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diff --git a/spec/support/shared_examples/graphql/design_fields_shared_examples.rb b/spec/support/shared_examples/graphql/design_fields_shared_examples.rb
new file mode 100644
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+++ b/spec/support/shared_examples/graphql/design_fields_shared_examples.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+# To use these shared examples, you may define a value in scope named
+# `extra_design_fields`, to pass any extra fields in addition to the
+# standard design fields.
+RSpec.shared_examples 'a GraphQL type with design fields' do
+  let(:extra_design_fields) { [] }
+
+  it { expect(described_class).to require_graphql_authorizations(:read_design) }
+
+  it 'exposes the expected design fields' do
+    expected_fields = %i[
+      id
+      project
+      issue
+      filename
+      full_path
+      image
+      image_v432x230
+      diff_refs
+      event
+      notes_count
+    ] + extra_design_fields
+
+    expect(described_class).to have_graphql_fields(*expected_fields).only
+  end
+
+  describe '#image' do
+    let(:schema) { GitlabSchema }
+    let(:query) { GraphQL::Query.new(schema) }
+    let(:context) { double('Context', schema: schema, query: query, parent: nil) }
+    let(:field) { described_class.fields['image'] }
+    let(:args) { GraphQL::Query::Arguments::NO_ARGS }
+    let(:instance) do
+      object = GitlabSchema.sync_lazy(GitlabSchema.object_from_id(object_id))
+      object_type.authorized_new(object, query.context)
+    end
+    let(:instance_b) do
+      object_b = GitlabSchema.sync_lazy(GitlabSchema.object_from_id(object_id_b))
+      object_type.authorized_new(object_b, query.context)
+    end
+
+    it 'resolves to the design image URL' do
+      image = field.resolve_field(instance, args, context)
+      sha = design.versions.first.sha
+      url = ::Gitlab::Routing.url_helpers.project_design_management_designs_raw_image_url(design.project, design, sha)
+
+      expect(image).to eq(url)
+    end
+
+    it 'has better than O(N) peformance', :request_store do
+      # Assuming designs have been loaded (as they must be), the following
+      # queries are required:
+      # For each distinct version:
+      #  - design_management_versions
+      #    (Request store is needed so that each version is fetched only once.)
+      # For each distinct issue
+      #  - issues
+      # For each distinct project
+      #  - projects
+      #  - routes
+      #  - namespaces
+      # Here that total is:
+      #   - 2 x issues
+      #   - 2 x versions
+      #   - 2 x (projects + routes + namespaces)
+      #   = 10
+      expect(instance).not_to eq(instance_b) # preload designs themselves.
+      expect do
+        image_a = field.resolve_field(instance, args, context)
+        image_b = field.resolve_field(instance, args, context)
+        image_c = field.resolve_field(instance_b, args, context)
+        image_d = field.resolve_field(instance_b, args, context)
+        expect(image_a).to eq(image_b)
+        expect(image_c).not_to eq(image_b)
+        expect(image_c).to eq(image_d)
+      end.not_to exceed_query_limit(10)
+    end
+  end
+end