Fix regression causing on{Error,Completed} not to be called (#9226)

Author: mmahalwy

CHANGELOG.md

@@ -1,3 +1,10 @@
+## Apollo Client 3.5.7 (unreleased)
+
+### Bug Fixes
+
+- Fix regression that prevented `onError` or `onCompleted` from being called in some cases when using `useQuery`. <br/>
+  [@mmahalwy](https://github.com/mmahalwy) in [#9226](https://github.com/apollographql/apollo-client/pull/9226)
+
 ## Apollo Client 3.5.6 (2021-12-07)
 
 ### Bug Fixes (by [@brainkim](https://github.com/brainkim) in [#9144](https://github.com/apollographql/apollo-client/pull/9144))

src/react/hooks/__tests__/useQuery.test.tsx

@@ -1545,17 +1545,20 @@ describe('useQuery Hook', () => {
       await waitForNextUpdate();
       expect(result.current.loading).toBe(false);
       expect(result.current.data).toEqual(data1);
+      expect(onCompleted).toHaveBeenLastCalledWith(data1);
 
       rerender({ variables: { first: 2 } });
       expect(result.current.loading).toBe(true);
 
       await waitForNextUpdate();
       expect(result.current.loading).toBe(false);
       expect(result.current.data).toEqual(data2);
+      expect(onCompleted).toHaveBeenLastCalledWith(data2);
 
       rerender({ variables: { first: 1 } });
       expect(result.current.loading).toBe(false);
       expect(result.current.data).toEqual(data1);
+      expect(onCompleted).toHaveBeenLastCalledWith(data1);
 
       expect(onCompleted).toHaveBeenCalledTimes(3);
     });

src/react/hooks/useQuery.ts

@@ -134,12 +134,10 @@ export function useQuery<
 
       setResult(ref.current.result = nextResult);
       if (!nextResult.loading && options) {
-        if (!result.loading) {
-          if (result.error) {
-            options.onError?.(result.error);
-          } else if (result.data) {
-            options.onCompleted?.(result.data);
-          }
+        if (nextResult.error) {
+          options.onError?.(nextResult.error);
+        } else if (nextResult.data) {
+          options.onCompleted?.(nextResult.data);
         }
       }
     }