feat(platform/azure): implement automergeStrategy for Azure DevOps platform

lib/config/options/index.ts

@@ -1828,7 +1828,7 @@ const options: RenovateOptions[] = [
     type: 'string',
     allowedValues: ['auto', 'fast-forward', 'merge-commit', 'rebase', 'squash'],
     default: 'auto',
-    supportedPlatforms: ['bitbucket', 'gitea'],
+    supportedPlatforms: ['azure', 'bitbucket', 'gitea'],
   },
   {
     name: 'automergeComment',

lib/modules/platform/azure/__snapshots__/index.spec.ts.snap

@@ -49,6 +49,118 @@ exports[`modules/platform/azure/index createPr() should create and return an app
 }
 `;
 
+exports[`modules/platform/azure/index createPr() when usePlatformAutomerge is set should create PR with automergeStrategy fast-forward 1`] = `
+{
+  "autoCompleteSetBy": {
+    "id": "123",
+  },
+  "bodyStruct": {
+    "hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  },
+  "completionOptions": {
+    "deleteSourceBranch": true,
+    "mergeCommitMessage": "The Title",
+    "mergeStrategy": 3,
+    "squashMerge": false,
+  },
+  "createdAt": undefined,
+  "createdBy": {
+    "id": "123",
+  },
+  "number": 456,
+  "pullRequestId": 456,
+  "sourceBranch": undefined,
+  "sourceRefName": undefined,
+  "state": "open",
+  "targetBranch": undefined,
+  "title": "The Title",
+}
+`;
+
+exports[`modules/platform/azure/index createPr() when usePlatformAutomerge is set should create PR with automergeStrategy merge-commit 1`] = `
+{
+  "autoCompleteSetBy": {
+    "id": "123",
+  },
+  "bodyStruct": {
+    "hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  },
+  "completionOptions": {
+    "deleteSourceBranch": true,
+    "mergeCommitMessage": "The Title",
+    "mergeStrategy": 1,
+    "squashMerge": false,
+  },
+  "createdAt": undefined,
+  "createdBy": {
+    "id": "123",
+  },
+  "number": 456,
+  "pullRequestId": 456,
+  "sourceBranch": undefined,
+  "sourceRefName": undefined,
+  "state": "open",
+  "targetBranch": undefined,
+  "title": "The Title",
+}
+`;
+
+exports[`modules/platform/azure/index createPr() when usePlatformAutomerge is set should create PR with automergeStrategy rebase 1`] = `
+{
+  "autoCompleteSetBy": {
+    "id": "123",
+  },
+  "bodyStruct": {
+    "hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  },
+  "completionOptions": {
+    "deleteSourceBranch": true,
+    "mergeCommitMessage": "The Title",
+    "mergeStrategy": 3,
+    "squashMerge": false,
+  },
+  "createdAt": undefined,
+  "createdBy": {
+    "id": "123",
+  },
+  "number": 456,
+  "pullRequestId": 456,
+  "sourceBranch": undefined,
+  "sourceRefName": undefined,
+  "state": "open",
+  "targetBranch": undefined,
+  "title": "The Title",
+}
+`;
+
+exports[`modules/platform/azure/index createPr() when usePlatformAutomerge is set should create PR with automergeStrategy squash 1`] = `
+{
+  "autoCompleteSetBy": {
+    "id": "123",
+  },
+  "bodyStruct": {
+    "hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+  },
+  "completionOptions": {
+    "deleteSourceBranch": true,
+    "mergeCommitMessage": "The Title",
+    "mergeStrategy": 2,
+    "squashMerge": false,
+  },
+  "createdAt": undefined,
+  "createdBy": {
+    "id": "123",
+  },
+  "number": 456,
+  "pullRequestId": 456,
+  "sourceBranch": undefined,
+  "sourceRefName": undefined,
+  "state": "open",
+  "targetBranch": undefined,
+  "title": "The Title",
+}
+`;
+
 exports[`modules/platform/azure/index createPr() when usePlatformAutomerge is set should create and return a PR object with auto-complete set 1`] = `
 {
   "autoCompleteSetBy": {

lib/modules/platform/azure/index.spec.ts

@@ -936,7 +936,7 @@ describe('modules/platform/azure/index', () => {
         expect(pr).toMatchSnapshot();
       });
 
