Remove the `/merge_request_urls` from internal API

This was added in
https://gitlab.com/gitlab-org/gitlab-foss/merge_requests/5542 but has
been replaced by the post receive call in https://gitlab.com/gitlab-org/gitlab-foss/merge_requests/13916

doc/development/internal_api.md

@@ -115,16 +115,6 @@ curl --request POST --header "Gitlab-Shared-Secret: <Base64 encoded token>" --da
 
 - GitLab-shell
 
-## Get merge requests for a ref [NOT USED]
-
-```
-GET /internal/merge_request_urls
-```
-
-**Deprecated**: This used to be called from GitLab shell to fetch the
-merge requests for a change to output them after a push, but this is
-now handled in the `/internal/post_receive` call.
-
 ## Authorized Keys Check
 
 This endpoint is called by the GitLab-shell authorized keys

lib/api/internal/base.rb

@@ -112,10 +112,6 @@ module API
         end
         # rubocop: enable CodeReuse/ActiveRecord
 
-        get "/merge_request_urls" do
-          merge_request_urls
-        end
-
         #
         # Get a ssh key using the fingerprint
         #

spec/requests/api/internal/base_spec.rb

@@ -770,47 +770,6 @@ describe API::Internal::Base do
     end
   end
 
-  describe 'GET /internal/merge_request_urls' do
-    let(:repo_name) { "#{project.full_path}" }
-    let(:changes) { URI.escape("#{Gitlab::Git::BLANK_SHA} 570e7b2abdd848b95f2f578043fc23bd6f6fd24d refs/heads/new_branch") }
-
-    before do
-      project.add_developer(user)
-    end
-
-    it 'returns link to create new merge request' do
-      get api("/internal/merge_request_urls?project=#{repo_name}&changes=#{changes}"), params: { secret_token: secret_token }
-
-      expect(json_response).to match [{
-        "branch_name" => "new_branch",
-        "url" => "http://#{Gitlab.config.gitlab.host}/#{project.full_path}/merge_requests/new?merge_request%5Bsource_branch%5D=new_branch",
-        "new_merge_request" => true
-      }]
-    end
-
-    it 'returns empty array if printing_merge_request_link_enabled is false' do
-      project.update!(printing_merge_request_link_enabled: false)
-
-      get api("/internal/merge_request_urls?project=#{repo_name}&changes=#{changes}"), params: { secret_token: secret_token }
-
-      expect(json_response).to eq([])
-    end
-
-    context 'with a gl_repository parameter' do
-      let(:gl_repository) { "project-#{project.id}" }
-
-      it 'returns link to create new merge request' do
-        get api("/internal/merge_request_urls?gl_repository=#{gl_repository}&changes=#{changes}"), params: { secret_token: secret_token }
-
-        expect(json_response).to match [{
-          "branch_name" => "new_branch",
-          "url" => "http://#{Gitlab.config.gitlab.host}/#{project.full_path}/merge_requests/new?merge_request%5Bsource_branch%5D=new_branch",
-          "new_merge_request" => true
-        }]
-      end
-    end
-  end
-
   # TODO: Uncomment when the end-point is reenabled
   # describe 'POST /notify_post_receive' do
   #   let(:valid_params) do
@@ -951,6 +910,19 @@ describe API::Internal::Base do
       expect(json_response['messages']).to include(build_basic_message(message))
     end
 
+    it 'returns the link to an existing merge request when it exists' do
+      merge_request = create(:merge_request, source_project: project, source_branch: branch_name, target_branch: 'master')
+
+      post api('/internal/post_receive'), params: valid_params
+
+      message = <<~MESSAGE.strip
+        View merge request for feature:
+          #{project_merge_request_url(project, merge_request)}
+      MESSAGE
+
+      expect(json_response['messages']).to include(build_basic_message(message))
+    end
+
     it 'returns no merge request messages if printing_merge_request_link_enabled is false' do
       project.update!(printing_merge_request_link_enabled: false)