fix: ignore passthrough requests for expectRequestsToMatchHandler

Author: matthieugicquel

src/expectRequestsToMatchHandlers.test.ts

@@ -1,6 +1,12 @@
-import { expect, it, afterEach } from "vitest";
-
-import { createMockServer, installInterceptor, resetMockServers } from ".";
+import { expect, it, afterEach, beforeAll, describe } from "vitest";
+
+import {
+  createMockServer,
+  installInterceptor,
+  passthrough,
+  resetMockServers,
+  uninstallInterceptor,
+} from ".";
 import { expectRequestsToMatchHandlers } from "./expectRequestsToMatchHandlers";
 
 installInterceptor();
@@ -201,3 +207,29 @@ it("logs a persistent handler mismatch for an unhandled request", async () => {
     "
   `);
 });
+
+describe("passthrough", () => {
+  beforeAll(() => {
+    uninstallInterceptor();
+    installInterceptor({ onUnhandled: passthrough });
+
+    return () => {
+      uninstallInterceptor();
+      installInterceptor();
+    };
+  });
+
+  it("doesn't throw because of passthrough request", async () => {
+    const localMockServer = createMockServer("http://0.0.0.0");
+
+    // control
+    localMockServer.get("/test", body);
+    const response = await fetch("http://0.0.0.0/test");
+    expect(response.ok).toEqual(true);
+
+    await expect(() => fetch("http://0.0.0.0/not-mocked")).rejects.toThrowError();
+
+    // real expectation
+    expect(getThrownMessage()).toBeUndefined();
+  });
+});

src/index.test.ts

@@ -1,5 +1,5 @@
 import axios from "axios";
-import { expect, it, describe, afterEach, vi, beforeAll } from "vitest";
+import { expect, it, describe, afterEach, vi, beforeEach } from "vitest";
 
 import {
   createMockServer,
@@ -548,9 +548,8 @@ describe("server-level config", () => {
 });
 
 describe("interceptor-level config", () => {
-  beforeAll(() => {
+  beforeEach(() => {
     uninstallInterceptor();
-    installInterceptor({ onUnhandled: passthrough });
 
     return () => {
       uninstallInterceptor();
@@ -559,6 +558,8 @@ describe("interceptor-level config", () => {
   });
 
   it("lets a request passthrough", async () => {
+    installInterceptor({ onUnhandled: passthrough });
+
     const localMockServer = createMockServer("http://0.0.0.0");
 
     // control
@@ -569,4 +570,14 @@ describe("interceptor-level config", () => {
     // real expectation
     await expect(() => fetch("http://0.0.0.0/not-mocked")).rejects.toThrowError();
   });
+
+  it("uses custom onUnhandled", async () => {
+    installInterceptor({ onUnhandled: () => new Response("custom onUnhandled", { status: 500 }) });
+
+    const response = await fetch("https://test.com/test");
+
+    expect(response.ok).toEqual(false);
+    expect(response.status).toEqual(500);
+    expect(await response.text()).toEqual("custom onUnhandled");
+  });
 });

src/server.ts

@@ -7,6 +7,9 @@ export const createServer = (setupInterceptor: SetupInterceptor, config?: Interc
   const HandledRequests = new Map<Handler, Request>();
   const MatchingLog = new Set<MatchingLogEntry>();
 
+  const handleUnhandled =
+    config?.onUnhandled ?? (() => new Response("No matching handler", { status: 404 }));
+
   const dispose = setupInterceptor((request) => {
     const requestLog = new Set<MatchingLogEntry>();
     const explain = (handler: Handler) => (message: string) => {
@@ -32,14 +35,18 @@ export const createServer = (setupInterceptor: SetupInterceptor, config?: Interc
       }
     }
 
-    for (const logEntry of requestLog) MatchingLog.add(logEntry);
-    UnhandledRequests.add(request);
+    const unhandledResponse = handleUnhandled(request);
+
+    if (unhandledResponse) {
+      // This request should have been handled
+      for (const logEntry of requestLog) MatchingLog.add(logEntry);
+      UnhandledRequests.add(request);
 
-    const onUnhandled =
-      config?.onUnhandled ??
-      (() => new Response(JSON.stringify({ message: "No matching handler" }), { status: 404 }));
+      return unhandledResponse;
+    }
 
-    return onUnhandled(request);
+    // let the request passthrough
+    return;
   });
 
   return {