chore(ci): Improve bot script (#4430)

- It will now rebase another PR if there's a merge conflict.
 - It does not update the base branch if it's already up-to-date.

.github/workflows/bot.yml

@@ -1,9 +1,11 @@
-name: SWC Bot
+name: Bot
 
 on:
   push:
     branches:
       - main
+  schedule:
+    - cron: "0 */1 * * *"
 
 env:
   GIT_COMMITTER_NAME: "SWC Bot"
@@ -40,6 +42,7 @@ jobs:
     name: Create cargo bump commit
     runs-on: ubuntu-latest
     concurrency: swc-bot-cargo-bump
+    if: ${{ github.event_name == 'push' }}
     steps:
       - uses: actions/checkout@v2
         with:

scripts/bot/src/auto-rebase.ts

@@ -38,34 +38,51 @@ function sleep(ms: number) {
         return;
     }
 
-    const pr = autoMergePrs[0];
+    for (const pr of autoMergePrs) {
+        try {
+            const baseBranch = await octokit.rest.repos.getBranch({
+                owner,
+                repo,
+                branch: pr.base.ref
+            });
+            if (baseBranch.data.commit.sha === pr.base.sha) {
+                console.error(`PR #${pr.number} is already up-to-date`);
+                continue
+            }
 
 
+            await octokit.rest.pulls.updateBranch({
+                owner,
+                repo,
+                pull_number: pr.number,
+                expected_head_sha: pr.head.sha
+            });
 
-    await octokit.rest.pulls.updateBranch({
+            console.log(`Updated PR ${pr.number} to merge upstream`);
-        owner,
-        repo,
-        pull_number: pr.number,
-        expected_head_sha: pr.head.sha
-    });
 
-    console.log(`Updated PR ${pr.number} to merge upstream`);
+            await sleep(3000);
 
-    await sleep(3000);
+            const review = await octokit.pulls.createReview({
+                owner,
+                repo,
+                pull_number: pr.number,
+            });
+            console.log(`Created a review on PR ${pr.number}`);
+
+            await octokit.pulls.submitReview({
+                owner,
+                repo,
+                pull_number: pr.number,
+                review_id: review.data.id,
+                event: 'COMMENT',
+                body: 'Automated review comment generated by auto-rebase script',
+            });
+
+            break;
+        } catch (e) {
+            console.error(`Failed to auto-rebase:`, e)
+        }
+    }
 
-    const review = await octokit.pulls.createReview({
-        owner,
-        repo,
-        pull_number: pr.number,
-    });
-    console.log(`Created a review on PR ${pr.number}`);
 
-    await octokit.pulls.submitReview({
-        owner,
-        repo,
-        pull_number: pr.number,
-        review_id: review.data.id,
-        event: 'COMMENT',
-        body: 'Automated review comment generated by auto-rebase script',
-    });
 })()