1 files changed, 54 insertions, 0 deletions
diff --git a/app/services/merge_requests/create_from_issue_service.rb b/app/services/merge_requests/create_from_issue_service.rb
new file mode 100644
index 00000000000..738cedbaed7
--- /dev/null
+++ b/app/services/merge_requests/create_from_issue_service.rb
@@ -0,0 +1,54 @@
+module MergeRequests
+  class CreateFromIssueService < MergeRequests::CreateService
+    def execute
+      return error('Invalid issue iid') unless issue_iid.present? && issue.present?
+
+      result = CreateBranchService.new(project, current_user).execute(branch_name, ref)
+      return result if result[:status] == :error
+
+      SystemNoteService.new_issue_branch(issue, project, current_user, branch_name)
+
+      new_merge_request = create(merge_request)
+
+      if new_merge_request.valid?
+        success(new_merge_request)
+      else
+        error(new_merge_request.errors)
+      end
+    end
+
+    private
+
+    def issue_iid
+      @isssue_iid ||= params.delete(:issue_iid)
+    end
+
+    def issue
+      @issue ||= IssuesFinder.new(current_user, project_id: project.id).find_by(iid: issue_iid)
+    end
+
+    def branch_name
+      @branch_name ||= issue.to_branch_name
+    end
+
+    def ref
+      project.default_branch || 'master'
+    end
+
+    def merge_request
+      MergeRequests::BuildService.new(project, current_user, merge_request_params).execute
+    end
+
+    def merge_request_params
+      {
+        source_project_id: project.id,
+        source_branch: branch_name,
+        target_project_id: project.id
+      }
+    end
+
+    def success(merge_request)
+      super().merge(merge_request: merge_request)
+    end
+  end
+end