Expose a hasNextPage property to the list results object.

README.md

@@ -1389,31 +1389,22 @@ By default, all results of the first page are retrieved, and the default configu
 ```js
 client.bucket("blog").collection("posts")
   .listRecords({limit: 20})
-  .then(({data, next}) => {
+  .then(({data, hasNextPage, next}) => {
 ```
 
-To retrieve the next page of results, just call `next()` from the result object obtained. If no next page is available, `next()` throws an error you can catch to exit the flow:
+To check if a next page of results is available, you can check for the `hasNextPage` boolean property. To actually fetch the next page of results, call the `next()` function obtained:
 
 ```js
-let getNextPage;
-
 client.bucket("blog").collection("posts")
   .listRecords({limit: 20})
-  .then(({data, next}) => {
-    console.log("Page 1", data);
-    getNextPage = next;
-  });
-```
-
-Later down the flow:
-
-```js
-getNextPage()
-  .then(({data, next}) => {
-    console.log("Page 2", data);
-  })
-  .catch(_ => {
-    console.log("No more pages.");
+  .then(({data, hasNextPage, next}) => {
+    if (hasNextPage) {
+      // resolve with data for page 2
+      return next().then(({data}) => data);
+    } else {
+      // resolve with data for page 1
+      return data;
+    }
   });
 ```
 
@@ -1422,7 +1413,7 @@ Last, if you just want to retrieve and aggregate a given number of result pages,
 ```js
 client.bucket("blog").collection("posts")
   .listRecords({limit: 20, pages: 3})
-  .then(({data, next}) => ...); // A maximum of 60 results will be retrieved here
+  .then(({data, hasNextPage, next}) => ...); // A maximum of 60 results will be retrieved here
 ```
 
 > ##### Notes

src/base.js

@@ -407,7 +407,8 @@ export default class KintoClientBase {
       return {
         last_modified: etag ? etag.replace(/"/g, "") : etag,
         data: results,
-        next: next.bind(null, nextPage)
+        next: next.bind(null, nextPage),
+        hasNextPage: !!nextPage,
       };
     };
 

test/api_test.js

@@ -608,6 +608,11 @@ describe("KintoClient", () => {
         return api.paginatedList(path)
           .should.eventually.have.property("last_modified").eql("42");
       });
+
+      it("should resolve with the hasNextPage being set to false", () => {
+        return api.paginatedList(path)
+          .should.eventually.have.property("hasNextPage").eql(false);
+      });
     });
 
     describe("Filtering", () => {
@@ -693,6 +698,23 @@ describe("KintoClient", () => {
         return api.paginatedList(path, {limit: 2, pages: 2})
           .should.eventually.have.property("data").eql([1, 2, 3]);
       });
+
+      it("should resolve with the hasNextPage being set to true", () => {
+        const { http } = api;
+        sandbox.stub(http, "request")
+          // settings retrieval
+          .onFirstCall().returns(Promise.resolve({
+            json: {settings: {}}
+          }))
+          // first page
+          .onSecondCall().returns(Promise.resolve({
+            headers: {get: () => "http://next-page/"},
+            json: {data: [1, 2]}
+          }));
+
+        return api.paginatedList(path)
+          .should.eventually.have.property("hasNextPage").eql(true);
+      });
     });
 
     describe("Batch mode", () => {

test/integration_test.js

@@ -299,6 +299,11 @@ describe("Integration tests", function() {
             .should.become(["b4", "b3"]);
         });
 
+        it("should expose a hasNextPage boolean prop", () => {
+          return api.listBuckets({limit: 2})
+            .should.eventually.have.property("hasNextPage").eql(true);
+        });
+
         it("should provide a next method to load next page", () => {
           return api.listBuckets({limit: 2})
             .then(res => res.next())