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False positive reportShadowedImports with PEP562 package-level getattr
Environment data
- Language Server version: v2023.4.40
- OS and version: macos 13.3.1 (also observed on windows)
- Python version (& distribution if applicable, e.g. Anaconda): Python 3.10 installed via homebrew
Code Snippet
The issue occurs for some but not all stdlib imports within the github.com/tornadoweb/tornado repo. The cause appears to be this __getattr__ hook in tornado/init.py
https://github.com/tornadoweb/tornado/blob/dc56f548fb7edfc6697b100cbbfc422fd9784913/tornado/init.py#L63-L67
One import that gives this error is the "import sys" in tornado/test/runtests.py.
Repro Steps
Clone github.com/tornadoweb/tornado, open it in vscode (with python plugins installed with default settings). Open tornado/test/runtests.py and observe the warning reported on the "import sys" line:
"/Users/bdarnell/src/tornado/tornado/__init__.py" is overriding the stdlib module "sys" Pylance reportShadowedImports
Expected behavior
No warning should be emitted.
Actual behavior
A warning is emitted as quoted above.
This is a false positive for multiple reasons:
- The getattr hook raises ImportError for unknown names, so it should not actually shadow anything. (but fair enough, you can't determine that statically)
- Absolute imports have been the default since Python 3.0. The getattr hook in tornado/init.py is only used for imports that specify
tornado.*or relative imports within the tornado package, not this unqualified "import sys" - The warning is occurring in subpackages of tornado, and even when absolute imports were not the default I do not believe there was any name resolution rule that would put this in scope
Logs
(11786) [FG] parsing: /Users/bdarnell/src/tornado/tornado/test/runtests.py (16ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/builtins.pyi [fs read 1ms] (26ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/builtins.pyi (10ms)
(11786) [FG] binding: /Users/bdarnell/src/tornado/tornado/test/runtests.py (2ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/typing.pyi [fs read 0ms] (8ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/typing.pyi (3ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/typing_extensions.pyi [fs read 0ms] (1ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/typing_extensions.pyi (1ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/_typeshed/__init__.pyi [fs read 0ms] (4ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/_typeshed/__init__.pyi (1ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/types.pyi [fs read 0ms] (2ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/types.pyi (2ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/abc.pyi [fs read 0ms] (0ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/abc.pyi (0ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/textwrap.pyi [fs read 1ms] (1ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/textwrap.pyi (0ms)
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/unittest/__init__.pyi [fs read 1ms] (3ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/unittest/__init__.pyi ...
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/unittest/async_case.pyi [fs read 0ms] (1ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/unittest/async_case.pyi (0ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/unittest/__init__.pyi (1ms)
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/sys.pyi [fs read 1ms] (6ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/sys.pyi (2ms)
(11786) [FG] parsing: /Users/bdarnell/src/tornado/tornado/__init__.py (2ms)
(11786) [FG] binding: /Users/bdarnell/src/tornado/tornado/__init__.py (0ms)
(11786) [FG] parsing: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/logging/__init__.pyi [fs read 0ms] (3ms)
(11786) [FG] binding: /Users/bdarnell/.vscode/extensions/ms-python.vscode-pylance-2023.4.40/dist/typeshed-fallback/stdlib/logging/__init__.pyi (1ms)
(11786) [FG] parsing: /var/folders/vg/ff5x6_0x0ds6xnct4sm8q_mh0000gn/T/pyright-11786-sYza27XIScSe/builtins-11786-9Oxiz20yaPGe-.py [fs read 0ms] (17ms)
(11786) [FG] binding: /var/folders/vg/ff5x6_0x0ds6xnct4sm8q_mh0000gn/T/pyright-11786-sYza27XIScSe/builtins-11786-9Oxiz20yaPGe-.py (19ms)
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: setFileClosed
(11786) Background analysis message: analyze
(11786) Background analysis message: setFileOpened
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getDiagnosticsForRange
(11786) Background analysis message: getSemanticTokens full
(11786) [BG(1)] getSemanticTokens full at /Users/bdarnell/src/tornado/tornado/test/runtests.py (7ms)
For the record, this is still occurring with language server version 2027.7.1 (Pylance language server 2024.7.1 (pyright version 1.1.369, commit 1168be71) starting). However, it's moved around a bit. I no longer see it on the import sys line in tornado/test/runtests.py. I still see it in other places, including the import of binascii in httpclient_test.py.
I'm not sure whether this is a useful clue or not, but binascii is imported four times in this codebase (auth.py, web.py, httpclient_test.py, and web_test.py), and three of those times are affected by this bug (the one in web.py is not).
