Bug 1755091 [wpt PR 32825] - Fetch: add tests for Response.json, a=te…

…stonly

Automatic update from web-platform-tests
Fetch: add tests for Response.json

Context: whatwg/fetch#1392.
--

wpt-commits: 27e770bcfbeae534b5d4cbc0a50d2b8247942312
wpt-pr: 32825

testing/web-platform/tests/fetch/api/response/response-static-json.any.js

@@ -0,0 +1,81 @@
+// META: global=window,worker
+// META: title=Response: json static method
+
+const APPLICATION_JSON = "application/json";
+const FOO_BAR = "foo/bar";
+
+const INIT_TESTS = [
+  [undefined, 200, "", APPLICATION_JSON, {}],
+  [{ status: 400 }, 400, "", APPLICATION_JSON, {}],
+  [{ statusText: "foo" }, 200, "foo", APPLICATION_JSON, {}],
+  [{ headers: {} }, 200, "", APPLICATION_JSON, {}],
+  [{ headers: { "content-type": FOO_BAR } }, 200, "", FOO_BAR, {}],
+  [{ headers: { "x-foo": "bar" } }, 200, "", APPLICATION_JSON, { "x-foo": "bar" }],
+];
+
+for (const [init, expectedStatus, expectedStatusText, expectedContentType, expectedHeaders] of INIT_TESTS) {
+  promise_test(async function () {
+    const response = Response.json("hello world", init);
+    assert_equals(response.type, "default", "Response's type is default");
+    assert_equals(response.status, expectedStatus, "Response's status is " + expectedStatus);
+    assert_equals(response.statusText, expectedStatusText, "Response's statusText is " + JSON.stringify(expectedStatusText));
+    assert_equals(response.headers.get("content-type"), expectedContentType, "Response's content-type is " + expectedContentType);
+    for (const key in expectedHeaders) {
+      assert_equals(response.headers.get(key), expectedHeaders[key], "Response's header " + key + " is " + JSON.stringify(expectedHeaders[key]));
+    }
+
+    const data = await response.json();
+    assert_equals(data, "hello world", "Response's body is 'hello world'");
+  }, `Check response returned by static json() with init ${JSON.stringify(init)}`);
+}
+
+const nullBodyStatus = [204, 205, 304];
+for (const status of nullBodyStatus) {
+  test(function () {
+    assert_throws_js(
+      TypeError,
+      function () {
+        Response.json("hello world", { status: status });
+      },
+    );
+  }, `Throws TypeError when calling static json() with a status of ${status}`);
+}
+
+promise_test(async function () {
+  const response = Response.json({ foo: "bar" });
+  const data = await response.json();
+  assert_equals(typeof data, "object", "Response's json body is an object");
+  assert_equals(data.foo, "bar", "Response's json body is { foo: 'bar' }");
+}, "Check static json() encodes JSON objects correctly");
+
+test(function () {
+  assert_throws_js(
+    TypeError,
+    function () {
+      Response.json(Symbol("foo"));
+    },
+  );
+}, "Check static json() throws when data is not encodable");
+
+test(function () {
+  const a = { b: 1 };
+  a.a = a;
+  assert_throws_js(
+    TypeError,
+    function () {
+      Response.json(a);
+    },
+  );
+}, "Check static json() throws when data is circular");
+
+promise_test(async function () {
+  class CustomError extends Error {
+    name = "CustomError";
+  }
+  assert_throws_js(
+    CustomError,
+    function () {
+      Response.json({ get foo() { throw new CustomError("bar") }});
+    }
+  )
+}, "Check static json() propagates JSON serializer errors");