Ensure frozen incoming.pageInfo object not modified.

Quick follow-up to #7224.
apollographql · Oct 27, 2020 · 9a53d3e · 9a53d3e
1 parent e67dae8
commit 9a53d3e
Showing 1 changed file with 11 additions and 2 deletions.
diff --git a/src/utilities/policies/pagination.ts b/src/utilities/policies/pagination.ts
@@ -1,6 +1,7 @@
 import { __rest } from "tslib";
 
 import { FieldPolicy, Reference } from '../../cache';
+import { mergeDeep } from '../common/mergeDeep';
 
 type KeyArgs = FieldPolicy<any>["keyArgs"];
 
@@ -152,11 +153,19 @@ export function relayStylePagination<TNode = Reference>(
         // pageInfo.{start,end}Cursor to {first,last}Edge.cursor.
         const firstCursor = firstEdge && firstEdge.cursor;
         if (firstCursor && !startCursor) {
-          pageInfo.startCursor = firstCursor;
+          incoming = mergeDeep(incoming, {
+            pageInfo: {
+              startCursor: firstCursor,
+            },
+          });
         }
         const lastCursor = lastEdge && lastEdge.cursor;
         if (lastCursor && !endCursor) {
-          pageInfo.endCursor = lastCursor;
+          incoming = mergeDeep(incoming, {
+            pageInfo: {
+              endCursor: lastCursor,
+            },
+          });
         }
       }