Base custom request options on defaults, and add basic tests for makeProxyRequestOptions

src/api-client.test.ts

@@ -2,6 +2,7 @@ import * as github from "@actions/github";
 import * as githubUtils from "@actions/github/lib/utils";
 import test from "ava";
 import * as sinon from "sinon";
+import { ProxyAgent } from "undici";
 
 import * as actionsUtil from "./actions-util";
 import * as api from "./api-client";
@@ -251,3 +252,23 @@ test("getRegistryProxyConfig - gets the configuration from the env vars", async
     )
     .passes(t.like, { host, port, ca });
 });
+
+test("makeProxyRequestOptions - returns defaults without custom proxy", async (t) => {
+  t.deepEqual(
+    api.makeProxyRequestOptions(undefined),
+    githubUtils.defaults.request,
+  );
+});
+
+test("makeProxyRequestOptions - returns fetch with custom proxy", async (t) => {
+  const opts = api.makeProxyRequestOptions(
+    new ProxyAgent("http://localhost:1080"),
+  );
+  // Fetch should be different from the defaults.
+  t.notDeepEqual(opts?.fetch, githubUtils.defaults.request?.fetch);
+  // The options should be the same aside from that.
+  t.deepEqual(
+    { ...opts, fetch: githubUtils.defaults.request?.fetch },
+    githubUtils.defaults.request,
+  );
+});

src/api-client.ts

@@ -108,12 +108,19 @@ export function getRegistryProxy(
  * Constructs a `RequestRequestOptions` with a custom `fetch` implementation
  * that uses `dispatcher` as a proxy for requests.
  *
- * @param dispatcher The proxy to use.
+ * @param dispatcher The proxy to use, if any.
  */
 export function makeProxyRequestOptions(
-  dispatcher: ProxyAgent,
-): RequestRequestOptions {
+  dispatcher: ProxyAgent | undefined,
+): RequestRequestOptions | undefined {
+  // If we don't have a custom `ProxyAgent`, return the defaults.
+  if (dispatcher === undefined) {
+    return githubUtils.defaults.request;
+  }
+
+  // Otherwise, construct the custom `fetch` and add it onto the defaults.
   return {
+    ...githubUtils.defaults.request,
     fetch: (req: RequestInfo, init?: RequestInit) => {
       return undiciFetch(req, { ...init, dispatcher });
     },
@@ -136,10 +143,7 @@ function createApiClientWithDetails(
   const auth =
     (allowExternal && apiDetails.externalRepoAuth) || apiDetails.auth;
   const retryingOctokit = githubUtils.GitHub.plugin(retry.retry);
-  const requestOptions =
-    proxy === undefined
-      ? githubUtils.defaults.request
-      : makeProxyRequestOptions(proxy);
+  const requestOptions = makeProxyRequestOptions(proxy);
   return new retryingOctokit(
     githubUtils.getOctokitOptions(auth, {
       baseUrl: apiDetails.apiURL,