Move json parsing to client code outside service

app/assets/javascripts/issuable/related_issues/services/related_issues_service.js

@@ -10,26 +10,22 @@ class RelatedIssuesService {
 
   // eslint-disable-next-line class-methods-use-this
   fetchIssueInfo(endpoint) {
-    return Vue.http.get(endpoint)
-      .then(res => res.json());
+    return Vue.http.get(endpoint);
   }
 
   fetchRelatedIssues() {
-    return this.relatedIssuesResource.get()
-      .then(res => res.json());
+    return this.relatedIssuesResource.get();
   }
 
   addRelatedIssues(newIssueReferences) {
     return this.relatedIssuesResource.save({}, {
       issue_references: newIssueReferences,
-    })
-      .then(res => res.json());
+    });
   }
 
   // eslint-disable-next-line class-methods-use-this
   removeRelatedIssue(endpoint) {
-    return Vue.http.delete(endpoint)
-      .then(res => res.json());
+    return Vue.http.delete(endpoint);
   }
 }
 

spec/javascripts/issuable/related_issues/services/related_issues_service_spec.js

@@ -34,6 +34,7 @@ describe('RelatedIssuesService', () => {
 
     it('fetch issue info', (done) => {
       service.fetchIssueInfo('...')
+        .then(res => res.json())
         .then((issue) => {
           expect(issue).toEqual(issuable1);
           done();
@@ -61,6 +62,7 @@ describe('RelatedIssuesService', () => {
 
     it('fetch related issues', (done) => {
       service.fetchRelatedIssues()
+        .then(res => res.json())
         .then((relatedIssues) => {
           expect(relatedIssues).toEqual([issuable1]);
           done();
@@ -91,6 +93,7 @@ describe('RelatedIssuesService', () => {
 
     it('add related issues', (done) => {
       service.addRelatedIssues([issuable1.reference])
+        .then(res => res.json())
         .then((resData) => {
           expect(resData.status).toEqual('success');
           done();
@@ -121,6 +124,7 @@ describe('RelatedIssuesService', () => {
 
     it('remove related issue', (done) => {
       service.removeRelatedIssue('...')
+        .then(res => res.json())
         .then((resData) => {
           expect(resData.status).toEqual('success');
           done();