refactor: split logic into src/api.js, keep run() in index.js

Move all reusable functions (getConfig, getPRDetails, enqueue,
isMergeQueueEnabled, checkEligibility, processPR, getPRNumbers)
into src/api.js. src/index.js retains run() and the entry point
invocation. Also adds the branch input to action.yml, README, and
test coverage.

Author: waheedahmed

README.md

@@ -50,6 +50,15 @@ jobs:
 
 Then add the `enqueue-pullrequest` label to any PR you want automatically enqueued once it's ready.
 
+To process only PRs from a specific branch (useful for `schedule` or `workflow_dispatch` triggers), set `branch`:
+
+```yaml
+      - uses: waheedahmed/enqueue-pullrequest@v1
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          branch: "feature/my-branch"
+```
+
 To enqueue **all** open PRs without requiring a label, set `label` to an empty string:
 
 ```yaml
@@ -66,6 +75,7 @@ To enqueue **all** open PRs without requiring a label, set `label` to an empty s
 |-------|-------------|---------|
 | `github-token` | Token for GitHub API access. Needs `pull-requests: write`. | `${{ github.token }}` |
 | `label` | Label that triggers enqueuing. Set to `""` to process every open PR regardless of labels. | `enqueue-pullrequest` |
+| `branch` | Head branch name to filter PRs by for broad events (`schedule`, `workflow_dispatch`, `push`, etc.). Leave empty to process all open PRs. | `""` |
 | `skip-labels` | Comma-separated blocking labels (e.g. `wip,do-not-merge`). | `""` |
 | `base-branches` | Comma-separated list of allowed base branches. Empty = all branches. | `""` |
 | `skip-drafts` | Skip draft pull requests. | `true` |

action.yml

@@ -19,6 +19,15 @@ inputs:
     required: false
     default: "enqueue-pullrequest"
 
+  branch:
+    description: >
+      Head branch name used to filter pull requests for broad events
+      (schedule, workflow_dispatch, push, etc.). When provided only PRs whose
+      head branch matches this value are processed. Leave empty to process all
+      open PRs.
+    required: false
+    default: ""
+
   skip-labels:
     description: >
       Comma-separated list of labels that prevent a PR from being added to the

src/__tests__/index.test.js

@@ -45,6 +45,7 @@ describe("enqueue-pullrequest action", () => {
     const defaults = {
       "github-token": "ghs_test",
       "label": "enqueue-pullrequest",
+      "branch": "",
       "skip-labels": "",
       "base-branches": "",
       "skip-drafts": "true",
@@ -410,9 +411,10 @@ describe("enqueue-pullrequest action", () => {
 
       await runAction();
 
+      // no head filter — scans all open PRs
       expect(mockOctokit.paginate).toHaveBeenCalledWith(
         mockOctokit.rest.pulls.list,
-        expect.objectContaining({ state: "open" })
+        expect.not.objectContaining({ head: expect.anything() })
       );
       expect(mockOctokit.graphql).toHaveBeenCalledTimes(6);
     });
@@ -433,6 +435,27 @@ describe("enqueue-pullrequest action", () => {
       expect(core.setFailed).not.toHaveBeenCalled();
     });
 
+    test("branch input filters PRs by head branch for broad events", async () => {
+      setupInputs({ branch: "feature/my-branch" });
+      github.context = {
+        eventName: "workflow_dispatch",
+        payload: {},
+        repo: { owner: "acme", repo: "my-repo" },
+      };
+      mockOctokit.paginate.mockResolvedValue([{ number: 42 }]);
+      mockOctokit.graphql
+        .mockResolvedValueOnce({ repository: { pullRequest: makePRPayload() } })
+        .mockResolvedValueOnce(mqEnabled)
+        .mockResolvedValueOnce(mockEnqueue());
+
+      await runAction();
+
+      expect(mockOctokit.paginate).toHaveBeenCalledWith(
+        mockOctokit.rest.pulls.list,
+        expect.objectContaining({ head: "acme:feature/my-branch" })
+      );
+    });
+
