Add mutation toggling WIP state of merge requests

This is mainly the setup of mutations for GraphQL. Including
authorization and basic return type-structure.

1 files changed, 68 insertions, 0 deletions

diff --git a/spec/requests/api/graphql/mutations/merge_requests/set_wip_spec.rb b/spec/requests/api/graphql/mutations/merge_requests/set_wip_spec.rb
new file mode 100644
index 00000000000..8f427d71a32
--- /dev/null
+++ b/spec/requests/api/graphql/mutations/merge_requests/set_wip_spec.rb
@@ -0,0 +1,68 @@
+require 'spec_helper'
+
+describe 'Setting WIP status of a merge request' do
+  include GraphqlHelpers
+
+  let(:current_user) { create(:user) }
+  let(:merge_request) { create(:merge_request) }
+  let(:project) { merge_request.project }
+  let(:input) { { wip: true } }
+
+  let(:mutation) do
+    variables = {
+      project_path: project.full_path,
+      iid: merge_request.iid
+    }
+    graphql_mutation(:merge_request_set_wip, variables.merge(input))
+  end
+
+  def mutation_response
+    graphql_mutation_response(:merge_request_set_wip)
+  end
+
+  before do
+    project.add_developer(current_user)
+  end
+
+  it 'returns an error if the user is not allowed to update the merge request' do
+    post_graphql_mutation(mutation, current_user: create(:user))
+
+    expect(graphql_errors).not_to be_empty
+  end
+
+  it 'marks the merge request as WIP' do
+    post_graphql_mutation(mutation, current_user: current_user)
+
+    expect(response).to have_gitlab_http_status(:success)
+    expect(mutation_response['mergeRequest']['title']).to start_with('WIP:')
+  end
+
+  it 'does not do anything if the merge request was already marked `WIP`' do
+    merge_request.update!(title: 'wip: hello world')
+
+    post_graphql_mutation(mutation, current_user: current_user)
+
+    expect(response).to have_gitlab_http_status(:success)
+    expect(mutation_response['mergeRequest']['title']).to start_with('wip:')
+  end
+
+  context 'when passing WIP false as input' do
+    let(:input) { { wip: false } }
+
+    it 'does not do anything if the merge reqeust was not marked wip' do
+      post_graphql_mutation(mutation, current_user: current_user)
+
+      expect(response).to have_gitlab_http_status(:success)
+      expect(mutation_response['mergeRequest']['title']).not_to start_with(/wip\:/)
+    end
+
+    it 'unmarks the merge request as `WIP`' do
+      merge_request.update!(title: 'wip: hello world')
+
+      post_graphql_mutation(mutation, current_user: current_user)
+
+      expect(response).to have_gitlab_http_status(:success)
+      expect(mutation_response['mergeRequest']['title']).not_to start_with('/wip\:/')
+    end
+  end
+end