From 98854d12fdebd0f6da9a0030f7c85f1951a38ca3 Mon Sep 17 00:00:00 2001
From: FoxxMD <FoxxMD@users.noreply.github.com>
Date: Wed, 2 Sep 2026 16:56:47 +0000
Subject: [PATCH] fix(tests): Improve network mocking to compensate for
 libraries with frozen imports

* move msw setup into global server that is required before any tests start so primitives are patched before libraries import them
* refactor withRequestInterception to only add/reset handlers instead of server setup/teardown
* run syncBuiltinESMExports to sync patched CJS objects with ESM imports

Primarily fixed mocking lastfm requests but will be useful for future testing.
---
 .mocharc.json                              |  1 +
 src/backend/tests/utils/mswGlobalServer.ts | 21 +++++++++++++++++++++
 src/backend/tests/utils/networking.ts      | 11 +++++++----
 3 files changed, 29 insertions(+), 4 deletions(-)
 create mode 100644 src/backend/tests/utils/mswGlobalServer.ts

diff --git a/.mocharc.json b/.mocharc.json
index db4429b9..efe65a8c 100644
--- a/.mocharc.json
+++ b/.mocharc.json
@@ -3,6 +3,7 @@
   "extension": "ts",
   "spec": "./src/backend/tests/**/*.test.ts",
   "file": [
+    "./src/backend/tests/utils/mswGlobalServer.ts",
     "./src/backend/tests/setup.ts"
   ],
   "exit": true
diff --git a/src/backend/tests/utils/mswGlobalServer.ts b/src/backend/tests/utils/mswGlobalServer.ts
new file mode 100644
index 00000000..c223353b
--- /dev/null
+++ b/src/backend/tests/utils/mswGlobalServer.ts
@@ -0,0 +1,21 @@
+import { setupServer, type SetupServer } from 'msw/node';
+
+/**
+ * Must be loaded (via .mocharc.json "file") before any spec file, and must have no
+ * other imports, so this listen() call wins the race against any library (like
+ * lastfm-ts-api) that freezes a reference to `https.request` at its own module load.
+ * @see https://github.com/nock/nock/issues/2397#issuecomment-1591090893
+ */
+import { syncBuiltinESMExports } from 'node:module';
+
+export const server: SetupServer = setupServer();
+server.listen({ onUnhandledRequest: 'bypass' });
+// Reassigning https.request/http.request only patches the CJS exports object.
+// Named ESM imports of those exports (e.g. `import { request } from 'node:https'`,
+// used by lastfm-ts-api) resolve to a snapshot taken independently of that
+// reassignment, so they never see MSW's patched version without this call.
+// @see https://nodejs.org/api/module.html#modulesyncbuiltinesmexports
+syncBuiltinESMExports();
+server.events.on('request:unhandled', ({ request }) => {
+    console.log('MSW unhandled:', request.method, request.url)
+});
diff --git a/src/backend/tests/utils/networking.ts b/src/backend/tests/utils/networking.ts
index bc2036ac..abddc743 100644
--- a/src/backend/tests/utils/networking.ts
+++ b/src/backend/tests/utils/networking.ts
@@ -1,5 +1,6 @@
-import { setupServer, type SetupServer } from 'msw/node';
+import type { setupServer, SetupServer } from 'msw/node';
 import type {NodeNetworkErrorCode, NodeNetworkException} from "../../common/errors/NodeErrors.ts";
+import { server } from './mswGlobalServer.ts';
 
 export class MockNetworkError extends Error implements NodeNetworkException {
 
@@ -15,17 +16,19 @@ export class MockNetworkError extends Error implements NodeNetworkException {
 
 /**
  * Adapted from https://github.com/nock/nock/issues/2397#issuecomment-1591090893
+ *
+ * Reuses the single process-wide server from mswGlobalServer.ts instead of
+ * listen()/close() per test, since some HTTP clients (e.g. lastfm-ts-api) capture a
+ * reference to https.request at module load time and never see a re-patched one.
  * */
 
 export type ServerOptions = Parameters<typeof setupServer>;
 
 export const withRequestInterception =
     (handlers: ServerOptions, test: (server: SetupServer) => any) => async () => {
-        const server = setupServer(...handlers);
-        server.listen();
+        server.use(...handlers);
 
         return Promise.resolve(test(server)).finally(() => {
             server.resetHandlers();
-            server.close();
         });
 };
-- 
2.51.2