     test("pull_request event with missing PR number logs warning", async () => {
       setupInputs();
       github.context = {

src/api.js

@@ -0,0 +1,262 @@
+"use strict";
+
+const core = require("@actions/core");
+
+// ─── Configuration ────────────────────────────────────────────────────────────
+
+function getConfig() {
+  return {
+    token: core.getInput("github-token", { required: true }),
+    label: core.getInput("label").trim(),
+    branch: core.getInput("branch").trim(),
+    skipLabels: core
+      .getInput("skip-labels")
+      .split(",")
+      .map((l) => l.trim())
+      .filter(Boolean),
+    baseBranches: core
+      .getInput("base-branches")
+      .split(",")
+      .map((b) => b.trim())
+      .filter(Boolean),
+    skipDrafts: core.getInput("skip-drafts") !== "false",
+    requiredApprovals: parseInt(core.getInput("required-approvals"), 10) || 0,
+  };
+}
+
+// ─── GitHub GraphQL helpers ───────────────────────────────────────────────────
+
+/** Returns the GraphQL node ID and current merge-queue state for a PR. */
+async function getPRDetails(octokit, owner, repo, prNumber) {
+  const { repository } = await octokit.graphql(
+    `
+    query PRDetails($owner: String!, $repo: String!, $number: Int!) {
+      repository(owner: $owner, name: $repo) {
+        pullRequest(number: $number) {
+          id
+          isDraft
+          state
+          title
+          baseRefName
+          labels(first: 20) {
+            nodes { name }
+          }
+          reviews(states: [APPROVED], last: 10) {
+            totalCount
+          }
+          mergeQueueEntry {
+            id
+            state
+            position
+          }
+        }
+      }
+    }
+    `,
+    { owner, repo, number: prNumber }
+  );
+  return repository?.pullRequest ?? null;
+}
+
+/** Adds a PR (by GraphQL node ID) to the merge queue. */
+async function enqueue(octokit, prNodeId) {
+  const result = await octokit.graphql(
+    `
+    mutation Enqueue($prId: ID!) {
+      enqueuePullRequest(input: { pullRequestId: $prId }) {
+        mergeQueueEntry {
+          id
+          state
+          position
+        }
+      }
+    }
+    `,
+    { prId: prNodeId }
+  );
+  return result.enqueuePullRequest?.mergeQueueEntry ?? null;
+}
+
+/** Returns true if the merge queue is enabled for the given branch. */
+async function isMergeQueueEnabled(octokit, owner, repo, branch) {
+  const { repository } = await octokit.graphql(
+    `
+    query MergeQueueEnabled($owner: String!, $repo: String!, $branch: String!) {
+      repository(owner: $owner, name: $repo) {
+        mergeQueue(branch: $branch) {
+          id
+        }
+      }
+    }
+    `,
+    { owner, repo, branch }
+  );
+  return repository?.mergeQueue != null;
+}
+
+// ─── Eligibility checks ───────────────────────────────────────────────────────
+
+/**
+ * Returns `{ eligible: true }` or `{ eligible: false, reason: string }`.
+ * Uses data already fetched via GraphQL to avoid extra round-trips.
+ */
+function checkEligibility(pr, config) {
+  if (pr.state !== "OPEN") {
+    return { eligible: false, reason: `PR is ${pr.state.toLowerCase()}` };
+  }
+
+  if (config.skipDrafts && pr.isDraft) {
+    return { eligible: false, reason: "PR is a draft" };
+  }
+
+  const labels = pr.labels.nodes.map((l) => l.name);
+
+  if (config.label && !labels.includes(config.label)) {
+    return {
+      eligible: false,
+      reason: `Missing required label "${config.label}"`,
+    };
+  }
+
+  for (const skip of config.skipLabels) {
+    if (labels.includes(skip)) {
+      return { eligible: false, reason: `Has blocking label "${skip}"` };
+    }
+  }
+
+  if (
+    config.baseBranches.length > 0 &&
+    !config.baseBranches.includes(pr.baseRefName)
+  ) {
+    return {
+      eligible: false,
+      reason: `Base branch "${pr.baseRefName}" not in allowed list`,
