add 'arraybuffer' responseType to XHR

src/browser/tests/net/xhr.html

@@ -125,6 +125,26 @@
   })
 </script>
 
+<script id=xhr6>
+  const req6 = new XMLHttpRequest()
+  testing.async(async (restore) => {
+    await new Promise((resolve) => {
+      req6.onload = resolve;
+      req6.open('GET', 'http://127.0.0.1:9582/xhr/binary')
+      req6.responseType ='arraybuffer'
+      req6.send()
+    });
+
+    restore();
+    testing.expectEqual(200, req6.status);
+    testing.expectEqual('OK', req6.statusText);
+    testing.expectEqual(7, req6.response.byteLength);
+    testing.expectEqual([0, 0, 1, 2, 0, 0, 9], new Int32Array(req6.response));
+    testing.expectEqual('', typeof req6.response);
+    testing.expectEqual('arraybuffer', req6.responseType);
+  });
+</script>
+
 <script id=xhr_redirect>
   testing.async(async (restore) => {
     const req = new XMLHttpRequest();

src/browser/webapi/net/XMLHttpRequest.zig

@@ -69,12 +69,14 @@ const Response = union(ResponseType) {
     text: []const u8,
     json: js.Value.Global,
     document: *Node.Document,
+    arraybuffer: js.ArrayBuffer,
 };
 
 const ResponseType = enum {
     text,
     json,
     document,
+    arraybuffer,
     // TODO: other types to support
 };
 
@@ -302,6 +304,7 @@ pub fn getResponse(self: *XMLHttpRequest, page: *Page) !?Response {
             try page.parseHtmlAsChildren(document.asNode(), data);
             break :blk .{ .document = document };
         },
+        .arraybuffer => .{ .arraybuffer = .{ .values = data } },
     };
 
     self._response = res;

src/testing.zig

@@ -558,6 +558,14 @@ fn testHTTPHandler(req: *std.http.Server.Request) !void {
         });
     }
 
+    if (std.mem.eql(u8, path, "/xhr/binary")) {
+        return req.respond(&.{ 0, 0, 1, 2, 0, 0, 9 }, .{
+            .extra_headers = &.{
+                .{ .name = "Content-Type", .value = "application/octet-stream" },
+            },
+        });
+    }
+
     if (std.mem.startsWith(u8, path, "/src/browser/tests/")) {
         // strip off leading / so that it's relative to CWD
         return TestHTTPServer.sendFile(req, path[1..]);