Add no_site_packages setting

[davidzwa]

Fixes #7768
Adds main.py logic for the no_site_packages flag. Tested as being subjective to CLI argument (override).

• Add field to Options constructor
• Add Bool key to config_parser.py
• Adjust 2 places in main.py when checking for python executable.
• Add test(s) in PEP 561 test file
• Rebase onto master
• Remove tests in testpep561.py
• Merged new args and mypy.ini parse options for pep561.test
• Add test to pep561.test file
• Run test and add proper messages

Note: run test with the following command

python -m pytest -k testTypedPkg_nositepackages ./mypy

[emmatyping]

Any idea why it's failing on importing typedpkg?

That is the point of no-site-packages, it disables mypy from searching the site-packages directory for installed packages, failing to import typedpkg is the expected result. I think you should change the expected output to be the failure to find typedpkg warning.

[davidzwa]

Not to happy with the ':4' and ':2' messages in the testpep561.py file. Thinking about formatting the message with a line number in the expected_out list. Sound good?

[davidzwa]

@ethanhs I added a test, but I think this is not working correctly. I tried the following variants:

• # flags: no-site-packages
• # mypy: no-site-packages
• # mypy: no-site-packages=true
• # cmd: mypy --no-site-packages

But all give the "testTypedPkg_nositepackages.py:6: note: Revealed type is 'builtins.tuple[builtins.str]'" note instead of an import error. I hope you can take over to find the solution.

[Edit]: I also tried to add [file mypy.ini] and [mypy] followed by no_site_packages=True. This broke the whole test data parsing process.

[emmatyping]

@davidzwa hm, yeah it looks like the test harness doesn't support flags like that. You can probably create a function to parse arguments and call it here and have it parse testcase.input[1] (Since the first line already handles packages). Let me know if that doesn't make sense, or I can do it myself if you wish.

EDIT: oh and the harness will also need to understand mypy.ini files. I'll fix this myself.

[emmatyping]

@davidzwa you should be able to pull my changes from the no-sp-fix branch in my repository.

You can pull the changes with something like:

$ git remote add ethanhs https://github.com/ethanhs/mypy.git
$ git fetch ethanhs
$ git merge ethanhs/no-sp-fix

Let me know if you have any problems.

[davidzwa]

Merged, tomorrow I will look at how to adapt test.
[Note]:

[file mypy.ini]
[mypy]
no_site_packages=True

This will not work. Any other way to build up the file? I just need to insert some escaped string, nothing fancy xD

[emmatyping]

@davidzwa if you look at the test I added, you have to escape the [

So:

\[mypy]
no_site_packages = True

should work. Let me know if it doesn't.

[davidzwa]

I think I should learn to read more carefully, sorry for the miss. You'll find the the two tests sufficient, I'm sure of it!

[emmatyping]

Awesome, thank you for working through this.

[davidzwa]

If you can point me to a related issue including this test-framework, that'd be awesome