Issue 1795 - Add helper std::wstring GetLocationUrl(IWebBrowser2& browser)

src/plugin/PluginUtil.cpp

+/*
+ * This file is part of Adblock Plus <https://adblockplus.org/>,
+ * Copyright (C) 2006-2015 Eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 #include "PluginStdAfx.h"
 #include <algorithm>
 #include <stdexcept>
 #include <vector>
 
 #include "../shared/Utils.h"
 #include "PluginUtil.h"
 #include "PluginSettings.h"
 
 std::wstring HtmlFolderPath()
@@ skipping 13 matching lines @@
 
 std::wstring FileUrl(const std::wstring& path)
 {
   std::wstring url = path;
   std::replace(url.begin(), url.end(), L'\\', L'/');
   return L"file:///" + url;
 }
 
 std::wstring GetLocationUrl(IWebBrowser2& browser)
 {
-  std::wstring retValue;

[Eric, 2015/01/13 17:04:20]

Use of this variable requires extraneous assignments.

[sergei, 2015/01/29 12:42:11]

I've changed the body of this function and removed `retValue`.

   ATL::CComBSTR locationUrl;
-  if (SUCCEEDED(browser.get_LocationURL(&locationUrl)) && !!locationUrl)

[Eric, 2015/01/13 17:04:20]

No need for double negation. Testing a converted pointer as boolean is
completely reliable, and it's the pattern used for CComBSTR extensively in the
code.

+  if (FAILED(browser.get_LocationURL(&locationUrl)) || !locationUrl)
   {
-    retValue.assign(locationUrl, locationUrl.Length());

[Eric, 2015/01/13 17:04:20]

return std::wstring(locationUrl, locationUrl.Length());

+    return std::wstring();
   }
-  return retValue;

[Eric, 2015/01/13 17:04:20]

return L"";
 -- or --
return std:;wstring();

+  return std::wstring(locationUrl, locationUrl.Length());
 }