Add GitHub Action to add "pull ready" to a PR upon successful checks

Author: michelle-yooh

.github/CODEOWNERS

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+*   @entrpn

.github/workflows/AddPullReady.yml

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+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: Add Pull Ready Label
+
+on:
+  workflow_run:
+    workflows: [Unit Test, Linter]
+    types:
+      - completed
+  pull_request_review:
+  pull_request_review_comment:
+  workflow_dispatch:
+
+jobs:
+  AddPullReady:
+    permissions:
+      checks: read
+      pull-requests: write
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/github-script@v7
+        with:
+          script: |
+            const owner = "google"
+            const repo = "maxdiffusion"
+            let pull_number = -1
+            if (context.payload.pull_request !== undefined) {
+              pull_number = context.payload.pull_request.number
+            } else if (context.payload.workflow_run !== undefined) {
+              if (context.payload.workflow_run.pull_requests.length === 0) {
+                console.log("This workflow is NOT running within a PR's context")
+                process.exit()
+              }
+              console.log(context.payload.workflow_run.pull_requests)
+              pull_number = context.payload.workflow_run.pull_requests[0].number
+            } else {
+              console.log("This workflow is running within an invalid context")
+              process.exit(1)
+            }
+            const reviews = await github.rest.pulls.listReviews({
+              owner,
+              repo,
+              pull_number,
+            })
+            const decision_query = `
+              query($owner: String!, $repo: String!, $pull_number: Int!) {
+                repository(owner: $owner, name: $repo) {
+                  pullRequest(number: $pull_number) {
+                    reviewDecision # Fetches the overall review status
+                  }
+                }
+              }
+            `;
+            const decision_result = await github.graphql(decision_query, { owner, repo, pull_number });
+
+            if (reviews.data.length === 0) {
+              console.log("Not adding pull ready because the PR is not approved yet.")
+              process.exit()
+            }
+            let is_approved = false
+            if (decision_result.repository.pullRequest.reviewDecision === "APPROVED") {
+              is_approved = true
+            }
+            if (!is_approved) {
+              console.log("Not adding pull ready because the PR is not approved yet by sufficient code owners.")
+              process.exit()
+            }
+
+            const commits = await github.rest.pulls.listCommits({
+              owner,
+              repo,
+              pull_number,
+              per_page: 100,
+            })
+            // Check that the number of commits in the PR is 1.
+            if (commits.data.length !== 1) {
+              console.log("Not adding pull ready because the PR has more than one commit. Please squash your commits.")
+              process.exit(1)
+            }
+            const ref = commits.data.slice(-1)[0].sha
+            const checkRuns = await github.rest.checks.listForRef({
+              owner,
+              repo,
+              ref,
+            })
+            if (checkRuns.data.check_runs.length === 0) {
+              console.log("Not adding pull ready because no check runs are associated with the last commit: " + ref)
+              process.exit()
+            }
+            for (const checkRun of checkRuns.data.check_runs) {
+              if (checkRun.name.endsWith(context.job)) continue
+              if (checkRun.conclusion !== "success") {
+                console.log("Not adding pull ready because " + checkRun.name + " has not passed yet: " + checkRun.html_url)
+                process.exit()
+              }
+            }
+            console.log("Adding pull ready label because the PR is approved AND all the check runs have passed")
+            await github.rest.issues.addLabels({
+              issue_number: pull_number,
+              labels: ["pull ready"],
+              owner,
+              repo,
+            })