🔍 Changed Methods Only

Early PR and commit agents determine which code to generate tests for

This document explains how the --changed-methods-only flag and the CHANGED_METHODS_ONLY environment variable affect test generation behavior.

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🧠 Core Test Selection Logic

At a high level, Early always starts from the same base logic:

• Identify public methods
• Filter methods below the coverage threshold
  (currently treated as zero coverage)
• Generate tests only for methods that meet these criteria

The changed-methods-only setting adds an additional filter layer on top of this logic.

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🔄 Default Behavior (Recommended)

For PR-based and commit-based agents, the default behavior is:

• Generate tests only for public methods that were added or changed
• Ignore unchanged methods, even if they are below coverage

This keeps test generation:

• Focused on the current change
• Faster and more predictable
• Aligned with typical CI workflows

This behavior is enabled by default.

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⚙️ Configuration Options

You can control this behavior using either a CLI flag or an environment variable.

CLI Flag

--changed-methods-only true | false

Environment Variable

export CHANGED_METHODS_ONLY=true | false

Both options are equivalent.

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🧪 Behavior Matrix

Mode	What Gets Tested
true (default)	Public methods that were added or changed and are below coverage
false	All public methods below coverage, regardless of recent changes

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🔧 When to Set false

You may want to disable changed-only filtering when:

• Running repository-wide cleanup or refactoring
• Backfilling tests for legacy code
• Running scheduled or one-off coverage improvement jobs
• Running PR or commit flows where you want broader test generation

In these cases, Early will generate tests for all eligible public methods, not just recently modified ones.

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🧪 Example: GitHub Actions

env:
  CHANGED_METHODS_ONLY: "false"

This forces test generation for all public methods below coverage.

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🧪 Example: Jenkins

environment {
  CHANGED_METHODS_ONLY = 'false'
}

Or inline before running the CLI:

export CHANGED_METHODS_ONLY=false
early generate-pr   # or early generate-commit

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📌 Notes

• This setting applies only after coverage and visibility filtering.
• It does not affect how coverage is calculated.
• For PR and commit agents, true is strongly recommended for day-to-day usage.
• This setting applies only to PR and commit-based agents.
• It is ignored by repository-wide agents such as generate-for-project.

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✅ Summary

Setting	Default	Effect
--changed-methods-only	true	Limit test generation to changed public methods
CHANGED_METHODS_ONLY	true	Environment-based equivalent
Applies to	PR / Commit agents	Controls method selection scope

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This option allows you to balance signal vs. coverage, depending on whether your goal is incremental validation or broad test generation.