pyright vs pylance issue - backports.strenum

[AbdealiLoKo]

I am trying to use pyright for an existing project, and have a buuunch of issues I am trying to fix.

Like many others - I am trying to use pyright on my github actions and pylance in VSCode.
Note - I already went through: https://github.com/microsoft/pylance-release/blob/main/USING_WITH_PYRIGHT.md

I am getting this error in pyright:

util/constants.py:6:6 - error: Import "backports.strenum" could not be resolved (reportMissingImports)

But I do not see any such problem with pylance in VScode when I open that file.

I have checked that there are no stubs that tpylance provides for backports.strenum at: https://github.com/microsoft/python-type-stubs/tree/main/stubs

So, I was wondering - what is causing the different between pylance and pyright here ?

• pyright: 1.1.348
• vscode: 1.87.0
• vscode pylance extension: Pylance language server 2024.2.2 (pyright version 1.1.348, commit cfb1de0c) starting
• vscode python extension: 2024.2.1

[rchiodo]

If you set pyright to verbose, it should list out the paths it used to search for the import. Like so:

C:\Users\rchiodo>pyright --verbose test.py
Search paths for file:///c%3A/Users/rchiodo
  c:\Users\rchiodo\AppData\Roaming\nvm\v18.17.1\node_modules\pyright\dist\typeshed-fallback\stdlib
  c:\Users\rchiodo
  c:\Users\rchiodo\typings
  c:\Users\rchiodo\AppData\Roaming\nvm\v18.17.1\node_modules\pyright\dist\typeshed-fallback\stubs\...
  c:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0\DLLs
  c:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0\Lib
  c:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0
  c:\Users\rchiodo\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0\LocalCache\local-packages\Python311\site-packages
  c:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0\Lib\site-packages
Found 1 source file
Could not import 'backports' in file 'c:\Users\rchiodo\test.py'
  Looking in stubPath 'file:///c%3A/Users/rchiodo/typings'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo/typings'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/typings'
  Looking in root directory of execution environment 'file:///c%3A/Users/rchiodo'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo'
  Finding python search paths
  Executing interpreter: 'python'
  Skipping 'C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0\python311.zip' because it is not a valid directory
  Received 5 paths from interpreter
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0
    file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Looking in python search path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Looking for typeshed stdlib path
  Looking for typeshed stdlib path
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/AppData/Roaming/nvm/v18.17.1/node_modules/pyright/dist/typeshed-fallback/stdlib'
  Typeshed path not found
  Looking for typeshed third-party path
  Looking for typeshed stubs path
  Typeshed path not found
Could not import 'backports.strenum' in file 'c:\Users\rchiodo\test.py'
  Looking in stubPath 'file:///c%3A/Users/rchiodo/typings'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo/typings'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/typings'
  Looking in root directory of execution environment 'file:///c%3A/Users/rchiodo'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo'
  Finding python search paths
  Executing interpreter: 'python'
  Skipping 'C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0\python311.zip' because it is not a valid directory
  Received 5 paths from interpreter
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0
    file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages
    file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/DLLs'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0'
  Looking in python search path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Attempting to resolve stub package using root path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/AppData/Local/Packages/PythonSoftwareFoundation.Python.3.11_qbz5n2kfra8p0/LocalCache/local-packages/Python311/site-packages'
  Looking in python search path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Attempting to resolve stub package using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Attempting to resolve using root path 'file:///c%3A/Program%20Files/WindowsApps/PythonSoftwareFoundation.Python.3.11_3.11.2288.0_x64__qbz5n2kfra8p0/Lib/site-packages'
  Looking for typeshed stdlib path
  Looking for typeshed stdlib path
  Attempting to resolve using root path 'file:///c%3A/Users/rchiodo/AppData/Roaming/nvm/v18.17.1/node_modules/pyright/dist/typeshed-fallback/stdlib'
  Typeshed path not found
  Looking for typeshed third-party path
  Looking for typeshed stubs path
  Typeshed path not found
pyright 1.1.351
c:\Users\rchiodo\test.py
  c:\Users\rchiodo\test.py:1:8 - error: Import "backports.strenum" could not be resolved (reportMissingImports)
1 error, 0 warnings, 0 informations
Completed in 0.746sec

Then in pylance you could change the import to force a failure and set pylance to verbose. The output in pylance would then show the search paths it used and you could compare the two.

My guess is something in your environment is different:
https://github.com/microsoft/pylance-release/blob/main/USING_WITH_PYRIGHT.md#settings-differences