chore: import upstream snapshot with attribution

test/helpers/localHttpServer.ts

@@ -0,0 +1,75 @@
+import http, { type IncomingMessage, type ServerResponse } from 'http';
+
+export interface RecordedRequest {
+  method: string;
+  url: string;
+  headers: http.IncomingHttpHeaders;
+  body: Buffer;
+}
+
+export interface LocalHttpServer {
+  baseUrl: string;
+  requests: RecordedRequest[];
+  close: () => Promise<void>;
+}
+
+export async function startLocalHttpServer(
+  handler: (
+    request: RecordedRequest,
+    response: ServerResponse,
+  ) => void | Promise<void>,
+): Promise<LocalHttpServer> {
+  const requests: RecordedRequest[] = [];
+  const server = http.createServer(
+    async (request: IncomingMessage, response: ServerResponse) => {
+      const chunks: Buffer[] = [];
+      request.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
+      request.on('end', async () => {
+        const recorded: RecordedRequest = {
+          method: request.method || 'GET',
+          url: request.url || '/',
+          headers: request.headers,
+          body: Buffer.concat(chunks),
+        };
+        requests.push(recorded);
+
+        try {
+          await handler(recorded, response);
+        } catch (error: any) {
+          response.writeHead(500, { 'Content-Type': 'application/json' });
+          response.end(
+            JSON.stringify({
+              code: 500,
+              msg: error?.message || 'local test server error',
+            }),
+          );
+        }
+      });
+    },
+  );
+
+  await new Promise<void>((resolve, reject) => {
+    server.once('error', reject);
+    server.listen(0, '127.0.0.1', () => {
+      server.off('error', reject);
+      resolve();
+    });
+  });
+
+  const address = server.address();
+  if (!address || typeof address === 'string') {
+    throw new Error('Failed to start local HTTP server');
+  }
+
+  return {
+    baseUrl: `http://127.0.0.1:${address.port}`,
+    requests,
+    close: () =>
+      new Promise((resolve, reject) => {
+        server.close((error) => {
+          if (error) reject(error);
+          else resolve();
+        });
+      }),
+  };
+}