Refactor generateYAML() into focused helper functions

[Copilot]

The generateYAML() function in compiler_yaml.go was a 136-line monolith handling job building, validation, header generation, and body generation. This made it difficult to test components in isolation and harder to maintain.

Changes

Split into three focused helpers:

• buildJobsAndValidate() - Job building and dependency validation
• generateWorkflowHeader() - Header comments with ANSI stripping
• generateWorkflowBody() - Workflow structure (name, triggers, permissions, jobs)

The main generateYAML() now orchestrates these helpers in 30 lines (78% reduction):

func (c *Compiler) generateYAML(data *WorkflowData, markdownPath string) (string, error) {
    // Build all jobs and validate dependencies
    if err := c.buildJobsAndValidate(data, markdownPath); err != nil {
        return "", err
    }

    var yaml strings.Builder
    yaml.Grow(256 * 1024)

    // Generate workflow header comments
    c.generateWorkflowHeader(&yaml, data)

    // Generate workflow body structure
    c.generateWorkflowBody(&yaml, data)

    yamlContent := yaml.String()

    // Post-processing for trial mode
    if c.trialMode && c.hasIssueTrigger(data.On) {
        yamlContent = c.replaceIssueNumberReferences(yamlContent)
    }

    return yamlContent, nil
}

Testing

Added unit tests for each helper function with table-driven test cases. All existing integration tests pass without modification, confirming identical YAML output.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Code Quality] Split generateYAML() function in compiler_yaml.go</issue_title>
<issue_description>## Description

The generateYAML() function in compiler_yaml.go is likely >100 lines and handles multiple concerns including job building, validation, header generation, and body generation. Splitting this function will improve testability, readability, and maintainability.

Current Issues

• Single large function handling multiple responsibilities
• Difficult to test individual components in isolation
• Complex logic flow makes maintenance challenging
• Violates single responsibility principle

Suggested Changes

Extract the main YAML generation function into smaller, focused helper methods:

1. buildJobsAndValidate(data, markdownPath) error

   • Handle job building and validation logic
   • Return early if validation fails
   • Can be unit tested independently

2. generateWorkflowHeader(yaml, data) error

   • Generate workflow metadata and header section
   • Isolated header generation logic
   • Easy to test with different data structures

3. generateWorkflowBody(yaml, data) error

   • Generate workflow body content
   • Focused on body structure only
   • Testable separately from header

Files Affected

• pkg/workflow/compiler_yaml.go (currently 510 lines)
• pkg/workflow/compiler_yaml_test.go (add new test cases for extracted functions)

Success Criteria

• generateYAML() function is split into 3-4 smaller functions
• Each extracted function has a single, clear responsibility
• All existing tests pass without modification
• New unit tests added for each extracted function
• Code complexity is reduced (easier to understand each piece)
• No change in compiled YAML output (identical functionality)

Benefits

• Testability: Each component can be tested in isolation
• Readability: Smaller functions are easier to understand
• Maintainability: Changes to one concern don't affect others
• Reusability: Helper functions can be reused if needed
• Debugging: Easier to identify issues in specific areas

Impact

• Estimated Effort: 2-3 hours
• Risk: Low (preserve existing behavior, add tests)
• Value: High (significantly improves code quality)

Source

Extracted from Daily Compiler Code Quality Report discussion githubnext/gh-aw#12164

Priority

Medium - Improves code organization and testability, but not blocking functionality.

AI generated by Discussion Task Miner - Code Quality Improvement Agent

• expires on Feb 11, 2026, 5:10 AM UTC

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

• Fixes [Code Quality] Split generateYAML() function in compiler_yaml.go #12173

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