RemovePostEmotions should return deleted object

@mattwr18 I prefer (I believe it's even best practice) that a delete
mutation should return the deleted object. If you run the delete
mutation again, it should return `null` because there is no object like
that anymore. That way the client knows if a delete mutation has changed
any state in the database.

Also I fixed another bug in the resolver. If your graphql mutation looks
like this:

```gql
mutation {
  RemovePostEmotions(to:{ id:"p15"}, data:{emotion: angry}) {
    from {
      id
      name
    }
    to {
      id
      title
    }
    emotion
  }
}
```

Then you get errors because your resolver does not return the name for
the user or the title for the post anymore. Just use spread operator...
and it's fixed.

backend/src/schema/resolvers/posts.js

@@ -84,9 +84,9 @@ export default {
       session.close()
       const [emoted] = transactionRes.records.map(record => {
         return {
-          from: { id: record.get('userFrom').properties.id },
+          from: { ...record.get('userFrom').properties },
-          to: { id: record.get('postTo').properties.id },
+          to: { ...record.get('postTo').properties },
-          emotion: record.get('emotedRelation').properties.emotion,
+          ...record.get('emotedRelation').properties,
         }
       })
       return emoted
@@ -98,16 +98,18 @@ export default {
       const transactionRes = await session.run(
         `MATCH (userFrom:User {id: $from})-[emotedRelation:EMOTED {emotion: $data.emotion}]->(postTo:Post {id: $to.id})
         DELETE emotedRelation
-        RETURN userFrom
+        RETURN userFrom, postTo`,
-        `,
         { from, to, data },
       )
       session.close()
-      const [userFrom] = transactionRes.records.map(record => {
+      const [emoted] = transactionRes.records.map(record => {
-        return record.get('userFrom')
+        return {
+          from: { ...record.get('userFrom').properties },
+          to: { ...record.get('postTo').properties },
+          emotion: data.emotion,
+        }
       })
-      if (!userFrom) throw new Error('Not Authorised!')
+      return emoted
-      return Boolean(userFrom)
     },
   },
   Query: {

backend/src/schema/resolvers/posts.spec.js

@@ -588,7 +588,15 @@ describe('emotions', () => {
     let removePostEmotionsVariables, postsEmotionsQueryVariables
     const removePostEmotionsMutation = gql`
       mutation($to: _PostInput!, $data: _EMOTEDInput!) {
-        RemovePostEmotions(to: $to, data: $data)
+        RemovePostEmotions(to: $to, data: $data) {
+          from {
+            id
+          }
+          to {
+            id
+          }
+          emotion
+        }
       }
     `
     beforeEach(async () => {
@@ -616,21 +624,31 @@ describe('emotions', () => {
 
     describe('authenticated', () => {
       describe('but not the emoter', () => {
-        it('throws an authorization error', async () => {
+        it('returns null if the emotion could not be found', async () => {
           user = someUser
           const removePostEmotions = await postMutationAction(
             user,
             removePostEmotionsMutation,
             removePostEmotionsVariables,
           )
-          expect(removePostEmotions.errors[0]).toHaveProperty('message', 'Not Authorised!')
+          expect(removePostEmotions).toEqual(
+            expect.objectContaining({ data: { RemovePostEmotions: null } }),
+          )
         })
       })
 
       describe('as the emoter', () => {
         it('removes an emotion from a post', async () => {
           user = owner
-          const expected = { data: { RemovePostEmotions: true } }
+          const expected = {
+            data: {
+              RemovePostEmotions: {
+                to: { id: postToEmote.id },
+                from: { id: user.id },
+                emotion: 'cry',
+              },
+            },
+          }
           await expect(
             postMutationAction(user, removePostEmotionsMutation, removePostEmotionsVariables),
           ).resolves.toEqual(expect.objectContaining(expected))

backend/src/schema/types/type/Post.gql

@@ -92,7 +92,7 @@ type Mutation {
     categoryIds: [ID]
   ): Post
   AddPostEmotions(to: _PostInput!, data: _EMOTEDInput!): EMOTED
-  RemovePostEmotions(to: _PostInput!, data: _EMOTEDInput!): Boolean!
+  RemovePostEmotions(to: _PostInput!, data: _EMOTEDInput!): EMOTED
 }
 
 type Query {

webapp/components/Emotions/Emotions.spec.js

@@ -26,7 +26,6 @@ describe('Emotions.vue', () => {
           .mockResolvedValueOnce({
             data: {
               AddPostEmotions: {
-                from: { id: 'u176' },
                 to: { id: 'p143' },
                 data: { emotion: 'happy' },
               },
@@ -34,7 +33,11 @@ describe('Emotions.vue', () => {
           })
           .mockResolvedValueOnce({
             data: {
-              RemovePostEmotions: true,
+              RemovePostEmotions: {
+                from: { id: 'u176' },
+                to: { id: 'p143' },
+                data: { emotion: 'happy' },
+              },
             },
           }),
         query: jest.fn().mockResolvedValue({
@@ -85,7 +88,7 @@ describe('Emotions.vue', () => {
       it('sends the AddPostEmotionsMutation for an emotion when clicked', () => {
         expectedParams = {
           mutation: PostMutations().AddPostEmotionsMutation,
-          variables: { from: { id: 'u176' }, to: { id: 'p143' }, data: { emotion: 'funny' } },
+          variables: { to: { id: 'p143' }, data: { emotion: 'funny' } },
         }
         expect(mocks.$apollo.mutate).toHaveBeenCalledWith(expect.objectContaining(expectedParams))
       })
@@ -106,7 +109,7 @@ describe('Emotions.vue', () => {
         it('sends the RemovePostEmotionsMutation when a user clicks on an active emotion', () => {
           expectedParams = {
             mutation: PostMutations().RemovePostEmotionsMutation,
-            variables: { from: { id: 'u176' }, to: { id: 'p143' }, data: { emotion: 'funny' } },
+            variables: { to: { id: 'p143' }, data: { emotion: 'funny' } },
           }
           expect(mocks.$apollo.mutate).toHaveBeenCalledWith(expect.objectContaining(expectedParams))
         })

webapp/components/Emotions/Emotions.vue

@@ -56,7 +56,6 @@ export default {
             ? PostMutations().RemovePostEmotionsMutation
             : PostMutations().AddPostEmotionsMutation,
           variables: {
-            from: { id: this.currentUser.id },
             to: { id: this.post.id },
             data: { emotion },
           },

webapp/graphql/PostMutations.js

@@ -75,7 +75,15 @@ export default () => {
     `,
     RemovePostEmotionsMutation: gql`
       mutation($to: _PostInput!, $data: _EMOTEDInput!) {
-        RemovePostEmotions(to: $to, data: $data)
+        RemovePostEmotions(to: $to, data: $data) {
+          emotion
+          from {
+            id
+          }
+          to {
+            id
+          }
+        }
       }
     `,
   }