-      it('should only call getMergeMethod once per run', async () => {
+      it('should only call getMergeMethod once per run when automergeStrategy is auto', async () => {
         await initRepo({ repository: 'some/repo' });
         const prResult = [
           {
@@ -1001,7 +1001,10 @@ describe('modules/platform/azure/index', () => {
           prTitle: 'The Title',
           prBody: 'Hello world',
           labels: ['deps', 'renovate'],
-          platformOptions: { usePlatformAutomerge: true },
+          platformOptions: {
+            automergeStrategy: 'auto',
+            usePlatformAutomerge: true,
+          },
         });
 
         await azure.createPr({
@@ -1010,12 +1013,125 @@ describe('modules/platform/azure/index', () => {
           prTitle: 'The Second Title',
           prBody: 'Hello world',
           labels: ['deps', 'renovate'],
-          platformOptions: { usePlatformAutomerge: true },
+          platformOptions: {
+            automergeStrategy: 'auto',
+            usePlatformAutomerge: true,
+          },
         });
 
         expect(updateFn).toHaveBeenCalledTimes(2);
         expect(azureHelper.getMergeMethod).toHaveBeenCalledTimes(1);
       });
+
+      it.each`
+        automergeStrategy
+        ${'fast-forward'}
+        ${'merge-commit'}
+        ${'rebase'}
+        ${'squash'}
+      `(
+        'should not call getMergeMethod when automergeStrategy is $automergeStrategy',
+        async (automergeStrategy) => {
+          await initRepo({ repository: 'some/repo' });
+          const prResult = {
+            pullRequestId: 123,
+            title: 'The Title',
+            createdBy: {
+              id: '123',
+            },
+          };
+          const prUpdateResults = {
+            ...prResult,
+            autoCompleteSetBy: {
+              id: prResult.createdBy.id,
+            },
+            completionOptions: {
+              squashMerge: true,
+              deleteSourceBranch: true,
+              mergeCommitMessage: 'The Title',
+            },
+          };
+          const updateFn = jest.fn(() => Promise.resolve(prUpdateResults));
+
+          azureApi.gitApi.mockResolvedValue(
+            partial<IGitApi>({
+              createPullRequest: jest.fn(() => Promise.resolve(prResult)),
+              createPullRequestLabel: jest.fn().mockResolvedValue({}),
+              updatePullRequest: updateFn,
+            }),
+          );
+          await azure.createPr({
+            sourceBranch: 'some-branch',
+            targetBranch: 'dev',
+            prTitle: 'The Title',
+            prBody: 'Hello world',
+            labels: ['deps', 'renovate'],
+            platformOptions: {
+              automergeStrategy,
+              usePlatformAutomerge: true,
+            },
+          });
+
+          expect(azureHelper.getMergeMethod).toHaveBeenCalledTimes(0);
+        },
+      );
+
+      it.each`
+        automergeStrategy | prMergeStrategy
+        ${'fast-forward'} | ${GitPullRequestMergeStrategy.Rebase}
+        ${'merge-commit'} | ${GitPullRequestMergeStrategy.NoFastForward}
+        ${'rebase'}       | ${GitPullRequestMergeStrategy.Rebase}
+        ${'squash'}       | ${GitPullRequestMergeStrategy.Squash}
+      `(
+        'should create PR with automergeStrategy $automergeStrategy',
+        async ({ automergeStrategy, prMergeStrategy }) => {
+          await initRepo({ repository: 'some/repo' });
+          const prResult = {
+            pullRequestId: 456,
+            title: 'The Title',
+            createdBy: {
+              id: '123',
+            },
+          };
+          const prUpdateResult = {
+            ...prResult,
+            autoCompleteSetBy: {
+              id: prResult.createdBy.id,
+            },
+            completionOptions: {
+              mergeStrategy: prMergeStrategy,
+              squashMerge: false,
+              deleteSourceBranch: true,
+              mergeCommitMessage: 'The Title',
+            },
+          };
+          const updateFn = jest.fn().mockResolvedValue(prUpdateResult);
+          azureApi.gitApi.mockResolvedValueOnce(
+            partial<IGitApi>({
+              createPullRequest: jest.fn().mockResolvedValue(prResult),
+              createPullRequestLabel: jest.fn().mockResolvedValue({}),
+              updatePullRequest: updateFn,
+            }),
+          );
+          const pr = await azure.createPr({
+            sourceBranch: 'some-branch',
+            targetBranch: 'dev',
+            prTitle: 'The Title',
+            prBody: 'Hello world',
+            labels: ['deps', 'renovate'],
+            platformOptions: {
+              automergeStrategy,
+              usePlatformAutomerge: true,
+            },
+          });
+          expect(pr).toMatchSnapshot();
+          expect(updateFn).toHaveBeenCalled();
+          expect(
+            updateFn.mock.calls[0][0].completionOptions.mergeStrategy,
+          ).toBe(prMergeStrategy);
+          expect(azureHelper.getMergeMethod).toHaveBeenCalledTimes(0);
+        },
+      );
     });
 
