From 63fc7c71d1523d6f677f4712787015ecfbf405e1 Mon Sep 17 00:00:00 2001
From: Brian Kim <briankimpossible@gmail.com>
Date: Fri, 27 Aug 2021 11:48:28 -0400
Subject: [PATCH] Fix cached data being returned in getCurrentResult for
 certain fetch policies

Fixes #8697
---
 src/core/ObservableQuery.ts           | 21 +++++++++++++++------
 src/core/__tests__/ObservableQuery.ts |  4 ++--
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index 9bd4808a5fb..b070cdd89c1 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -207,21 +207,30 @@ export class ObservableQuery<
       networkStatus,
     } as ApolloQueryResult<TData>;
 
-    // If this.options.query has @client(always: true) fields, we cannot trust
-    // diff.result, since it was read from the cache without running local
-    // resolvers (and it's too late to run resolvers now, since we must return a
-    // result synchronously).
-    if (!this.queryManager.transform(this.options.query).hasForcedResolvers) {
+    const { fetchPolicy = "cache-first" } = this.options;
+    const shouldReturnCachedData = lastResult || (
+      fetchPolicy !== 'network-only' &&
+      fetchPolicy !== 'no-cache' &&
+      fetchPolicy !== 'standby'
+    );
+    if (
+      shouldReturnCachedData &&
+      // If this.options.query has @client(always: true) fields, we cannot
+      // trust diff.result, since it was read from the cache without running
+      // local resolvers (and it's too late to run resolvers now, since we must
+      // return a result synchronously).
+      !this.queryManager.transform(this.options.query).hasForcedResolvers
+    ) {
       const diff = this.queryInfo.getDiff();
 
       if (diff.complete || this.options.returnPartialData) {
         result.data = diff.result;
       }
+
       if (equal(result.data, {})) {
         result.data = void 0 as any;
       }
 
-      const { fetchPolicy = "cache-first" } = this.options;
       if (diff.complete) {
         // If the diff is complete, and we're using a FetchPolicy that
         // terminates after a complete cache read, we can assume the next
diff --git a/src/core/__tests__/ObservableQuery.ts b/src/core/__tests__/ObservableQuery.ts
index 4111121355b..45abeaa2ebe 100644
--- a/src/core/__tests__/ObservableQuery.ts
+++ b/src/core/__tests__/ObservableQuery.ts
@@ -2027,7 +2027,7 @@ describe('ObservableQuery', () => {
         });
 
         expect(observable.getCurrentResult()).toEqual({
-          data: dataOne,
+          data: undefined,
           loading: true,
           networkStatus: NetworkStatus.loading,
         });
@@ -2036,7 +2036,7 @@ describe('ObservableQuery', () => {
           if (handleCount === 1) {
             expect(subResult).toEqual({
               loading: true,
-              data: dataOne,
+              data: undefined,
               networkStatus: NetworkStatus.loading,
             });
           } else if (handleCount === 2) {