WebClient: fix MalformedURLException when setting hash for about:blank

Author: duonglaiquang

src/main/java/org/htmlunit/WebClient.java

@@ -1386,16 +1386,16 @@ private WebResponse makeWebResponseForDataUrl(final WebRequest webRequest) throw
 
     private static WebResponse makeWebResponseForAboutUrl(final WebRequest webRequest) throws MalformedURLException {
         final URL url = webRequest.getUrl();
-        final String urlString = url.toExternalForm();
-        if (UrlUtils.ABOUT_BLANK.equalsIgnoreCase(urlString)) {
-            return new StringWebResponse("", UrlUtils.URL_ABOUT_BLANK);
+        if (UrlUtils.ABOUT.equals(url.getProtocol())) {
+            if ("blank".equalsIgnoreCase(url.getPath())) {
+                if (url.getRef() == null && url.getQuery() == null) {
+                    return new StringWebResponse("", UrlUtils.URL_ABOUT_BLANK);
+                }
+                return new StringWebResponse("", url);
+            }
         }
 
-        final String urlWithoutQuery = StringUtils.substringBefore(urlString, "?");
-        if (!"blank".equalsIgnoreCase(StringUtils.substringAfter(urlWithoutQuery, UrlUtils.ABOUT_SCHEME))) {
-            throw new MalformedURLException(url + " is not supported, only about:blank is supported at the moment.");
-        }
-        return new StringWebResponse("", url);
+        throw new MalformedURLException(url + " is not supported, only about:blank is supported at the moment.");
     }
 
     /**

src/test/java/org/htmlunit/javascript/host/LocationTest.java

@@ -405,6 +405,23 @@ public void setHashUpdatesPageUrl() throws Exception {
         assertEquals("newHash", page.getUrl().getRef());
     }
 
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    public void setHashAboutBlank() throws Exception {
+        try (WebClient webClient = new WebClient()) {
+            HtmlPage page = webClient.getPage("about:blank");
+            assertNull(page.getUrl().getRef());
+
+            page.executeJavaScript("location.hash = 'foo'");
+            assertEquals("foo", page.getUrl().getRef());
+
+            page = (HtmlPage) page.refresh();
+            assertEquals("foo", page.getUrl().getRef());
+        }
+    }
+
     /**
      * @throws Exception if an error occurs
      */