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Skip file distribution when only version metadata changed.

Version Noise

Release automation creates PRs for version-only changes across 40+ repos. Filter them out before creating PR fatigue.

This implements the volatile field exclusion technique for GitHub Actions workflows.

The Problem

Release automation updates version numbers in distributed files:

  1. Release-please bumps version: 2.5.4 → version: 2.5.5 in CONFIG.md
  2. File distribution workflow detects "file changed"
  3. Creates PRs across 40+ repositories
  4. Every PR contains only a version number change

Result: PR fatigue. Developers ignore automated PRs.

Implementation

Change Detection Script

#!/bin/bash
# scripts/check-changes.sh

strip_version() {
  sed '/^version:.*# x-release-please-version$/d' "$1"
}

# Quick check: any changes at all?
if [ -z "$(git status --porcelain)" ]; then
  echo "has_changes=false" >> "$GITHUB_OUTPUT"
  exit 0
fi

# Changes detected - check if meaningful
if [ -f "CONTRIBUTING.md" ]; then
  SOURCE_CONTENT=$(strip_version "CONTRIBUTING.md")

  if git show HEAD:CONTRIBUTING.md > /dev/null 2>&1; then
    ORIGINAL_CONTENT=$(git show HEAD:CONTRIBUTING.md | \
      sed '/^version:.*# x-release-please-version$/d')

    if [ "$SOURCE_CONTENT" = "$ORIGINAL_CONTENT" ]; then
      git checkout -- CONTRIBUTING.md
      echo "has_changes=false" >> "$GITHUB_OUTPUT"
      exit 0
    fi
  fi
fi

echo "has_changes=true" >> "$GITHUB_OUTPUT"

Workflow Integration

- name: Copy file to target
  run: cp SOURCE.md target-repo/SOURCE.md

- name: Check for meaningful changes
  id: check-changes
  working-directory: target-repo
  run: ${{ github.workspace }}/scripts/check-changes.sh

- name: Commit and push
  if: steps.check-changes.outputs.has_changes == 'true'
  working-directory: target-repo
  run: |
    git add .
    git commit -m "chore: update SOURCE.md"
    git push

Version Line Format

The script expects release-please version annotations:

---
title: Contributing Guidelines
version: 2.5.5 # x-release-please-version
---

The sed pattern must match exactly:

sed '/^version:.*# x-release-please-version$/d'

Edge Cases

Scenario Behavior
No changes at all Skip immediately
Version-only change Strip, compare, skip
Content + version change Distribute (real changes)
File missing in target Distribute (new file)

Extending for Multiple Fields

Strip additional volatile fields:

strip_volatile() {
  sed -e '/^version:.*# x-release-please-version$/d' \
      -e '/^updated:.*$/d' \
      -e '/^generated:.*$/d' \
      "$1"
}

For JSON/YAML files, see the engineering pattern for jq/yq examples.

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