fix(fetch): preserve properties of Request by default (#145)

src/patch/fetch.js

@@ -11,9 +11,15 @@ const Xhook = function(url, options) {
   if (options == null) {
     options = { headers: {} };
   }
-  options.url = url;
+
   let request = null;
 
+  if (url instanceof Request) {
+    request = url
+  } else {
+    options.url = url;
+  }
+
   const beforeHooks = hooks.listeners("before");
   const afterHooks = hooks.listeners("after");
 

tests/fetch/fetch-header.spec.ts

@@ -0,0 +1,22 @@
+import { test, expect } from "@playwright/test";
+import { createWaitting } from '../test.util';
+
+test("Should preserve headers of Request", async ({ page }) => {
+    const url = "http://127.0.0.1:8080/example/common.html"
+    await page.goto(url);
+    const { waitting, $resolve } = createWaitting()
+    page.on('requestfinished', (req) => {
+        $resolve(req.headers())
+    })
+    await page.evaluate((url) => {
+        const req = new Request(url, {
+            headers: {
+                "custom-xhook-header": "1"
+            }
+        })
+        fetch(req)
+    }, url)
+    const headers = await waitting;
+    expect(headers).toMatchObject({ 'custom-xhook-header': '1' })
+});
+