[CI] Fix mypy for vllm/distributed

[yewentao256]

Purpose

Part of the #26533

Test

(wentao) wentao@dgxB200-09:~/vllm-source$ pre-commit run --hook-stage manual mypy-3.10 -a
Run mypy for Python 3.10.................................................Passed

[gemini-code-assist]

Code Review

This pull request addresses potential NoneType errors in custom_all_reduce.py and symm_mem.py by adding checks for the return value of current_platform.get_device_capability(). This is a critical fix that improves the robustness of the distributed communicators, preventing crashes on platforms where device capability might not be available. The associated change in tools/pre_commit/mypy.py to enable stricter type checking for the vllm/distributed directory is a good practice that likely helped identify these issues. The changes are well-implemented and correct.

[hmellor]

Looks like there are new followed imports that need resolving. You can run the CI version with pre-commit run --hook-stage manual mypy-3.10 -a

[yewentao256]

@hmellor CC

[hmellor]

I made some tweaks which should make this area a bit more robust. Let's see if CI agrees

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @yewentao256.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork