Refactor AutocompleteControllerdefine-abstraction-levels

This refactors the AutocompleteController according to the guidelines
and boundaries discussed in
https://gitlab.com/gitlab-org/gitlab-ce/issues/49653. Specifically,
ActiveRecord logic is moved to different finders, which are then used in
the controller. View logic in turn is moved to presenters, instead of
directly using ActiveRecord's "to_json" method.

The finder MoveToProjectFinder is also adjusted according to the
abstraction guidelines and boundaries, resulting in a much more simple
finder.

By using finders (and other abstractions) more actively, we can push a
lot of logic out of the controller. We also remove the need for various
"before_action" hooks, though this could be achieved without using
finders as well.

The various finders related to AutcompleteController have also been
moved into a namespace. This removes the need for calling everything
"AutocompleteSmurfFinder", instead you can use
"Autocomplete::SmurfFinder".

2 files changed, 33 insertions, 0 deletions

diff --git a/spec/serializers/move_to_project_entity_spec.rb b/spec/serializers/move_to_project_entity_spec.rb
new file mode 100644
index 00000000000..ac495eadb68
--- /dev/null
+++ b/spec/serializers/move_to_project_entity_spec.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe MoveToProjectEntity do
+  describe '#as_json' do
+    let(:project) { build(:project, id: 1) }
+
+    subject { described_class.new(project).as_json }
+
+    it 'includes the project ID' do
+      expect(subject[:id]).to eq(project.id)
+    end
+
+    it 'includes the full path' do
+      expect(subject[:name_with_namespace]).to eq(project.name_with_namespace)
+    end
+  end
+end
diff --git a/spec/serializers/move_to_project_serializer_spec.rb b/spec/serializers/move_to_project_serializer_spec.rb
new file mode 100644
index 00000000000..841ac969eeb
--- /dev/null
+++ b/spec/serializers/move_to_project_serializer_spec.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe MoveToProjectSerializer do
+  describe '#represent' do
+    it 'includes the name and name with namespace' do
+      project = build(:project, id: 1)
+      output = described_class.new.represent(project)
+
+      expect(output).to include(:id, :name_with_namespace)
+    end
+  end
+end