1 files changed, 125 insertions, 0 deletions
diff --git a/testing/web-platform/tests/fetch/api/response/response-init-contenttype.any.js b/testing/web-platform/tests/fetch/api/response/response-init-contenttype.any.js
new file mode 100644
index 0000000000..3a7744c287
--- /dev/null
+++ b/testing/web-platform/tests/fetch/api/response/response-init-contenttype.any.js
@@ -0,0 +1,125 @@
+test(() => {
+  const response = new Response();
+  assert_equals(response.headers.get("Content-Type"), null);
+}, "Default Content-Type for Response with empty body");
+
+test(() => {
+  const blob = new Blob([]);
+  const response = new Response(blob);
+  assert_equals(response.headers.get("Content-Type"), null);
+}, "Default Content-Type for Response with Blob body (no type set)");
+
+test(() => {
+  const blob = new Blob([], { type: "" });
+  const response = new Response(blob);
+  assert_equals(response.headers.get("Content-Type"), null);
+}, "Default Content-Type for Response with Blob body (empty type)");
+
+test(() => {
+  const blob = new Blob([], { type: "a/b; c=d" });
+  const response = new Response(blob);
+  assert_equals(response.headers.get("Content-Type"), "a/b; c=d");
+}, "Default Content-Type for Response with Blob body (set type)");
+
+test(() => {
+  const buffer = new Uint8Array();
+  const response = new Response(buffer);
+  assert_equals(response.headers.get("Content-Type"), null);
+}, "Default Content-Type for Response with buffer source body");
+
+promise_test(async () => {
+  const formData = new FormData();
+  formData.append("a", "b");
+  const response = new Response(formData);
+  const boundary = (await response.text()).split("\r\n")[0].slice(2);
+  assert_equals(
+    response.headers.get("Content-Type"),
+    `multipart/form-data; boundary=${boundary}`,
+  );
+}, "Default Content-Type for Response with FormData body");
+
+test(() => {
+  const usp = new URLSearchParams();
+  const response = new Response(usp);
+  assert_equals(
+    response.headers.get("Content-Type"),
+    "application/x-www-form-urlencoded;charset=UTF-8",
+  );
+}, "Default Content-Type for Response with URLSearchParams body");
+
+test(() => {
+  const response = new Response("");
+  assert_equals(
+    response.headers.get("Content-Type"),
+    "text/plain;charset=UTF-8",
+  );
+}, "Default Content-Type for Response with string body");
+
+test(() => {
+  const stream = new ReadableStream();
+  const response = new Response(stream);
+  assert_equals(response.headers.get("Content-Type"), null);
+}, "Default Content-Type for Response with ReadableStream body");
+
+// -----------------------------------------------------------------------------
+
+const OVERRIDE_MIME = "test/only; mime=type";
+
+function responseWithOverrideMime(body) {
+  return new Response(
+    body,
+    { headers: { "Content-Type": OVERRIDE_MIME } },
+  );
+}
+
+test(() => {
+  const response = responseWithOverrideMime(undefined);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with empty body");
+
+test(() => {
+  const blob = new Blob([]);
+  const response = responseWithOverrideMime(blob);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with Blob body (no type set)");
+
+test(() => {
+  const blob = new Blob([], { type: "" });
+  const response = responseWithOverrideMime(blob);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with Blob body (empty type)");
+
+test(() => {
+  const blob = new Blob([], { type: "a/b; c=d" });
+  const response = responseWithOverrideMime(blob);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with Blob body (set type)");
+
+test(() => {
+  const buffer = new Uint8Array();
+  const response = responseWithOverrideMime(buffer);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with buffer source body");
+
+test(() => {
+  const formData = new FormData();
+  const response = responseWithOverrideMime(formData);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with FormData body");
+
+test(() => {
+  const usp = new URLSearchParams();
+  const response = responseWithOverrideMime(usp);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with URLSearchParams body");
+
+test(() => {
+  const response = responseWithOverrideMime("");
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with string body");
+
+test(() => {
+  const stream = new ReadableStream();
+  const response = responseWithOverrideMime(stream);
+  assert_equals(response.headers.get("Content-Type"), OVERRIDE_MIME);
+}, "Can override Content-Type for Response with ReadableStream body");