fix(types): correct pagination return type for data which is an array (#662)

* fix(types): correct pagination return type for data which is an array

Instead of returning `T` in `GetPaginationKeys<T>`, we return an empty object, because T would be an `OctokitResponse<T, S>`, and there is no response data in the `data` field

Fixes #661

* test: add test for array response pagination

* style: prettier

Author: wolfy1339

src/types.ts

@@ -28,6 +28,11 @@ import type { PaginatingEndpoints } from "./generated/paginating-endpoints.js";
 //     : never
 //   : never;
 
+type PaginationMetadataKeys =
+  | "repository_selection"
+  | "total_count"
+  | "incomplete_results";
+
 // https://stackoverflow.com/a/58980331/206879
 type KnownKeys<T> = Extract<
   {
@@ -36,10 +41,7 @@ type KnownKeys<T> = Extract<
     ? U
     : never,
   // Exclude keys that are known to not contain the data
-  Exclude<
-    keyof T,
-    "repository_selection" | "total_count" | "incomplete_results"
-  >
+  Exclude<keyof T, PaginationMetadataKeys>
 >;
 type KeysMatching<T, V> = {
   [K in keyof T]: T[K] extends V ? K : never;
@@ -56,15 +58,9 @@ type GetResultsType<T> = T extends { data: any[] }
 
 // Extract the pagination keys from the response object in order to return them alongside the paginated results
 type GetPaginationKeys<T> = T extends { data: any[] }
-  ? T
+  ? {}
   : T extends { data: object }
-    ? Pick<
-        T["data"],
-        Extract<
-          keyof T["data"],
-          "repository_selection" | "total_count" | "incomplete_results"
-        >
-      >
+    ? Pick<T["data"], Extract<keyof T["data"], PaginationMetadataKeys>>
     : never;
 
 // Ensure that the type always returns the paginated results and not a mix of paginated results and the response object

test/validate-typescript.ts

@@ -195,6 +195,20 @@ export async function requestMethodWithNamespacedResponse() {
   }
 }
 
+// https://github.com/octokit/plugin-paginate-rest.js/issues/661
+// Ensure the endpoints that return an array don't have an extra `OctokitResponse` in the data
+type Package =
+  PaginatingEndpoints["GET /orgs/{org}/packages/{package_type}/{package_name}/versions"]["response"]["data"][0];
+export async function requestWithArrayResponse() {
+  const results = await octokit.paginate(
+    "GET /orgs/{org}/packages/{package_type}/{package_name}/versions",
+  );
+  for (const result of results) {
+    const pkg: Package = result;
+    console.log(pkg.name);
+  }
+}
+
 export async function paginatingEndpointKeyProvidedByUser<
   R extends keyof PaginatingEndpoints,
 >(route: R) {