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SKILL.md 4.3 KB
---
name: refactor-method-complexity-reduce
description: 'Refactor given method `${input:methodName}` to reduce its cognitive complexity to `${input:complexityThreshold}` or below, by extracting helper methods.'
---
# Refactor Method to Reduce Cognitive Complexity
## Objective
Refactor the method `${input:methodName}`, to reduce its cognitive complexity to `${input:complexityThreshold}` or below, by extracting logic into focused helper methods.
## Instructions
1. **Analyze the current method** to identify sources of cognitive complexity:
- Nested conditional statements
- Multiple if-else or switch chains
- Repeated code blocks
- Multiple loops with conditions
- Complex boolean expressions
2. **Identify extraction opportunities**:
- Validation logic that can be extracted into a separate method
- Type-specific or case-specific processing that repeats
- Complex transformations or calculations
- Common patterns that appear multiple times
3. **Extract focused helper methods**:
- Each helper should have a single, clear responsibility
- Extract validation into separate `Validate*` methods
- Extract type-specific logic into handler methods
- Create utility methods for common operations
- Use appropriate access levels (static, private, async)
4. **Simplify the main method**:
- Reduce nesting depth
- Replace massive if-else chains with smaller orchestrated calls
- Use switch statements where appropriate for cleaner dispatch
- Ensure the main method reads as a high-level flow
5. **Preserve functionality**:
- Maintain the same input/output behavior
- Keep all validation and error handling
- Preserve exception types and error messages
- Ensure all parameters are properly passed to helpers
6. **Best practices**:
- Make helper methods static when they don't need instance state
- Use null checks and guard clauses early
- Avoid creating unnecessary local variables
- Consider using tuples for multiple return values
- Group related helper methods together
## Implementation Approach
- Extract helper methods before refactoring the main flow
- Test incrementally to ensure no regressions
- Use meaningful names that describe the extracted responsibility
- Keep extracted methods close to where they're used
- Consider making repeated code patterns into generic methods
## Result
The refactored method should:
- Have cognitive complexity reduced to the target threshold of `${input:complexityThreshold}` or below
- Be more readable and maintainable
- Have clear separation of concerns
- Be easier to test and debug
- Retain all original functionality
## Testing and Validation
**CRITICAL: After completing the refactoring, you MUST:**
1. **Run all existing tests** related to the refactored method and its surrounding functionality
2. **MANDATORY: Explicitly verify test results show "failed=0"**
- **NEVER assume tests passed** - always examine the actual test output
- Search for the summary line containing pass/fail counts (e.g., "passed=X failed=Y")
- **If the summary shows any number other than "failed=0", tests have FAILED**
- If test output is in a file, read the entire file to locate and verify the failure count
- Running tests is NOT the same as verifying tests passed
- **Do not proceed** until you have explicitly confirmed zero failures
3. **If any tests fail (failed > 0):**
- State clearly how many tests failed
- Analyze each failure to understand what functionality was broken
- Common causes: null handling, empty collection checks, condition logic errors
- Identify the root cause in the refactored code
- Correct the refactored code to restore the original behavior
- Re-run tests and verify "failed=0" in the output
- Repeat until all tests pass (failed=0)
4. **Verify compilation** - Ensure there are no compilation errors
5. **Check cognitive complexity** - Confirm the metric is at or below the target threshold of `${input:complexityThreshold}`
## Confirmation Checklist
- [ ] Code compiles without errors
- [ ] **Test results explicitly state "failed=0"** (verified by reading the output)
- [ ] All test failures analyzed and corrected (if any occurred)
- [ ] Cognitive complexity is at or below the target threshold of `${input:complexityThreshold}`
- [ ] All original functionality is preserved
- [ ] Code follows project conventions and standards
License (MIT)
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MIT License Copyright GitHub, Inc. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.