Fix #168: avoid creating duplicate link for addon

[Mateusz-Grzelinski]

In this PR:

• allow user to develop addon even it is placed in directories like (without creating duplicate addon link):
  • \4.2\scripts\addons -> default dir for addons
  • \4.2\extensions\blender_org -> directory indicated by bpy.context.preferences.extensions.repos (list of directories)
• use python3.7 syntax for compability
• ensured (basic) compability with blender 2.80
• remove duplicate links to development (VSCode) directory
• remove broken links in addon and extension dir

Squash merge when ready. Please squash merge after https://github.com/JacquesLucke/blender_vscode/pull/174 - it fixes one more issue with 2.80 compability

About tests:

• they are mostly for me, just nice to have. if you look closesly they are missing many asserts and many errors will slip through when tesing on real blender instance.
• should be cross platform, but tested only on windows
• the tests run outside of blender. bpy and addon_utils are not necessary for tests
• how to run:

  pip install pytest
  cd pythonFile
  $env:PYTHONPATH="./include" # powershell
  pytest -s .\tests 

I could not figure out how to run tests with VS code UI. Works fine with pycharm UI when you mark include directory as source directory.

todo:

• [x] fix tests

Corner cases (for documentation):

• junctions and hard links are difficult to manage
  • python behaves completely differently when touching junction in different python versions!
• link to extension is already present in different repository - remove the link
• link to addon is already present in addon directory but has different name - remove the link
• You are developing extension in addons directory (legacy addon not supported) - make a link
• You are developing addon in extensions directory (no extension support) - make a link
  • why would you do that to me...
• extension has legacy bl_info defined (supportes both legacy and new addon systems) - prefer extension for >4.2, otherwise addon
• extension has legacy bl_info defined (supportes both legacy and new addon systems) BUT user is developing addon in addon directory - treat as addon - do not make a link.

[Mateusz-Grzelinski]

The change should be working now. I tried adding some basic tests, but I did something wrong, because

• if you run tests one by one they work
• if you run the whole file the tests fail - the patch bleeds into other functions. I have no idea how to fix it.

Note: I have basic experience with tests.

pip install pytest
cd pythonFile
$env:PYTHONPATH="./include" # powershell
pytest -s .\tests\blender_vscode\test_load_addons.py::TestIsInAnyAddonDirectory::test_is_in_any_addon_directory # ok
pytest -s .\tests  # 1 ok 5 fail

[Mateusz-Grzelinski]

I think I fixed the tests, but i need to sleep on it.

• rooky mistake: patch calls where they are made
• confusing patching behaviour: you can not patch the attributes in same path in two places (probably)
• removing modules works differently than I anticipated
• mocking global variables is hard
• fixed python 3.7 compability (blender 2.90)

Those tests are just prototypes that helped me find 2 more errors in my code. I am not sure if this is the right way to test (very complicated test for little code)

The tests are prepared to run outside of blender, and without fake-bpy-module

[Mateusz-Grzelinski]

• found even more issues (and fixed them)
• made a super-duper long test. The test is not that complicated but the patching is complicated.

Ehh, enother long evening.

[Mateusz-Grzelinski]

I am pretty sure this patch works as expected. Final test was done by adding addon and extension to both

• \4.2\scripts\addons
• \4.2\extensions\blender_org

as seen on screeshot, all looks ok.

The policy violation was fixed in https://github.com/JacquesLucke/blender_vscode/pull/172/commits/445778f950fcc2e33bd62310e98a31d9c8bdc539

I verified that tests work even if fake-bpy-module is installed.

[Mateusz-Grzelinski]

ugh, breaks older blender. Totally forgot about that. I need to fight the persmission denied error when pip installing and check with blender 2.8 - i think this is the oldest one we support.

Hey, but I am developing this PR on windows, tests should work... Oh, I named the path in Linux style. It does not matter, it works on windows

[Mateusz-Grzelinski]

fixed compability with bledner 2.80. Please squash merge after #174 - it fixes one more issue with 2.80 compability

[Mateusz-Grzelinski]

updated to newest master, ready to merge as 174 was completed.

[Mateusz-Grzelinski]

Covered one more edge case

1. You are developing extension in addons directory
2. extension has legacy bl_info defined (supportes both legacy and new addon systems)
3. then do not create a link (it will be duplicate)

Agr, last changes from other PRs broke the tests...

[Mateusz-Grzelinski]

the tests are fixed. but I just thought about yet another corner case:

• link to extension is already present in different repository - this will cause duplicate
• link to addon is already present in addon directory but has different name - also a duplicate

[Mateusz-Grzelinski]

there are problems with python 3.7 and dealing with junctions in windows. They are not recognized correctly and give different errors than python 3.12

[Mateusz-Grzelinski]

This became very involving change, hopefully this is last iteration and I will merge it on the weekend. Before release Linux needs some testing.

[Mateusz-Grzelinski]

tested on ubuntu 22.04 snap installed blender 4.2. Works fine. Merging.