Refector prepare_inputs in model_runner_v1.py

[ChenTaoyu-SJTU]

What this PR does / why we need it?

Refector prepare_inputs in model_runner_v1.py for more easy read.

Does this PR introduce any user-facing change?

NO

How was this patch tested?

PASS CI

• vLLM version: v0.10.1.1
• vLLM main: vllm-project/vllm@e599e2c

[gemini-code-assist]

Code Review

This pull request refactors the _prepare_inputs method in model_runner_v1.py to improve readability by extracting a helper function and using more idiomatic Python. The changes are generally good and achieve the stated goal. I have found one instance of redundant computation that can be removed to further improve the code's clarity and performance.

[github-actions]

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[codecov]

Codecov Report

❌ Patch coverage is 3.33333% with 29 lines in your changes missing coverage. Please review.
✅ Project coverage is 72.91%. Comparing base (4c90fa7) to head (038d952).
⚠️ Report is 13 commits behind head on main.

Files with missing lines	Patch %	Lines
vllm_ascend/worker/model_runner_v1.py	3.33%	29 Missing ⚠️

❌ Your patch status has failed because the patch coverage (3.33%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2750      +/-   ##
==========================================
- Coverage   72.99%   72.91%   -0.09%     
==========================================
  Files         153      153              
  Lines       21331    21397      +66     
==========================================
+ Hits        15571    15601      +30     
- Misses       5760     5796      +36     

Flag	Coverage Δ
unittests	72.91% <3.33%> (-0.09%)	⬇️

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