From 4b2adf4cb2bb217f6105b0cf36a5d52e80e702aa Mon Sep 17 00:00:00 2001
From: Sara Tan <saratan@mac.com>
Date: Tue, 5 Oct 2021 16:50:15 -0700
Subject: [PATCH 1/2] Continue if comparing commits returns an error

---
 src/autoupdater.ts      | 33 +++++++++++++++++++++------------
 test/autoupdate.test.ts | 15 +++++++++++++++
 2 files changed, 36 insertions(+), 12 deletions(-)

diff --git a/src/autoupdater.ts b/src/autoupdater.ts
index 0a1bd85c..9c484b81 100644
--- a/src/autoupdater.ts
+++ b/src/autoupdater.ts
@@ -172,6 +172,7 @@ export class AutoUpdater {
   }
 
   async update(sourceEventOwner: string, pull: PullRequest): Promise<boolean> {
+    console.log('Updating...............');
     const { ref } = pull.head;
     ghCore.info(`Evaluating pull request #${pull.number}...`);
 
@@ -227,6 +228,7 @@ export class AutoUpdater {
   }
 
   async prNeedsUpdate(pull: PullRequest): Promise<boolean> {
+    console.log('Checking if PR needs update');
     if (pull.merged === true) {
       ghCore.warning('Skipping pull request, already merged.');
       return false;
@@ -244,18 +246,25 @@ export class AutoUpdater {
       return false;
     }
 
-    const { data: comparison } = await this.octokit.rest.repos.compareCommits({
-      owner: pull.head.repo.owner.login,
-      repo: pull.head.repo.name,
-      // This base->head, head->base logic is intentional, we want
-      // to see what would happen if we merged the base into head not
-      // vice-versa.
-      base: pull.head.label,
-      head: pull.base.label,
-    });
-
-    if (comparison.behind_by === 0) {
-      ghCore.info('Skipping pull request, up-to-date with base branch.');
+    try {
+      const { data: comparison } =
+        await this.octokit.rest.repos.compareCommitsWithBasehead({
+          owner: pull.head.repo.owner.login,
+          repo: pull.head.repo.name,
+          // This base->head, head->base logic is intentional, we want
+          // to see what would happen if we merged the base into head not
+          // vice-versa. This parameter expects the format {base}...{head}.
+          basehead: `${pull.head.label}...${pull.base.label}`,
+        });
+
+      if (comparison.behind_by === 0) {
+        ghCore.info('Skipping pull request, up-to-date with base branch.');
+        return false;
+      }
+    } catch (e: unknown) {
+      if (e instanceof Error) {
+        `Caught error trying to evaluate PR: ${e.message}`;
+      }
       return false;
     }
 
diff --git a/test/autoupdate.test.ts b/test/autoupdate.test.ts
index bc68072b..1259b962 100644
--- a/test/autoupdate.test.ts
+++ b/test/autoupdate.test.ts
@@ -1038,6 +1038,21 @@ describe('test `merge`', () => {
     }
   });
 
+  test('handles errors from compareCommitsWithBasehead', async () => {
+    (config.retryCount as jest.Mock).mockReturnValue(0);
+    const updater = new AutoUpdater(config, emptyEvent);
+
+    const scope = nock('https://api.github.com:443')
+      .get(`/repos/${owner}/${repo}/compare/${head}...${base}`)
+      .reply(404, {
+        message: 'Not Found',
+      });
+
+    const needsUpdate = await updater.update(owner, <any>validPull);
+    expect(needsUpdate).toEqual(false);
+    expect(scope.isDone()).toEqual(true);
+  });
+
   test('handles fork authorisation errors', async () => {
     (config.retryCount as jest.Mock).mockReturnValue(0);
     const updater = new AutoUpdater(config, emptyEvent);

From 5c560ecd678a348e6b6a87b40fba7b6935483d4f Mon Sep 17 00:00:00 2001
From: Sara Tan <saratan@mac.com>
Date: Tue, 5 Oct 2021 17:01:45 -0700
Subject: [PATCH 2/2] Remove console logs

---
 src/autoupdater.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/autoupdater.ts b/src/autoupdater.ts
index 9c484b81..4ee6c7a0 100644
--- a/src/autoupdater.ts
+++ b/src/autoupdater.ts
@@ -172,7 +172,6 @@ export class AutoUpdater {
   }
 
   async update(sourceEventOwner: string, pull: PullRequest): Promise<boolean> {
-    console.log('Updating...............');
     const { ref } = pull.head;
     ghCore.info(`Evaluating pull request #${pull.number}...`);
 
@@ -228,7 +227,6 @@ export class AutoUpdater {
   }
 
   async prNeedsUpdate(pull: PullRequest): Promise<boolean> {
-    console.log('Checking if PR needs update');
     if (pull.merged === true) {
       ghCore.warning('Skipping pull request, already merged.');
       return false;
@@ -263,7 +261,9 @@ export class AutoUpdater {
       }
     } catch (e: unknown) {
       if (e instanceof Error) {
-        `Caught error trying to evaluate PR: ${e.message}`;
+        ghCore.error(
+          `Caught error trying to compare base with head: ${e.message}`,
+        );
       }
       return false;
     }