Sends notification when proxy depositor specified

Also refactors spec a little bit to:
  * have one expectation per test.
  * use rspec context to describe different conditions.

Closes #1656

app/controllers/concerns/sufia/depositors_controller_behavior.rb

@@ -24,6 +24,7 @@ def create
         head :ok
       else
         grantor.can_receive_deposits_from << grantee
+        send_proxy_depositor_added_messages(grantor, grantee)
         render json: { name: grantee.name, delete_path: sufia.user_depositor_path(grantor.user_key, grantee.user_key) }
       end
     end
@@ -45,5 +46,12 @@ def authorize_and_return_grantor
         authorize! :edit, grantor
         grantor
       end
+
+      def send_proxy_depositor_added_messages(grantor, grantee)
+        message_to_grantee = "#{grantor.name} has assigned you as a proxy depositor"
+        message_to_grantor = "You have assigned #{grantee.name} as a proxy depositor"
+        ::User.batchuser.send_message(grantor, message_to_grantor, "Proxy Depositor Added")
+        ::User.batchuser.send_message(grantee, message_to_grantee, "Proxy Depositor Added")
+      end
   end
 end

spec/controllers/depositors_controller_spec.rb

@@ -9,16 +9,37 @@
       sign_in user
     end
 
-    describe "create" do
-      it "is successful" do
-        expect { post :create, user_id: user.user_key, grantee_id: grantee.user_key, format: 'json' }.to change { ProxyDepositRights.count }.by(1)
-        expect(response).to be_success
+    describe "#create" do
+      context 'when the grantee has not yet been designated as a depositor' do
+        let(:request_to_grant_proxy) { post :create, user_id: user.user_key, grantee_id: grantee.user_key, format: 'json' }
+
+        it 'is successful' do
+          expect { request_to_grant_proxy }.to change { ProxyDepositRights.count }.by(1)
+          expect(response).to be_success
+        end
+
+        it 'sends a message to the grantor' do
+          expect { request_to_grant_proxy }.to change { user.mailbox.inbox.count }.by(1)
+        end
+
+        it 'sends a message to the grantee' do
+          expect { request_to_grant_proxy }.to change { grantee.mailbox.inbox.count }.by(1)
+        end
       end
 
-      it "does not add current user" do
-        expect { post :create, user_id: user.user_key, grantee_id: user.user_key, format: 'json' }.to change { ProxyDepositRights.count }.by(0)
-        expect(response).to be_success
-        expect(response.body).to be_blank
+      context 'when the grantee is already an allowed depositor' do
+        # For this test we just set the grantor to be eq to grantee.
+        let(:redundant_request_to_grant_proxy) { post :create, user_id: user.user_key, grantee_id: user.user_key, format: 'json' }
+
+        it 'does not add the user, and returns a 200, with empty response body' do
+          expect { redundant_request_to_grant_proxy }.to change { ProxyDepositRights.count }.by(0)
+          expect(response).to be_success
+          expect(response.body).to be_blank
+        end
+
+        it 'does not send a message to the user' do
+          expect { redundant_request_to_grant_proxy }.to_not change { user.mailbox.inbox.count }
+        end
       end
     end