+    };
+  }
+
+  if (config.requiredApprovals > 0) {
+    const approvals = pr.reviews?.totalCount ?? 0;
+    if (approvals < config.requiredApprovals) {
+      return {
+        eligible: false,
+        reason: `Insufficient approvals: ${approvals}/${config.requiredApprovals}`,
+      };
+    }
+  }
+
+  if (pr.mergeQueueEntry) {
+    return {
+      eligible: false,
+      reason: `Already in merge queue (position ${pr.mergeQueueEntry.position}, state ${pr.mergeQueueEntry.state})`,
+    };
+  }
+
+  return { eligible: true };
+}
+
+// ─── Per-PR processing ────────────────────────────────────────────────────────
+
+async function processPR(octokit, owner, repo, prNumber, config) {
+  core.info(`\n── PR #${prNumber} ──`);
+
+  let pr;
+  try {
+    pr = await getPRDetails(octokit, owner, repo, prNumber);
+  } catch (err) {
+    core.warning(`Could not fetch details for PR #${prNumber}: ${err.message}`);
+    return;
+  }
+
+  if (!pr) {
+    core.warning(`PR #${prNumber} not found`);
+    return;
+  }
+
+  core.info(`Title: ${pr.title}`);
+  core.info(`Base:  ${pr.baseRefName}`);
+
+  const { eligible, reason } = checkEligibility(pr, config);
+
+  if (!eligible) {
+    core.info(`Skipping: ${reason}`);
+    return;
+  }
+
+  core.info("Eligible — checking merge queue is enabled…");
+
+  const mqEnabled = await isMergeQueueEnabled(octokit, owner, repo, pr.baseRefName);
+  if (!mqEnabled) {
+    core.setFailed(
+      `Merge queue is not enabled for branch "${pr.baseRefName}". Enable it under Settings → Branches → branch protection rules.`
+    );
+    return;
+  }
+
+  core.info("Adding to merge queue…");
+
+  try {
+    const entry = await enqueue(octokit, pr.id);
+    if (entry) {
+      core.info(
+        `Added to merge queue: position=${entry.position}, state=${entry.state}`
+      );
+    } else {
+      core.info("Added to merge queue (no entry details returned)");
+    }
+  } catch (err) {
+    core.setFailed(`Failed to enqueue PR #${prNumber}: ${err.message}`);
+  }
+}
+
+// ─── Event routing ────────────────────────────────────────────────────────────
+
+/**
+ * Returns the list of PR numbers to inspect for the current event.
+ * For events that carry a specific PR we use only that one; for broader events
+ * (schedule, workflow_dispatch, push, etc.) we list open PRs, optionally
+ * filtered to a specific head branch via the `branch` input.
+ */
+async function getPRNumbers(octokit, owner, repo, context, config) {
+  const { eventName, payload } = context;
+
+  // Events that identify a single PR directly
+  const singlePREvents = new Set([
+    "pull_request",
+    "pull_request_target",
+    "pull_request_review",
+    "pull_request_review_comment",
+  ]);
+
+  if (singlePREvents.has(eventName)) {
+    const number = payload.pull_request?.number;
+    if (!number) {
+      core.warning(`Event ${eventName} carried no pull_request number`);
+      return [];
+    }
+    return [number];
+  }
+
+  // For check_run / check_suite the PR list is embedded in the payload
+  if (eventName === "check_run") {
+    return (payload.check_run?.pull_requests ?? []).map((pr) => pr.number);
+  }
+
+  if (eventName === "check_suite") {
+    return (payload.check_suite?.pull_requests ?? []).map((pr) => pr.number);
+  }
+
+  // For all other events use the branch input to narrow the search when provided.
+  const listParams = { owner, repo, state: "open", per_page: 100 };
+
+  if (config.branch) {
+    core.info(`Fetching open PRs with head branch "${config.branch}"`);
+    listParams.head = `${owner}:${config.branch}`;
+  } else {
+    core.info(`Scanning all open pull requests in ${owner}/${repo}`);
+  }
+
+  const prs = await octokit.paginate(octokit.rest.pulls.list, listParams);
+  return prs.map((pr) => pr.number);
+}
+
+module.exports = { getConfig, getPRNumbers, processPR };