Calculate the Percentage of New Code

# -*- mode: yaml -*-

manifest:
  version: 1.0

automations:
  percent_new_code:
    if:
      - true
    run: 
      - action: add-comment@v1
        args:
          comment: |
            This PR is {{ changes.ratio }}% new code.

changes:
  # Sum all the lines added/edited in the PR
  additions: {{ branch.diff.files_metadata | map(attr='additions') | sum }}
  # Sum all the line removed in the PR
  deletions: {{ branch.diff.files_metadata | map(attr='deletions') | sum }}
  # Calculate the ratio of new code
  ratio: {{ (changes.additions / (changes.additions + changes.deletions)) * 100 | round(2) }}