Expose moved_to in issues api

changelogs/unreleased/expose_moved_to_in_issues_api.yml

+---
+title: Expose moved_to_id in issues API
+merge_request: 20083
+author: Lee Tickett
+type: added

doc/api/issues.md

@@ -113,6 +113,7 @@ Example response:
       "id" : 76,
       "title" : "Consequatur vero maxime deserunt laboriosam est voluptas dolorem.",
       "created_at" : "2016-01-04T15:31:51.081Z",
+      "moved_to_id" : null,
       "iid" : 6,
       "labels" : ["foo", "bar"],
       "upvotes": 4,

lib/api/entities.rb

@@ -660,6 +660,8 @@ module API
       expose :subscribed, if: -> (_, options) { options.fetch(:include_subscribed, true) } do |issue, options|
         issue.subscribed?(options[:current_user], options[:project] || issue.project)
       end
+
+      expose :moved_to_id
     end
 
     class IssuableTimeStats < Grape::Entity

spec/requests/api/issues/get_project_issues_spec.rb

@@ -589,6 +589,24 @@ describe API::Issues do
       expect(json_response['subscribed']).to be_truthy
     end
 
+    context "moved_to_id" do
+      let(:moved_issue) do
+        create(:closed_issue, project: project, moved_to: issue)
+      end
+
+      it 'returns null when not moved' do
+        get api("/projects/#{project.id}/issues/#{issue.iid}", user)
+
+        expect(json_response['moved_to_id']).to be_nil
+      end
+
+      it 'returns issue id when moved' do
+        get api("/projects/#{project.id}/issues/#{moved_issue.iid}", user)
+
+        expect(json_response['moved_to_id']).to eq(issue.id)
+      end
+    end
+
     it 'exposes the closed_at attribute' do
       get api("/projects/#{project.id}/issues/#{closed_issue.iid}", user)
 

spec/requests/api/issues/issues_spec.rb

@@ -832,7 +832,7 @@ describe API::Issues do
     end
 
     context 'when issue does not exist' do
-      it 'returns 404 when trying to move an issue' do
+      it 'returns 404 when trying to delete an issue' do
         delete api("/projects/#{project.id}/issues/123", user)
 
         expect(response).to have_gitlab_http_status(404)