More changes from feedback

Improve/add tests for GraphQL cases in setPage
Remove no cache policy from GraphQL client
Add comment about issue file path

app/assets/javascripts/reports/codequality_report/store/utils/codequality_parser.js

 export const parseCodeclimateMetrics = (issues = [], blobPath = '') => {
   return issues.map((issue) => {
+    // the `file_path` attribute from the artifact is returned as `file` by GraphQL
     const issuePath = issue.file_path || issue.path;
     const parsedIssue = {
       name: issue.description,

ee/app/assets/javascripts/codequality_report/store/utils.js

-import createGqClient, { fetchPolicies } from '~/lib/graphql';
+import createGqClient from '~/lib/graphql';
 
-export const gqClient = createGqClient(
-  {},
-  {
-    fetchPolicy: fetchPolicies.NO_CACHE,
-  },
-);
+export const gqClient = createGqClient();

ee/spec/frontend/codequality_report/store/actions_spec.js

@@ -52,18 +52,49 @@ describe('Codequality report actions', () => {
       );
     });
 
-    it('sets the page number with feature flag enabled', (done) => {
+    describe('with the feature flag enabled', () => {
+      let mockPageInfo;
+
+      beforeEach(() => {
         window.gon = { features: { graphqlCodeQualityFullReport: true } };
+        mockPageInfo = {
+          ...mockGraphqlPagination,
+          currentPage: 11,
+        };
+      });
 
+      it('sets the next page number', (done) => {
         return testAction(
           actions.setPage,
           12,
-        state,
-        [{ type: types.SET_PAGE, payload: { after: '', currentPage: 12 } }],
+          { ...state, pageInfo: mockPageInfo },
+          [
+            {
+              type: types.SET_PAGE,
+              payload: { after: mockGraphqlPagination.endCursor, currentPage: 12 },
+            },
+          ],
           [{ type: 'fetchReport' }],
           done,
         );
       });
+
+      it('sets the previous page number', (done) => {
+        return testAction(
+          actions.setPage,
+          10,
+          { ...state, pageInfo: mockPageInfo },
+          [
+            {
+              type: types.SET_PAGE,
+              payload: { after: mockGraphqlPagination.startCursor, currentPage: 10 },
+            },
+          ],
+          [{ type: 'fetchReport' }],
+          done,
+        );
+      });
+    });
   });
 
   describe('requestReport', () => {