Poc runner checkout merge refpoc-runner-checkout-merge-ref

3 files changed, 30 insertions, 2 deletions

diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index b937bef100b..eff4874205e 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -633,6 +633,7 @@ class MergeRequest < ActiveRecord::Base
 
   def create_merge_request_diff
     fetch_ref!
+    create_merge_commit!
 
     # n+1: https://gitlab.com/gitlab-org/gitlab-ce/issues/37435
     Gitlab::GitalyClient.allow_n_plus_1_calls do
@@ -1047,10 +1048,19 @@ class MergeRequest < ActiveRecord::Base
     target_project.repository.fetch_source_branch!(source_project.repository, source_branch, ref_path)
   end
 
+  def create_merge_commit!
+    target_project.repository.create_ref(source_branch, merge_ref_path)
+    target_project.repository.merge_to(user, target_branch_sha, merge_ref_path, 'aaa')
+  end
+
   def ref_path
     "refs/#{Repository::REF_MERGE_REQUEST}/#{iid}/head"
   end
 
+  def merge_ref_path
+    "refs/#{Repository::REF_MERGE_REQUEST}/#{iid}/merge"
+  end
+
   def in_locked_state
     begin
       lock_mr
@@ -1112,6 +1122,9 @@ class MergeRequest < ActiveRecord::Base
       variables.append(key: 'CI_MERGE_REQUEST_REF_PATH',
                        value: ref_path.to_s)
 
+      variables.append(key: 'CI_MERGE_REQUEST_MERGE_REF_PATH',
+                       value: merge_ref_path.to_s)
+
       variables.append(key: 'CI_MERGE_REQUEST_PROJECT_ID',
                        value: project.id.to_s)
 
diff --git a/app/models/repository.rb b/app/models/repository.rb
index 015a179f374..0a969e8504a 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -837,6 +837,14 @@ class Repository
     end
   end
 
+  def merge_to(user, source_sha, target_branch, message)
+    with_cache_hooks do
+      raw_repository.merge(user, source_sha, target_branch, message) do |commit_id|
+        nil # Return value does not matter.
+      end
+    end
+  end
+
   def ff_merge(user, source, target_branch, merge_request: nil)
     their_commit_id = commit(source)&.id
     raise 'Invalid merge source' if their_commit_id.nil?
diff --git a/lib/api/entities.rb b/lib/api/entities.rb
index 22403664c21..2472eb72b85 100644
--- a/lib/api/entities.rb
+++ b/lib/api/entities.rb
@@ -1312,12 +1312,19 @@ module API
       class GitInfo < Grape::Entity
         expose :repo_url, :ref, :sha, :before_sha
         expose :ref_type do |model|
-          if model.tag
+          if model.pipeline.branch?
+            'branch'
+          elsif model.pipeline.merge_request?
+            'merge-requests'
+          elsif model.pipeline.tag?
             'tag'
           else
-            'branch'
+            raise ArgumentError, 'Invalid ref type!'
           end
         end
+        expose :merge_request_iid, if: ->(job, _) { job.pipeline.merge_request? } do
+          job.pipeline.merge_request.iid
+        end
       end
 
       class RunnerInfo < Grape::Entity