timeout.connect

[owillebo]

Astroid 4 gives E1101: Method '<no-name>' has no 'connect' member (no-member) for PySide6.QtCore.QTimer::timeout.connect

reproduce.bat

RMDIR /S /Q .venv
ERASE test.py
python -m venv .venv
CALL .venv\Scripts\activate
python -m pip install pylint PySide6
python -m pip freeze
pylint --version
(
    ECHO """astroid-4.0.0 does not resolve PySide6.QtCore.QTimer::timeout.connect."""
    ECHO import PySide6.QtCore
    ECHO(
    ECHO timer = PySide6.QtCore.QTimer(^)
    ECHO timer.timeout.connect(lambda:None^)
) > test.py
REM ~ Astroid 3 has nothing to report.
pylint --extension-pkg-allow-list=PySide6.QtCore test.py
REM ~ Install latest astroid (incompatible with current pylint).
python -m pip install -U astroid
REM ~ Astroid 4 does not resolve PySide6.QtCore.QTimer::timeout.connect.
pylint --extension-pkg-allow-list=PySide6.QtCore test.py

output

C:\Temp>RMDIR /S /Q .venv 
The system cannot find the file specified.

C:\Temp>ERASE test.py 
Could Not Find C:\Temp\test.py

C:\Temp>python -m venv .venv 

C:\Temp>CALL .venv\Scripts\activate 
Collecting pylint
  Using cached pylint-3.3.9-py3-none-any.whl.metadata (12 kB)
Collecting PySide6
  Using cached pyside6-6.9.3-cp39-abi3-win_amd64.whl.metadata (5.5 kB)
Collecting astroid<=3.4.0.dev0,>=3.3.8 (from pylint)
  Using cached astroid-3.3.11-py3-none-any.whl.metadata (4.4 kB)
Collecting colorama>=0.4.5 (from pylint)
  Using cached colorama-0.4.6-py2.py3-none-any.whl.metadata (17 kB)
Collecting dill>=0.3.6 (from pylint)
  Using cached dill-0.4.0-py3-none-any.whl.metadata (10 kB)
Collecting isort!=5.13,<7,>=4.2.5 (from pylint)
  Using cached isort-6.1.0-py3-none-any.whl.metadata (12 kB)
Collecting mccabe<0.8,>=0.6 (from pylint)
  Using cached mccabe-0.7.0-py2.py3-none-any.whl.metadata (5.0 kB)
Collecting platformdirs>=2.2 (from pylint)
  Using cached platformdirs-4.4.0-py3-none-any.whl.metadata (12 kB)
Collecting tomlkit>=0.10.1 (from pylint)
  Using cached tomlkit-0.13.3-py3-none-any.whl.metadata (2.8 kB)
Collecting shiboken6==6.9.3 (from PySide6)
  Using cached shiboken6-6.9.3-cp39-abi3-win_amd64.whl.metadata (2.5 kB)
Collecting PySide6_Essentials==6.9.3 (from PySide6)
  Using cached pyside6_essentials-6.9.3-cp39-abi3-win_amd64.whl.metadata (3.8 kB)
Collecting PySide6_Addons==6.9.3 (from PySide6)
  Using cached pyside6_addons-6.9.3-cp39-abi3-win_amd64.whl.metadata (4.1 kB)
Using cached pylint-3.3.9-py3-none-any.whl (523 kB)
Using cached astroid-3.3.11-py3-none-any.whl (275 kB)
Using cached isort-6.1.0-py3-none-any.whl (94 kB)
Using cached mccabe-0.7.0-py2.py3-none-any.whl (7.3 kB)
Using cached pyside6-6.9.3-cp39-abi3-win_amd64.whl (561 kB)
Using cached pyside6_addons-6.9.3-cp39-abi3-win_amd64.whl (160.7 MB)
Using cached pyside6_essentials-6.9.3-cp39-abi3-win_amd64.whl (73.6 MB)
Using cached shiboken6-6.9.3-cp39-abi3-win_amd64.whl (1.2 MB)
Using cached colorama-0.4.6-py2.py3-none-any.whl (25 kB)
Using cached dill-0.4.0-py3-none-any.whl (119 kB)
Using cached platformdirs-4.4.0-py3-none-any.whl (18 kB)
Using cached tomlkit-0.13.3-py3-none-any.whl (38 kB)
Installing collected packages: tomlkit, shiboken6, platformdirs, mccabe, isort, dill, colorama, astroid, PySide6_Essentials, pylint, PySide6_Addons, PySide6

