Add warning for unmatched include/exclude patterns

[Copilot]

Implement warning for unmatched include/exclude patterns

The goal is to raise a warning to stderr when some patterns did not match anything.

Plan:

• Add tracking mechanism to FilterEngine to record which patterns matched at least once
• Modify FilterEngine.matches() to track when patterns successfully match
• Add method to get unmatched patterns from FilterEngine
• Display warnings for unmatched patterns in main() function
• Write tests for the warning functionality
• Run existing tests to ensure no regressions
• Manually test with CLI to verify warnings appear correctly
• Address code review feedback
• Refactor tests to extend existing test files instead of creating new standalone file

Implementation Details:

Changes to filter.py:

• Added _pattern_matched dictionary to track whether each pattern has matched at least once
• Modified matches() method to set the tracking flag when a pattern matches
• Added get_unmatched_patterns() method to return list of unmatched patterns with their rule kinds
• Removed unreachable code in _include_can_match_descendant()

Changes to gpt_copy.py:

• Added warning display at end of main() function to show unmatched patterns to stderr
• Warning format: --include 'pattern' or --exclude 'pattern' for each unmatched pattern

Test changes:

• Extended test_file_filtering.py with 2 FilterEngine unit tests for tracking mechanism
• Extended test_user_issue_exclusion.py with 2 CLI tests for warnings
• Extended test_filter_spec.py with 1 CLI test for warnings in complex scenarios
• Total: 63 tests (58 original + 5 new integrated tests)

Testing:

• All 63 tests pass
• Manual testing confirmed warnings appear correctly for unmatched patterns
• No warnings when all patterns match
• Linting and formatting checks pass
• Code review feedback addressed

Original prompt

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This section details on the original issue you should resolve

<issue_title>raise a warning if an inclusion exclusion pattern is not matching anything</issue_title>
<issue_description>The app should raise a warning to stderr some patterns did not match anything.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes raise a warning if an inclusion exclusion pattern is not matching anything #54

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[simone-viozzi]

instead of adding 5 new tests, extend some of the existing ones

[Copilot]

instead of adding 5 new tests, extend some of the existing ones

Done. I've integrated the tests into existing test files:

• Added 2 FilterEngine unit tests to test_file_filtering.py
• Added 2 CLI warning tests to test_user_issue_exclusion.py
• Added 1 CLI warning test to test_filter_spec.py
• Removed standalone test_unmatched_patterns.py

Total test count is now 63 (down from 65, as 5 new tests were integrated into existing files). All tests pass. (commit 861b730)