cozystack/.github/workflows/pr-size.yaml

name: PR size label

on:
  pull_request_target:
    types: [opened, synchronize, reopened]

permissions:
  contents: read
  pull-requests: write

concurrency:
  group: pr-size-${{ github.event.pull_request.number }}
  cancel-in-progress: true

jobs:
  size:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v7
        with:
          script: |
            const pr = context.payload.pull_request;

            // Skip files that should not count as "real diff" — they are produced by tools,
            // not authored by humans, and including them lies to reviewers about review effort:
            //   - vendored Go deps,
            //   - kubebuilder/openapi inline generated files (zz_generated.{deepcopy,conversion,defaults,openapi}.go),
            //   - whole code-generated trees from client-gen / lister-gen / applyconfiguration-gen
            //     and protobuf (any path under a `generated/` directory or ending in `.pb.go`),
            //   - vendored Helm charts,
            //   - lockfiles.
            const isIgnored = (path) =>
              path.startsWith('vendor/') ||
              /\bzz_generated\.[^/]*\.go$/.test(path) ||
              /(^|\/)generated\//.test(path) ||
              path.endsWith('.pb.go') ||
              /^packages\/system\/[^/]+\/charts\//.test(path) ||
              path === 'go.sum' || path.endsWith('/go.sum') ||
              path.endsWith('.lock') || path.endsWith('.lockb');

            const files = await github.paginate(github.rest.pulls.listFiles, {
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: pr.number,
            });
            const lines = files
              .filter((f) => !isIgnored(f.filename))
              .reduce((acc, f) => acc + (f.additions || 0) + (f.deletions || 0), 0);

            // Thresholds match the descriptions of size/* labels in .github/labels.yml.
            const bucket =
              lines <= 9   ? 'XS' :
              lines <= 29  ? 'S'  :
              lines <= 99  ? 'M'  :
              lines <= 499 ? 'L'  :
              lines <= 999 ? 'XL' : 'XXL';
            const target = `size/${bucket}`;

            // Match both legacy "size:" and canonical "size/" during the migration window.
            const existing = (pr.labels || []).map((l) => l.name);
            const oldSizes = existing.filter((n) => n.startsWith('size/') || n.startsWith('size:'));
            const alreadyTarget = oldSizes.includes(target);

            // Remove every size/* label that is not the target. Tolerate 404 — concurrent
            // runs or manual edits between event payload and execution can race here.
            for (const name of oldSizes) {
              if (name === target) continue;
              try {
                await github.rest.issues.removeLabel({
                  owner: context.repo.owner,
                  repo: context.repo.repo,
                  issue_number: pr.number,
                  name,
                });
              } catch (e) {
                if (e.status !== 404) throw e;
                core.info(`label ${name} already gone (404)`);
              }
            }

            if (alreadyTarget && oldSizes.length === 1) {
              core.info(`PR #${pr.number}: ${lines} lines, label already ${target}`);
              return;
            }
            if (!alreadyTarget) {
              await github.rest.issues.addLabels({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: pr.number,
                labels: [target],
              });
            }
            core.info(`PR #${pr.number}: ${lines} lines -> ${target}`);