Successfully installed PySide6-6.9.3 PySide6_Addons-6.9.3 PySide6_Essentials-6.9.3 astroid-3.3.11 colorama-0.4.6 dill-0.4.0 isort-6.1.0 mccabe-0.7.0 platformdirs-4.4.0 pylint-3.3.9 shiboken6-6.9.3 tomlkit-0.13.3
astroid==3.3.11
colorama==0.4.6
dill==0.4.0
isort==6.1.0
mccabe==0.7.0
platformdirs==4.4.0
pylint==3.3.9
PySide6==6.9.3
PySide6_Addons==6.9.3
PySide6_Essentials==6.9.3
shiboken6==6.9.3
tomlkit==0.13.3
pylint 3.3.9
astroid 3.3.11
Python 3.13.7 (tags/v3.13.7:bcee1c3, Aug 14 2025, 14:15:11) [MSC v.1944 64 bit (AMD64)]

--------------------------------------------------------------------
Your code has been rated at 10.00/10 (previous run: 0.00/10, +10.00)

Requirement already satisfied: astroid in c:\temp\.venv\lib\site-packages (3.3.11)
Collecting astroid
  Using cached astroid-4.0.0-py3-none-any.whl.metadata (4.4 kB)
Using cached astroid-4.0.0-py3-none-any.whl (276 kB)
Installing collected packages: astroid
  Attempting uninstall: astroid
    Found existing installation: astroid 3.3.11
    Uninstalling astroid-3.3.11:
      Successfully uninstalled astroid-3.3.11
ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
pylint 3.3.9 requires astroid<=3.4.0.dev0,>=3.3.8, but you have astroid 4.0.0 which is incompatible.
Successfully installed astroid-4.0.0
************* Module test
test.py:5:0: E1101: Method '<no-name>' has no 'connect' member (no-member)

--------------------------------------------------------------------
Your code has been rated at 0.00/10 (previous run: 10.00/10, -10.00)

[owillebo]

Same for pylint 4.0.0

RMDIR /S /Q .venv
ERASE test.py
python -m venv .venv
CALL .venv\Scripts\activate
python -m pip install pylint PySide6
python -m pip freeze
pylint --version
(
    ECHO """astroid-4.0.0 does not resolve PySide6.QtCore.QTimer::timeout.connect."""
    ECHO import PySide6.QtCore
    ECHO(
    ECHO timer = PySide6.QtCore.QTimer(^)
    ECHO timer.timeout.connect(lambda:None^)
) > test.py
REM ~ Astroid 4 does not resolve PySide6.QtCore.QTimer::timeout.connect.
pylint --extension-pkg-allow-list=PySide6.QtCore test.py

C:\Temp>RMDIR /S /Q .venv 
The system cannot find the file specified.

C:\Temp>ERASE test.py 
Could Not Find C:\Temp\test.py

C:\Temp>python -m venv .venv 

C:\Temp>CALL .venv\Scripts\activate 
Collecting pylint
  Using cached pylint-4.0.0-py3-none-any.whl.metadata (12 kB)
Collecting PySide6
  Using cached pyside6-6.10.0-cp39-abi3-win_amd64.whl.metadata (5.5 kB)
Collecting astroid<=4.1.dev0,>=4.0.1 (from pylint)
  Using cached astroid-4.0.1-py3-none-any.whl.metadata (4.4 kB)
Collecting colorama>=0.4.5 (from pylint)
  Using cached colorama-0.4.6-py2.py3-none-any.whl.metadata (17 kB)
Collecting dill>=0.3.6 (from pylint)
  Using cached dill-0.4.0-py3-none-any.whl.metadata (10 kB)
Collecting isort!=5.13,<8,>=5 (from pylint)
  Using cached isort-7.0.0-py3-none-any.whl.metadata (11 kB)
Collecting mccabe<0.8,>=0.6 (from pylint)
  Using cached mccabe-0.7.0-py2.py3-none-any.whl.metadata (5.0 kB)
Collecting platformdirs>=2.2 (from pylint)
  Using cached platformdirs-4.5.0-py3-none-any.whl.metadata (12 kB)
Collecting tomlkit>=0.10.1 (from pylint)
  Using cached tomlkit-0.13.3-py3-none-any.whl.metadata (2.8 kB)
Collecting shiboken6==6.10.0 (from PySide6)
  Using cached shiboken6-6.10.0-cp39-abi3-win_amd64.whl.metadata (2.5 kB)
Collecting PySide6_Essentials==6.10.0 (from PySide6)
  Using cached pyside6_essentials-6.10.0-cp39-abi3-win_amd64.whl.metadata (3.8 kB)
Collecting PySide6_Addons==6.10.0 (from PySide6)
  Using cached pyside6_addons-6.10.0-cp39-abi3-win_amd64.whl.metadata (4.1 kB)
Using cached pylint-4.0.0-py3-none-any.whl (535 kB)
Using cached astroid-4.0.1-py3-none-any.whl (276 kB)
Using cached isort-7.0.0-py3-none-any.whl (94 kB)
Using cached mccabe-0.7.0-py2.py3-none-any.whl (7.3 kB)
Using cached pyside6-6.10.0-cp39-abi3-win_amd64.whl (564 kB)
Using cached pyside6_addons-6.10.0-cp39-abi3-win_amd64.whl (164.8 MB)
Using cached pyside6_essentials-6.10.0-cp39-abi3-win_amd64.whl (74.4 MB)
Using cached shiboken6-6.10.0-cp39-abi3-win_amd64.whl (1.2 MB)
Using cached colorama-0.4.6-py2.py3-none-any.whl (25 kB)
Using cached dill-0.4.0-py3-none-any.whl (119 kB)
Using cached platformdirs-4.5.0-py3-none-any.whl (18 kB)
Using cached tomlkit-0.13.3-py3-none-any.whl (38 kB)
Installing collected packages: tomlkit, shiboken6, platformdirs, mccabe, isort, dill, colorama, astroid, PySide6_Essentials, pylint, PySide6_Addons, PySide6

