Remove deprecations from 26.04

[jcrist]

• Removes deprecated cuml.common.exceptions namespace
• Removes deprecated support for 1-dimensional X
• Moves mismatched feature names FutureWarnings to exceptions
• Un-xfails a bunch of now passing sklearn compatibility tests

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: bf6497d9-50c2-4ee9-9760-ce5a7a3ffc21

📥 Commits

Reviewing files that changed from the base of the PR and between 5e954f7 and 2462e0d.

📒 Files selected for processing (6)

• python/cuml/cuml/common/exceptions.py
• python/cuml/cuml/internals/validation.py
• python/cuml/tests/test_sklearn_compatibility.py
• python/cuml/tests/test_sklearn_import_export.py
• python/cuml/tests/test_target_encoder.py
• python/cuml/tests/test_validation.py

💤 Files with no reviewable changes (3)

• python/cuml/tests/test_target_encoder.py
• python/cuml/cuml/common/exceptions.py
• python/cuml/tests/test_sklearn_import_export.py

---

📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes

  • Improved input validation with stricter error handling for non-2D inputs and mismatched feature names.
  • Fixed sklearn compatibility checks for multiple estimators.

• Deprecation

  • Removed deprecated NotFittedError import path from cuml.common.exceptions.

• Breaking Changes

  • Invalid input validation now raises errors immediately instead of warnings.

Walkthrough

This pull request removes deprecated deprecation shims and warning-based fallback behaviors across cuML. It eliminates the NotFittedError deprecation shim, converts input validation to raise immediate errors for non-2D inputs instead of warnings, removes xfail markers from sklearn compatibility tests, and updates test files to expect errors rather than warnings.

Changes

Cohort / File(s)	Summary
Deprecation shim removal python/cuml/cuml/common/exceptions.py	Removed NotFittedError module-level deprecation shim, including __all__ export and dynamic __getattr__ that previously emitted FutureWarning and imported from sklearn.
Input validation hardening python/cuml/cuml/internals/validation.py	Converted non-2D input handling from warn-or-error pattern to immediate ValueError; removed deprecated _warn_or_error helper and replaced conditional warnings with direct errors in _get_n_features, _get_feature_names, and check_features.
Test configuration updates python/cuml/tests/test_sklearn_compatibility.py	Removed 45 xfail entries for various estimators' check_fit1d and check_fit2d_predict1d tests; updated TSNE's check_fit2d_predict1d failure reason.
Warning removal from tests python/cuml/tests/test_sklearn_import_export.py, python/cuml/tests/test_target_encoder.py, python/cuml/tests/test_validation.py	Removed warning suppression decorators and tests that validated FutureWarning behavior; updated validation tests to assert ValueError/TypeError instead of FutureWarning.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• Validate that X is 2 dimensional #7889: Overlapping changes to cuml/internals/validation.py's non-2D input handling and related test expectations.
• Forward-merge release/26.04 into main #7894: Also modifies cuml/internals/validation.py to remove warn-or-error fallback and updates tests to expect direct errors.
• Remove deprecation warning in TargetEncoder #7892: Related deprecation and warning removal for TargetEncoder, with corresponding test updates.

Suggested labels

breaking

Suggested reviewers

• divyegala
• betatim
• csadorf

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Remove deprecations from 26.04' directly and clearly summarizes the main purpose of the changeset, which is the removal of deprecated features and APIs.
Description check	✅ Passed	The description is directly related to the changeset, providing specific details about four key removals: deprecated namespace, 1D input support, warnings converted to exceptions, and un-xfailed tests.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[dantegd]

lgtm

[jcrist]

/merge