Solution

Explanation of the Bug

If you're interested, here's an explanation of the bug - how and why it occurs.

• The bug seems to occur in only Joomla 1.5 and above.
• If you're familiar with Google Adsense Search, your Google Adsense ID is passed to Google with the URL parameter client.
• Internally in Joomla 1.5, there is also a "client identifier" with the value 0, 1, 2 or 3. If you're interested, you can get a more detailed explanation about this client identifier in the file: libraries/joomla/application/helper.php, class JApplicationHelper, function &getClientInfo().
• If you take a look at the original function in administrator/components/com_sh404sef/sh404sef.class.php to retrieve the client identifier as highlighted above:

function shGetFrontEndActiveLanguages() {

  $shLangs = array();
  // Initialize some variables
  $client =& JApplicationHelper::getClientInfo(JRequest::getVar('client', '0', '', 'int'));

The first parameter is the parameter name 'client'. The second is the default value, which is '0'. The third is '', which in this case refers to $_REQUEST. The last is the data type, which is 'int'.

Because of the third parameter '' which refers to $_REQUEST, if you've specified your Google Adsense ID, the highlighted line above will read your Google Adsense ID and returned it as the client identifier. Note: this is the main reason why the error disappears if you did not specify your Google Adsense ID.

The last parameter 'int' will force your Google Sense ID (e.g. pub-1234567812345678 which is an alphanumeric value) to be converted to an integer, which usually results in a large negative integer value. However, in Joomla, the client identifier can only have the value 0, 1, 2 or 3.

As a result of the above, JApplicationHelper::getClientInfo() doesn't return a valid ClientInfo class.

And the following line

$path = JLanguage::getLanguagePath($client->path);

causes the infamous error

JFolder::folder: Path is not a folder: /language
• To fix the error, I used another Joomla function to retrieve the client identifier

JFactory::getApplication()->getClientId()

with a valid client identifier, I can proceed to retrieve a valid ClientInfo class:

$client =& JApplicationHelper::getClientInfo(JFactory::getApplication()->getClientId());

Of course, we'll only do this if we're running googleSearch. Hence the conditional statement:

if (JRequest::getVar('option', '')=='com_googlesearch') {

• So the complete solution is as follows:

function shGetFrontEndActiveLanguages() {

  $shLangs = array();
  // Initialize some variables
  if (preg_match('/com_googlesearch/', JRequest::getVar('option', ''))) {) {
      $client =& JApplicationHelper::getClientInfo(JFactory::getApplication()->getClientId());
  } else {
      $client =& JApplicationHelper::getClientInfo(JRequest::getVar('client', '0', '', 'int'));
  }