Successfully installed PySide6-6.10.0 PySide6_Addons-6.10.0 PySide6_Essentials-6.10.0 astroid-4.0.1 colorama-0.4.6 dill-0.4.0 isort-7.0.0 mccabe-0.7.0 platformdirs-4.5.0 pylint-4.0.0 shiboken6-6.10.0 tomlkit-0.13.3
astroid==4.0.1
colorama==0.4.6
dill==0.4.0
isort==7.0.0
mccabe==0.7.0
platformdirs==4.5.0
pylint==4.0.0
PySide6==6.10.0
PySide6_Addons==6.10.0
PySide6_Essentials==6.10.0
shiboken6==6.10.0
tomlkit==0.13.3
pylint 4.0.0
astroid 4.0.1
Python 3.13.8 (tags/v3.13.8:a15ae61, Oct  7 2025, 12:34:25) [MSC v.1944 64 bit (AMD64)]
************* Module test
test.py:5:0: E1101: Method '<no-name>' has no 'connect' member (no-member)

------------------------------------------------------------------
Your code has been rated at 0.00/10 (previous run: 0.00/10, +0.00)

[jorisvr]

I have the same issue: When using Pylint with PySide6, I get heaps of false-positive E1101.

This issue seems newly introduced in Astroid 4.
The example works fine with Astroid 3.3.11.

It seems that two separate things are going wrong:

• The special handling for Qt signals in module astroid.brain.brain_qt is broken.
  The condition cls.qname() == "Signal" fails because the class names appear as fully qualified names in Astroid 4 (i.e. PySide6.QtWidgets.widget_name.Signal instead of just Signal).

• While building method descriptors, Astroid no longer detects the name of Qt signals, instead assigning the label <no-name> to all signals.
  The string <no-name> originates in astroid.raw_building.object_build_methoddescriptor().
  Astroid 3.3.11 avoided this by using a local name as a last resort for nameless methods:
  getattr(member, "__name__", None) or localname.
  But Astroid 4 no longer has this trick. It just assigns <no-name>.

It looks like pull request pylint-dev/astroid#2863 was closed without merging.
But that PR seems to fix the false-positive E1101 in the example above.
Any idea why it was not merged?

[Pierre-Sassoulas]

Thank you for looking into It. It look like the implementer (cleared their github backlog?) and closed the PR. Someone can probably take over.

[emmanuel-ferdman]

Hi @Pierre-Sassoulas @jorisvr, I'm happy to pick this up again - my PR pylint-dev/astroid#2863 was closed when I accidentally deleted my fork, not intentionally (but it did solve the issues). Regarding the astroid plugin suggestion: I looked into it but there's no plugin infrastructure (no entry point discovery, all brains are explicitly imported in helpers.py) and no existing examples to follow since this would be the first astroid plugin ever. I'm happy to recreate PR pylint-dev/astroid#2863 as a direct fix to brain_qt.py, or if a plugin approach is preferred, I'd welcome some guidance on how to approch this task.

[Pierre-Sassoulas]

We need a new issue (or another pre-existing i don't remember) to talk about plugin, this is a big design task.

[emmanuel-ferdman]

@owillebo @jorisvr pylint-qt plugin was just released and is available on PyPI! 🎉
It fixes those Qt false-positives. Please give it a try:

pip install pylint-qt
pylint --load-plugins=pylint_qt --extension-pkg-allow-list=PySide6 your_code.py

Or in pyproject.toml:

[tool.pylint.main]
load-plugins = ["pylint_qt"]
extension-pkg-allow-list = ["PySide6"]

repo: https://github.com/pylint-dev/pylint-qt

[owillebo]

Thanks for all your work!

We still get an issue with QTimer when added to a class member list, see #2

[jorisvr]

pylint-qt plugin was just released and is available on PyPI!

Thanks! This does indeed fix these issues in my codebase.
I find that the new plugin introduces other false positives which I reported separately: #2