     it('should create and return an approved PR object', async () => {

lib/modules/platform/azure/index.ts

@@ -9,6 +9,7 @@ import {
   GitVersionDescriptor,
   PullRequestStatus,
 } from 'azure-devops-node-api/interfaces/GitInterfaces.js';
+import type { MergeStrategy } from '../../../config/types';
 import {
   REPOSITORY_ARCHIVED,
   REPOSITORY_EMPTY,
@@ -461,6 +462,22 @@ async function getMergeStrategy(
   );
 }
 
+function mapMergeStrategy(
+  mergeStrategy?: MergeStrategy,
+): GitPullRequestMergeStrategy {
+  switch (mergeStrategy) {
+    case 'rebase':
+    case 'fast-forward':
+      return GitPullRequestMergeStrategy.Rebase;
+    case 'merge-commit':
+      return GitPullRequestMergeStrategy.NoFastForward;
+    case 'squash':
+      return GitPullRequestMergeStrategy.Squash;
+    default:
+      return GitPullRequestMergeStrategy.NoFastForward;
+  }
+}
+
 export async function createPr({
   sourceBranch,
   targetBranch,
@@ -491,7 +508,10 @@ export async function createPr({
     config.repoId,
   );
   if (platformOptions?.usePlatformAutomerge) {
-    const mergeStrategy = await getMergeStrategy(pr.targetRefName!);
+    const mergeStrategy =
+      platformOptions.automergeStrategy === 'auto'
+        ? await getMergeStrategy(pr.targetRefName!)
+        : mapMergeStrategy(platformOptions.automergeStrategy);
     pr = await azureApiGit.updatePullRequest(
       {
         autoCompleteSetBy: {

lib/modules/platform/azure/readme.md

@@ -18,10 +18,6 @@ Permissions for your PAT should be at minimum:
 
 Remember to set `platform=azure` somewhere in your Renovate config file.
 
-## Features awaiting implementation
-
-- The `automergeStrategy` configuration option has not been implemented for this platform, and all values behave as if the value `auto` was used. Renovate will use the merge strategy configured in the Azure Repos repository itself, and this cannot be overridden yet
-
 ## Running Renovate in Azure Pipelines
 
 ### Setting up a new pipeline

lib/modules/platform/types.ts

@@ -96,6 +96,7 @@ export interface Issue {
 }
 export type PlatformPrOptions = {
   autoApprove?: boolean;
+  automergeStrategy?: MergeStrategy;
   azureWorkItemId?: number;
   bbUseDefaultReviewers?: boolean;
   gitLabIgnoreApprovals?: boolean;

lib/workers/repository/update/pr/index.ts

@@ -55,6 +55,7 @@ export function getPlatformPrOptions(
 
   return {
     autoApprove: !!config.autoApprove,
+    automergeStrategy: config.automergeStrategy,
     azureWorkItemId: config.azureWorkItemId ?? 0,
     bbUseDefaultReviewers: !!config.bbUseDefaultReviewers,
     gitLabIgnoreApprovals: !!config.gitLabIgnoreApprovals,