Fix 6115282

[sugunav14]

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Additional Information

Summary by CodeRabbit

• Bug Fixes
  • Updated compatibility handling to support Transformers 5.0 while maintaining backward compatibility with earlier versions.

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between e2d29c8 and 37b2706.

📒 Files selected for processing (1)

• modelopt/torch/opt/plugins/transformers.py

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📝 Walkthrough

Walkthrough

The pull request adds Transformers 5.0 API compatibility by introducing explicit version detection and conditionally adjusting the signature of a cached Transformers private loader function. The module checks Transformers version at import time and branches the loader call based on whether the installed version is >= 5.0.

Changes

Transformers 5.0 Compatibility

Layer / File(s)	Summary
Version Detection modelopt/torch/opt/plugins/transformers.py	Adds explicit imports of transformers and Version from packaging.version; defines _TRANSFORMERS_GE_5_0 flag at module level to enable runtime version checks.
Version-Conditional Loader modelopt/torch/opt/plugins/transformers.py	Updates _load_params_and_buffers_into_zero3_model to branch on _TRANSFORMERS_GE_5_0 when calling the cached private _load_state_dict_into_zero3_model loader, passing load_config=True only for Transformers >= 5.0.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Title check	❓ Inconclusive	The title 'Fix 6115282' is vague and does not clearly describe the actual changes made to the codebase, which involve handling a Transformers 5.0 API change.	Update the title to be more specific about the change, such as 'Support Transformers 5.0 API changes in zero3 model loading' to better convey the purpose of the fix.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[codecov]

Codecov Report

❌ Patch coverage is 85.71429% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 65.79%. Comparing base (e2d29c8) to head (37b2706).

Files with missing lines	Patch %	Lines
modelopt/torch/opt/plugins/transformers.py	85.71%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1419       +/-   ##
===========================================
- Coverage   77.40%   65.79%   -11.61%     
===========================================
  Files         476      476               
  Lines       51319    51325        +6     
===========================================
- Hits        39721    33768     -5953     
- Misses      11598    17557     +5959     

Flag	Coverage Δ
examples	32.34% <85.71%> (-9.63%)	⬇️
gpu	27.41% <42.85%> (-33.03%)	⬇️
regression	15.20% <42.85%> (+0.07%)	⬆️
unit	52.56% <42.85%> (-0.01%)	⬇️

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