add tests for avatar upload

spec/controllers/users_controller_spec.rb

@@ -45,17 +45,37 @@
     end
 
     context 'successful' do
-      it 'should update attributes' do
+      it 'should update privacy' do
         new_private = !(@user.private)
         put :update, id: @user, user: { private: new_private }
         expect(@user.reload.private).to be new_private
+        expect(flash[:success]).to be_present
       end
 
       it 'should update dagschotel' do
         product = create :product
         put :update, id: @user, user: { dagschotel_id:  product.id }
         expect(@user.reload.dagschotel).to eq(product)
       end
+
+      it 'should accept real images' do
+        file = fixture_file_upload('files/real-image.png', 'image/png')
+        put :update, id: @user, user: { avatar: file }
+        expect(flash[:success]).to be_present
+      end
+    end
+
+    context 'danger zone' do
+      it 'should warn for NOPs' do
+        put :update, id: @user, user: {}
+        expect(flash[:notice]).to be_present
+      end
+
+      it 'should not accept unreal images' do
+        file = fixture_file_upload('files/unreal-image.svg', 'image/svg+xml')
+        put :update, id: @user, user: { avatar: file }
+        expect(flash[:error]).to be_present
+      end
     end
   end