diff --git a/dlls/xmllite/tests/writer.c b/dlls/xmllite/tests/writer.c
index 87cdaabce15..972eb96d9b2 100644
--- a/dlls/xmllite/tests/writer.c
+++ b/dlls/xmllite/tests/writer.c
@@ -1572,6 +1572,27 @@ static void test_indentation(void)
     IXmlWriter_Release(writer);
 }
 
+static HRESULT write_attribute_string(IXmlWriter *writer, const char *prefix, const char *local,
+        const char *uri, const char *value)
+{
+    WCHAR *prefixW, *localW, *uriW, *valueW;
+    HRESULT hr;
+
+    prefixW = strdupAtoW(prefix);
+    localW = strdupAtoW(local);
+    uriW = strdupAtoW(uri);
+    valueW = strdupAtoW(value);
+
+    hr = IXmlWriter_WriteAttributeString(writer, prefixW, localW, uriW, valueW);
+
+    heap_free(prefixW);
+    heap_free(localW);
+    heap_free(uriW);
+    heap_free(valueW);
+
+    return hr;
+}
+
 static void test_WriteAttributeString(void)
 {
     static const struct
@@ -1589,6 +1610,7 @@ static void test_WriteAttributeString(void)
         { NULL, "a", NULL, "b", "<e a=\"b\" />", "<e a=\"b\"" },
         { "prefix", "local", "uri", "b", "<e prefix:local=\"b\" xmlns:prefix=\"uri\" />", "<e prefix:local=\"b\"" },
         { NULL, "a", "http://www.w3.org/2000/xmlns/", "defuri", "<e xmlns:a=\"defuri\" />", "<e xmlns:a=\"defuri\"" },
+        { "xmlns", "a", NULL, "uri", "<e xmlns:a=\"uri\" />", "<e xmlns:a=\"uri\"" },
 
         /* Autogenerated prefix names. */
         { NULL, "a", "defuri", NULL, "<e p1:a=\"\" xmlns:p1=\"defuri\" />", "<e p1:a=\"\"" },
@@ -1606,12 +1628,6 @@ static void test_WriteAttributeString(void)
         { "prefix", "a", "http://www.w3.org/2000/xmlns/", "defuri", "<e />", "<e", WR_E_XMLNSURIDECLARATION },
     };
 
-    static const WCHAR prefixW[] = {'p','r','e','f','i','x',0};
-    static const WCHAR localW[] = {'l','o','c','a','l',0};
-    static const WCHAR uriW[] = {'u','r','i',0};
-    static const WCHAR elementW[] = {'e',0};
-    static const WCHAR aW[] = {'a',0};
-    static const WCHAR bW[] = {'b',0};
     IXmlWriter *writer;
     IStream *stream;
     unsigned int i;
@@ -1624,22 +1640,16 @@ static void test_WriteAttributeString(void)
 
     for (i = 0; i < ARRAY_SIZE(attribute_tests); ++i)
     {
-        WCHAR *prefixW, *localW, *uriW, *valueW;
-
         stream = writer_set_output(writer);
 
         hr = IXmlWriter_WriteStartDocument(writer, XmlStandalone_Omit);
         ok(hr == S_OK, "Failed to start document, hr %#x.\n", hr);
 
-        hr = IXmlWriter_WriteStartElement(writer, NULL, elementW, NULL);
+        hr = write_start_element(writer, NULL, "e", NULL);
         ok(hr == S_OK, "Failed to start element, hr %#x.\n", hr);
 
-        prefixW = strdupAtoW(attribute_tests[i].prefix);
-        localW = strdupAtoW(attribute_tests[i].local);
-        uriW = strdupAtoW(attribute_tests[i].uri);
-        valueW = strdupAtoW(attribute_tests[i].value);
-
-        hr = IXmlWriter_WriteAttributeString(writer, prefixW, localW, uriW, valueW);
+        hr = write_attribute_string(writer, attribute_tests[i].prefix, attribute_tests[i].local,
+                attribute_tests[i].uri, attribute_tests[i].value);
     todo_wine_if(i != 0)
         ok(hr == attribute_tests[i].hr, "%u: unexpected hr %#x.\n", i, hr);
 
@@ -1654,11 +1664,6 @@ static void test_WriteAttributeString(void)
         hr = IXmlWriter_Flush(writer);
         ok(hr == S_OK, "Failed to flush, hr %#x.\n", hr);
 
-        heap_free(prefixW);
-        heap_free(localW);
-        heap_free(uriW);
-        heap_free(valueW);
-
         check_output(stream, attribute_tests[i].output, i == 1 || i == 2 || i == 3 || i == 4, __LINE__);
         IStream_Release(stream);
     }
@@ -1669,21 +1674,20 @@ static void test_WriteAttributeString(void)
     hr = IXmlWriter_WriteStartDocument(writer, XmlStandalone_Omit);
     ok(hr == S_OK, "got 0x%08x\n", hr);
 
-    hr = IXmlWriter_WriteStartElement(writer, NULL, aW, NULL);
+    hr = write_start_element(writer, "p", "a", "outeruri");
     ok(hr == S_OK, "got 0x%08x\n", hr);
 
-    hr = IXmlWriter_WriteAttributeString(writer, aW, NULL, NULL, bW);
-todo_wine
-    ok(hr == E_INVALIDARG, "got 0x%08x\n", hr);
-
-    hr = IXmlWriter_WriteAttributeString(writer, prefixW, localW, uriW, bW);
+    hr = write_attribute_string(writer, "prefix", "local", "uri", "b");
 todo_wine
     ok(hr == S_OK, "got 0x%08x\n", hr);
 
-    hr = IXmlWriter_WriteAttributeString(writer, NULL, aW, NULL, bW);
+    hr = write_attribute_string(writer, NULL, "a", NULL, "b");
     ok(hr == S_OK, "got 0x%08x\n", hr);
 
-    hr = IXmlWriter_WriteAttributeString(writer, prefixW, localW, NULL, bW);
+    hr = write_attribute_string(writer, "p", "attr", NULL, "value");
+    ok(hr == S_OK, "Failed to write attribute string, hr %#x.\n", hr);
+
+    hr = write_attribute_string(writer, "prefix", "local", NULL, "b");
 todo_wine
     ok(hr == WR_E_DUPLICATEATTRIBUTE, "got 0x%08x\n", hr);
 
@@ -1694,7 +1698,7 @@ todo_wine
     ok(hr == S_OK, "got 0x%08x\n", hr);
 
     CHECK_OUTPUT_TODO(stream,
-        "<a prefix:local=\"b\" a=\"b\" xmlns:prefix=\"uri\" />");
+        "<p:a prefix:local=\"b\" a=\"b\" p:attr=\"value\" xmlns:prefix=\"uri\" xmlns:p=\"outeruri\" />");
 
     IXmlWriter_Release(writer);
     IStream_Release(stream);