Add test for filter posts by category

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

@@ -32,6 +32,26 @@ const postQueryWithCategories = `
     }
   }
 `
+const createPostWithoutCategoriesVariables = {
+  title: 'This is a post without categories',
+  content: 'I should be able to filter it out',
+  categoryIds: null,
+}
+const postQueryFilteredByCategory = `
+  query($name: String) {
+    Post(filter: { categories_some: { name: $name } }) {
+      title
+      id
+      categories {
+        name
+      }
+    }
+  }
+`
+const postCategoriesFilterParam = 'Environment & Nature'
+const postQueryFilteredByCategoryVariables = {
+  name: postCategoriesFilterParam,
+}
 beforeEach(async () => {
   await factory.create('User', {
     email: 'test@example.org',
@@ -124,7 +144,8 @@ describe('CreatePost', () => {
     })
 
     describe('categories', () => {
-      it('allows a user to set the categories of the post', async () => {
+      let postWithCategories
+      beforeEach(async () => {
         await Promise.all([
           factory.create('Category', {
             id: 'cat9',
@@ -142,11 +163,14 @@ describe('CreatePost', () => {
             icon: 'shopping-cart',
           }),
         ])
-        const expected = [{ id: 'cat9' }, { id: 'cat4' }, { id: 'cat15' }]
-        const postWithCategories = await client.request(
+        postWithCategories = await client.request(
           createPostWithCategoriesMutation,
           creatPostWithCategoriesVariables,
         )
+      })
+
+      it('allows a user to set the categories of the post', async () => {
+        const expected = [{ id: 'cat9' }, { id: 'cat4' }, { id: 'cat15' }]
         const postQueryWithCategoriesVariables = {
           id: postWithCategories.CreatePost.id,
         }
@@ -154,6 +178,28 @@ describe('CreatePost', () => {
           client.request(postQueryWithCategories, postQueryWithCategoriesVariables),
         ).resolves.toEqual({ Post: [{ categories: expect.arrayContaining(expected) }] })
       })
+
+      it('allows a user to filter for posts by category', async () => {
+        await client.request(createPostWithCategoriesMutation, createPostWithoutCategoriesVariables)
+        const categoryNames = [
+          { name: 'Democracy & Politics' },
+          { name: 'Environment & Nature' },
+          { name: 'Consumption & Sustainability' },
+        ]
+        const expected = {
+          Post: [
+            {
+              title: postTitle,
+              id: postWithCategories.CreatePost.id,
+              categories: expect.arrayContaining(categoryNames),
+            },
+          ],
+        }
+
+        await expect(
+          client.request(postQueryFilteredByCategory, postQueryFilteredByCategoryVariables),
+        ).resolves.toEqual(expected)
+      })
     })
   })
 })