Apply new input validation to cuml.kernel_ridge

[jcrist]

Fixes #7996.

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📥 Commits

Reviewing files that changed from the base of the PR and between 1ac1c31 and 047eb3e.

📒 Files selected for processing (2)

• python/cuml/cuml_accel_tests/upstream/scikit-learn/xfail-list.yaml
• python/cuml/tests/test_sklearn_compatibility.py

💤 Files with no reviewable changes (2)

• python/cuml/tests/test_sklearn_compatibility.py
• python/cuml/cuml_accel_tests/upstream/scikit-learn/xfail-list.yaml

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📝 Walkthrough

Summary by CodeRabbit

• New Features

  • KernelRidge now supports multi-output regression.

• Improvements

  • Enhanced input validation and processing in KernelRidge.
  • Expanded scikit-learn compatibility with reduced test failures.

Walkthrough

Refactors KernelRidge input handling to use shared check_inputs flow, adds explicit multi-output support, ensures kernel outputs are CuPy arrays, tweaks solver dtype handling, and tightens xfail test expectations for KernelRidge compatibility checks.

Changes

Cohort / File(s)	Summary
KernelRidge implementation python/cuml/cuml/kernel_ridge/kernel_ridge.py	Replaced bespoke input conversion with check_inputs; fit now supports multi-output and preserves input index when storing X_fit_; _get_kernel forces CuPy output; _solve_cholesky_kernel uses cp.asarray; changed dual_coef casting source; added _more_static_tags(); changed @reflect(reset=True) → @reflect(reset="type").
Test xfail mapping python/cuml/cuml_accel_tests/upstream/scikit-learn/xfail-list.yaml, python/cuml/tests/test_sklearn_compatibility.py	Removed multiple KernelRidge xfail entries for input/target/sample-weight validation and certain training permutations, leaving a narrower xfail surface (pickle/readonly_memmap case).

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• Apply new input validation to cuml.multiclass #8017: Migrates estimators to the shared check_inputs flow and switches @reflect(reset=True) to @reflect(reset="type").
• Use new input validation infrastructure for cuml.decomposition. #8006: Similar migration to centralized input-validation utilities and related decorator/output-type adjustments.
• Apply new validation to cuml.random_projection #8009: Applies the same input-validation refactor replacing bespoke converters with check_inputs and decorator change.

Suggested labels

Cython / Python

Suggested reviewers

• csadorf

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 16.67% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: applying new input validation to cuml.kernel_ridge, which aligns with the refactoring of input handling using check_inputs.
Description check	✅ Passed	The description mentions fixing issue #7996, which directly relates to updating cuml.kernel_ridge to new input validation as shown in the changes.
Linked Issues check	✅ Passed	The PR successfully implements the objective from issue #7996 to update cuml.kernel_ridge to new input validation by refactoring fit/predict to use check_inputs, adding multioutput support, and updating xfail test markers.
Out of Scope Changes check	✅ Passed	All changes are in-scope: kernel_ridge.py refactoring for input validation, xfail-list.yaml adjustments reflecting improved compatibility, and test configuration updates removing expected failures that now pass.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

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[jcrist]

/merge