Summary

• Add --changed-files-path CLI flag and BUILDKITE_CHANGED_FILES_PATH environment variable
• When provided, the agent reads changed files from the specified file instead of running git commands
• File format is newline-separated list of file paths

Motivation

This is useful when:

• Working with shallow clones where git history is limited
• Using external monorepo tools (Bazel, Nx, Turborepo) that have their own change detection
• CI systems that already compute changed files upstream
• Non-git repositories

Usage

# Via CLI flag
buildkite-agent pipeline upload --changed-files-path /path/to/changed-files.txt

# Via environment variable
BUILDKITE_CHANGED_FILES_PATH=/path/to/changed-files.txt buildkite-agent pipeline upload

File format:

src/main.go
pkg/feature/handler.go
README.md

Test plan

• Added unit tests for readChangedFilesFromPath function
• Added integration test for ifChangedApplicator with changedFilesPath
• Verified existing if_changed tests still pass

🤖 Generated with Claude Code