Implement tagging PRs that have conflicts (#3)

Author: MattyTheHacker

src/autoupdater.ts

@@ -450,6 +450,7 @@ export class AutoUpdater {
     const retryCount = this.config.retryCount();
     const retrySleep = this.config.retrySleep();
     const mergeConflictAction = this.config.mergeConflictAction();
+    const mergeConflictLabel = this.config.mergeConflictLabel();
 
     let retries = 0;
 
@@ -489,6 +490,37 @@ export class AutoUpdater {
               // Ignore conflicts if configured to do so.
               ghCore.info('Merge conflict detected, skipping update.');
               return false;
+            } else if (mergeConflictAction === 'label') {
+              ghCore.info(
+                'Merge conflict detected, labelling with label: ' +
+                  mergeConflictLabel,
+              );
+              // Fetch current labels on the PR
+              const { data: prData } = await this.octokit.rest.pulls.get({
+                owner: mergeOpts.owner as string,
+                repo: mergeOpts.repo as string,
+                pull_number: prNumber,
+              });
+              const currentLabels = prData.labels
+                .map((l: any) => l.name)
+                .filter(Boolean);
+              if (!currentLabels.includes(mergeConflictLabel)) {
+                const newLabels = [...currentLabels, mergeConflictLabel];
+                await this.octokit.rest.issues.update({
+                  owner: mergeOpts.owner as string,
+                  repo: mergeOpts.repo as string,
+                  issue_number: prNumber,
+                  labels: newLabels,
+                });
+                ghCore.info(
+                  `Added merge conflict label '${mergeConflictLabel}' to PR #${prNumber}.`,
+                );
+              } else {
+                ghCore.info(
+                  `Merge conflict label '${mergeConflictLabel}' already present on PR #${prNumber}.`,
+                );
+              }
+              return false;
             } else {
               // Else, throw an error so we don't continue retrying.
               ghCore.error('Merge conflict error trying to update branch');

src/config-loader.ts

@@ -61,6 +61,10 @@ export class ConfigLoader {
     return this.getValue('MERGE_CONFLICT_ACTION', false, 'fail');
   }
 
+  mergeConflictLabel(): string {
+    return this.getValue('MERGE_CONFLICT_LABEL', false, 'merge-conflict');
+  }
+
   githubRef(): string {
     return this.getValue('GITHUB_REF', true, '');
   }

test/autoupdate.test.ts

@@ -16,6 +16,7 @@ import {
   WorkflowDispatchEvent,
   WorkflowRunEvent,
 } from '@octokit/webhooks-types/schema';
+import * as core from '@actions/core';
 
 type PullRequestResponse =
   Endpoints['GET /repos/{owner}/{repo}/pulls/{pull_number}']['response'];
@@ -1323,4 +1324,87 @@ describe('test `merge`', () => {
       expect(scope.isDone()).toBe(true);
     }
   });
+
+  test('merge conflict label is configured and merge conflict label is already present', async () => {
+    (config.retryCount as jest.Mock).mockReturnValue(0);
+    (config.mergeConflictAction as jest.Mock).mockReturnValue('label');
+    (config.mergeConflictLabel as jest.Mock).mockReturnValue('merge-conflict');
+    const updater = new AutoUpdater(config, emptyEvent);
+
+    // Mock the PR labels to already include the merge conflict label
+    const prNumber = 1;
+    const existingLabels = [
+      { id: 1, name: 'bug' },
+      { id: 2, name: 'merge-conflict' },
+    ];
+
+    // nock for merge attempt (409 merge conflict)
+    const mergeScope = nock('https://api.github.com:443')
+      .post(`/repos/${owner}/${repo}/merges`, {
+        commit_message: mergeOpts.commit_message,
+        base: mergeOpts.base,
+        head: mergeOpts.head,
+      })
+      .reply(409, { message: 'Merge conflict' });
+
+    const getScope = nock('https://api.github.com:443')
+      .get(`/repos/${owner}/${repo}/pulls/${prNumber}`)
+      .reply(200, { labels: existingLabels });
+
+    const updateScope = nock('https://api.github.com:443')
+      .patch(`/repos/${owner}/${repo}/issues/${prNumber}`)
+      .reply(200, {});
+
+    const setOutput = jest.fn();
+    const infoSpy = jest.spyOn(core, 'info');
+
+    await updater.merge(owner, prNumber, mergeOpts, setOutput);
+
+    expect(mergeScope.isDone()).toBe(true);
+    expect(getScope.isDone()).toBe(true);
+    expect(updateScope.isDone()).toBe(false);
+    expect(infoSpy).toHaveBeenCalledWith(
+      expect.stringContaining('already present'),
+    );
+  });
+
+  test('merge conflict label is configured and merge conflict label is not present', async () => {
+    (config.retryCount as jest.Mock).mockReturnValue(0);
+    (config.mergeConflictAction as jest.Mock).mockReturnValue('label');
+    (config.mergeConflictLabel as jest.Mock).mockReturnValue('merge-conflict');
+    const updater = new AutoUpdater(config, emptyEvent);
+
+    // Mock the PR labels to already include the merge conflict label
+    const prNumber = 1;
+    const existingLabels = [{ id: 1, name: 'bug' }];
+
+    // nock for merge attempt (409 merge conflict)
+    const mergeScope = nock('https://api.github.com:443')
+      .post(`/repos/${owner}/${repo}/merges`, {
+        commit_message: mergeOpts.commit_message,
+        base: mergeOpts.base,
+        head: mergeOpts.head,
+      })
+      .reply(409, { message: 'Merge conflict' });
+
+    const getScope = nock('https://api.github.com:443')
+      .get(`/repos/${owner}/${repo}/pulls/${prNumber}`)
+      .reply(200, { labels: existingLabels });
+
+    const updateScope = nock('https://api.github.com:443')
+      .patch(`/repos/${owner}/${repo}/issues/${prNumber}`)
+      .reply(200, {});
+
+    const setOutput = jest.fn();
+    const infoSpy = jest.spyOn(core, 'info');
+
+    await updater.merge(owner, prNumber, mergeOpts, setOutput);
+
+    expect(mergeScope.isDone()).toBe(true);
+    expect(getScope.isDone()).toBe(true);
+    expect(updateScope.isDone()).toBe(false);
+    expect(infoSpy).toHaveBeenCalledWith(
+      expect.stringContaining('Added merge conflict label'),
+    );
+  });
 });

test/config-loader.test.ts

@@ -71,6 +71,13 @@ const tests = [
     default: 'fail',
     type: 'string',
   },
+  {
+    name: 'mergeConflictLabel',
+    envVar: 'MERGE_CONFLICT_LABEL',
+    required: false,
+    default: 'merge-conflict',
+    type: 'string',
+  },
   {
     name: 'githubRef',
     envVar: 'GITHUB_REF',