dont overwrite page info when args are not passed to relayStylePagina…

…tion
apollographql · Sep 3, 2020 · a19f732 · a19f732
1 parent 9c825de
commit a19f732
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Showing 3 changed files with 93 additions and 25 deletions.
diff --git a/src/cache/inmemory/__tests__/__snapshots__/policies.ts.snap b/src/cache/inmemory/__tests__/__snapshots__/policies.ts.snap
@@ -797,3 +797,36 @@ Object {
   },
 }
 `;
+
+exports[`type policies field policies can handle Relay-style pagination without args 2`] = `
+Object {
+  "ROOT_QUERY": Object {
+    "__typename": "Query",
+    "todos": Object {
+      "edges": Array [
+        Object {
+          "__typename": "TodoEdge",
+          "cursor": "YXJyYXljb25uZWN0aW9uOjI=",
+          "node": Object {
+            "__ref": "Todo:1",
+          },
+        },
+      ],
+      "extraMetaData": "extra",
+      "pageInfo": Object {
+        "__typename": "PageInfo",
+        "endCursor": "YXJyYXljb25uZWN0aW9uOjI=",
+        "hasNextPage": true,
+        "hasPreviousPage": false,
+        "startCursor": "YXJyYXljb25uZWN0aW9uOjI=",
+      },
+      "totalCount": 1293,
+    },
+  },
+  "Todo:1": Object {
+    "__typename": "Todo",
+    "id": "1",
+    "title": "Fix the tests",
+  },
+}
+`;
diff --git a/src/cache/inmemory/__tests__/policies.ts b/src/cache/inmemory/__tests__/policies.ts
@@ -2189,15 +2189,15 @@ describe("type policies", function () {
         },
       });
 
-      const initialQuery = gql`
+      const firstQuery = gql`
         query TodoQuery {
           todos {
             totalCount
           }
         }
       `
 
-      const query = gql`
+      const secondQuery = gql`
         query TodoQuery {
           todos(after: $after, first: $first) {
             pageInfo {
@@ -2218,11 +2218,20 @@ describe("type policies", function () {
         }
       `
 
-      const firstVariables = {
+      const thirdQuery = gql`
+        query TodoQuery {
+          todos {
+            totalCount
+            extraMetaData
+          }
+        }
+      `
+
+      const secondVariables = {
         first: 1,
       };
 
-      const firstEdges = [
+      const secondEdges = [
         {
           __typename: "TodoEdge",
           node: {
@@ -2233,7 +2242,7 @@ describe("type policies", function () {
         },
       ];
 
-      const firstPageInfo = {
+      const secondPageInfo = {
         __typename: "PageInfo",
         endCursor: "YXJyYXljb25uZWN0aW9uOjI=",
         hasNextPage: true,
@@ -2242,7 +2251,7 @@ describe("type policies", function () {
       const link = new MockLink([
         {
           request: {
-            query: initialQuery,
+            query: firstQuery,
           },
           result: {
             data: {
@@ -2254,24 +2263,37 @@ describe("type policies", function () {
         },
         {
           request: {
-            query,
-            variables: firstVariables,
+            query: secondQuery,
+            variables: secondVariables,
           },
           result: {
             data: {
               todos: {
-                edges: firstEdges,
-                pageInfo: firstPageInfo,
+                edges: secondEdges,
+                pageInfo: secondPageInfo,
                 totalCount: 1292,
               }
             }
           },
         },
+        {
+          request: {
+            query: thirdQuery,
+          },
+          result: {
+            data: {
+              todos: {
+                totalCount: 1293,
+                extraMetaData: 'extra',
+              }
+            }
+          },
+        }
       ]).setOnError(reject);
 
       const client = new ApolloClient({ link, cache });
 
-      client.query({query: initialQuery}).then(result => {
+      client.query({query: firstQuery}).then(result => {
         expect(result).toEqual({
           loading: false,
           networkStatus: NetworkStatus.ready,
@@ -2298,21 +2320,35 @@ describe("type policies", function () {
           }
         });
 
-        client.query({query, variables: firstVariables}).then(result => {
+        client.query({query: secondQuery, variables: secondVariables}).then(result => {
           expect(result).toEqual({
             loading: false,
             networkStatus: NetworkStatus.ready,
             data: {
               todos: {
-                edges: firstEdges,
-                pageInfo: firstPageInfo,
+                edges: secondEdges,
+                pageInfo: secondPageInfo,
                 totalCount: 1292,
               }
             }
           })
 
           expect(cache.extract()).toMatchSnapshot()
-          resolve()
+
+          client.query({query: thirdQuery}).then(result => {
+            expect(result).toEqual({
+              loading: false,
+              networkStatus: NetworkStatus.ready,
+              data: {
+                todos: {
+                  totalCount: 1293,
+                  extraMetaData: 'extra',
+                }
+              }
+            })
+            expect(cache.extract()).toMatchSnapshot()
+            resolve()
+          })
         })
       })
     })

diff --git a/src/utilities/policies/pagination.ts b/src/utilities/policies/pagination.ts
@@ -57,7 +57,7 @@ type TInternalRelay<TNode> = Readonly<{
 // anything about connections, edges, cursors, or pageInfo objects.
 export function relayStylePagination<TNode = Reference>(
   keyArgs: KeyArgs = false,
-): FieldPolicy<TInternalRelay<TNode>> {
+): FieldPolicy<TInternalRelay<TNode>, Partial<TInternalRelay<TNode>>> {
   return {
     keyArgs,
 
@@ -79,42 +79,41 @@ export function relayStylePagination<TNode = Reference>(
     },
 
     merge(existing = makeEmptyData(), incoming, { args }) {
-      if (!args) return {...existing, ...incoming};
-
-      const incomingEdges = (incoming.edges || []).slice(0);
-      if (incoming.pageInfo) {
+      const incomingEdges = incoming.edges?.slice(0);
+      if (incoming.pageInfo && incomingEdges) {
         updateCursor(incomingEdges, 0, incoming.pageInfo.startCursor);
         updateCursor(incomingEdges, -1, incoming.pageInfo.endCursor);
       }
 
       let prefix = existing.edges;
       let suffix: typeof prefix = [];
 
-      if (args.after) {
+      if (args?.after) {
         const index = prefix.findIndex(edge => edge.cursor === args.after);
         if (index >= 0) {
           prefix = prefix.slice(0, index + 1);
           // suffix = []; // already true
         }
-      } else if (args.before) {
+      } else if (args?.before) {
         const index = prefix.findIndex(edge => edge.cursor === args.before);
         suffix = index < 0 ? prefix : prefix.slice(index);
         prefix = [];
       } else {
         // If we have neither args.after nor args.before, the incoming
         // edges cannot be spliced into the existing edges, so they must
         // replace the existing edges. See #6592 for a motivating example.
-        prefix = [];
+        if(incomingEdges)
+          prefix = [];
       }
 
       const edges = [
         ...prefix,
-        ...incomingEdges,
+        ...(incomingEdges || []),
         ...suffix,
       ];
 
       const pageInfo = {
-        ...incoming.pageInfo,
+        ...(incoming.pageInfo || {}),
         ...existing.pageInfo,
         startCursor: cursorFromEdge(edges, 0),
         endCursor: cursorFromEdge(edges, -1),