How can I run type checking on this library?

[jack-jjm]

How can I run static type checking on this library? It has a bunch of type annotations, but they don't seem to work with mypy. To be clear, I'm talking about running mypy on the code in this repository, not in my own code that imports this library. Here's a sample of the errors I see:

/home/jack/Code/DiscordPy/Codebase/discord/enums.py:78: error: "namedtuple()" expects a string literal as the first argument
/home/jack/Code/DiscordPy/Codebase/discord/enums.py:95: error: Cannot override instance variable (previously declared on base class "type") with class variable
/home/jack/Code/DiscordPy/Codebase/discord/enums.py:100: error: Variable "typing_extensions.Self" is not valid as a type
/home/jack/Code/DiscordPy/Codebase/discord/enums.py:100: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
/home/jack/Code/DiscordPy/Codebase/discord/enums.py:101: error: Need type annotation for "value_mapping" (hint: "value_mapping: Dict[<type>, <type>] = ...")
/home/jack/Code/DiscordPy/Codebase/discord/enums.py:425: error: Missing return statement
/home/jack/Code/DiscordPy/Codebase/discord/flags.py:56: error: Variable "typing_extensions.Self" is not valid as a type
/home/jack/Code/DiscordPy/Codebase/discord/flags.py:56: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases
/home/jack/Code/DiscordPy/Codebase/discord/flags.py:122: error: Variable "typing_extensions.Self" is not valid as a type
/home/jack/Code/DiscordPy/Codebase/discord/flags.py:122: note: See https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases

[Rapptz]

This repository doesn't use mypy as it's currently both slow and buggy. It uses Pyright/Pylance instead.

[jack-jjm]

Thanks! I installed Pyright, but I'm still getting errors, am I running it in the intended way? If I run pyright . in the root of this repo, I get (among other errors):

/home/jack/Code/DiscordPy/Codebase/setup.py
  /home/jack/Code/DiscordPy/Codebase/setup.py:10:92 - error: "group" is not a known member of "None" (reportOptionalMemberAccess)
/home/jack/Code/DiscordPy/Codebase/discord/voice_client.py
  /home/jack/Code/DiscordPy/Codebase/discord/voice_client.py:77:26 - warning: Unnecessary "# type: ignore" comment
  /home/jack/Code/DiscordPy/Codebase/discord/voice_client.py:78:25 - warning: Unnecessary "# type: ignore" comment
/home/jack/Code/DiscordPy/Codebase/discord/app_commands/models.py
  /home/jack/Code/DiscordPy/Codebase/discord/app_commands/models.py:448:22 - error: Cannot assign member "value" for type "Choice[ChoiceT@Choice]"
    Type "str | int | float" cannot be assigned to type "ChoiceT@Choice" (reportGeneralTypeIssues)

I'm on Python 3.8, if that matters.

[Rapptz]

Errors are bound to happen since type checkers are constantly moving and can get buggy. The setup.py ones are mostly irrelevant since it's not type checked and the unnecessary type ignore comments are just warnings. The last remaining errors can be looked at some point.

Type checking is done via CI for set pyright versions, since tracking latest all the time would cause CI to fail due to pyright bugs, which we historically report and wait to get fixed. Anyway that's how you run a type checker with the repository.

[jack-jjm]

Sorry, I was running it the wrong way - it looks like if you give it that . as an argument it basically ignores the pyproject.toml. Just running pyright with no arguments gives me only 2 errors (down from 62):

No configuration file found.
pyproject.toml file found at /home/jack/Code/DiscordPy/Codebase.
Loading pyproject.toml file at /home/jack/Code/DiscordPy/Codebase/pyproject.toml
Assuming Python platform Linux
stubPath /home/jack/Code/DiscordPy/Codebase/typings is not a valid directory.
Searching for source files
Found 115 source files
pyright 1.1.278
/home/jack/Code/DiscordPy/Codebase/discord/voice_client.py
  /home/jack/Code/DiscordPy/Codebase/discord/voice_client.py:77:26 - warning: Unnecessary "# type: ignore" comment
  /home/jack/Code/DiscordPy/Codebase/discord/voice_client.py:78:25 - warning: Unnecessary "# type: ignore" comment
/home/jack/Code/DiscordPy/Codebase/discord/app_commands/models.py
  /home/jack/Code/DiscordPy/Codebase/discord/app_commands/models.py:448:22 - error: Cannot assign member "value" for type "Choice[ChoiceT@Choice]"
    Type "str | int | float" cannot be assigned to type "ChoiceT@Choice" (reportGeneralTypeIssues)
/home/jack/Code/DiscordPy/Codebase/discord/ext/commands/cog.py
  /home/jack/Code/DiscordPy/Codebase/discord/ext/commands/cog.py:378:67 - warning: Unnecessary "# type: ignore" comment
/home/jack/Code/DiscordPy/Codebase/discord/ext/commands/core.py
  /home/jack/Code/DiscordPy/Codebase/discord/ext/commands/core.py:454:27 - error: Cannot assign member "_cog" for type "Command[CogT@Command, P@Command, T@Command]"
    Type "None" cannot be assigned to type "CogT@Command" (reportGeneralTypeIssues)
2 errors, 3 warnings, 0 informations 
Completed in 13.032sec

Just the errors, for readability:

.../discord/app_commands/models.py:448:22 - error: Cannot assign member "value" for type "Choice[ChoiceT@Choice]"
.../discord/ext/commands/core.py:454:27 - error: Cannot assign member "_cog" for type "Command[CogT@Command, P@Command, T@Command]"

And those two errors go away when I use pyright 1.1.265 (the version specified in lint.yml in this repo), so looks like I got it right this time. Thanks for the help.