add XHR::SetRequestHeader Step 3 unit test

tests/unit/script/dom/xmlhttprequest.rs

@@ -0,0 +1,27 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use script::dom::xmlhttprequest::trim_http_whitespace;
+
+#[test]
+fn test_trim_http_whitespace() {
+    fn test_trim(in_: &[u8], out: &[u8]) {
+        let b = trim_http_whitespace(in_);
+        assert_eq!(b, out);
+    }
+
+    test_trim(b"", b"");
+
+    test_trim(b" ", b"");
+    test_trim(b"a", b"a");
+    test_trim(b" a", b"a");
+    test_trim(b"a ", b"a");
+    test_trim(b" a ", b"a");
+
+    test_trim(b"\t", b"");
+    test_trim(b"a", b"a");
+    test_trim(b"\ta", b"a");
+    test_trim(b"a\t", b"a");
+    test_trim(b"\ta\t", b"a");
+}

tests/unit/script/lib.rs

@@ -11,4 +11,5 @@ extern crate util;
 #[cfg(test)] mod dom {
     mod bindings;
     mod blob;
+    mod xmlhttprequest;
 }