TYPO3 Core

There are calls in the file ext_localconf.php of extensions, e.g. tt_products:

if (!defined ('PATH_BE_ttproducts')) {
define('PATH_BE_ttproducts', t3lib_extMgm::extPath(TT_PRODUCTS_EXTkey));
}

This is to have a constant for the path to the extension in the backend. $TYPO3_LOADED_EXT['tt_products'] is not yet true, because tt_products is in the process to be loaded. So it must also be checked if the global $_EXTKEY == 'tt_product' and not to raise an exception. And the second bug is that this exception is not caught anywhere.

public static function extPath($key, $script = '') {
global $TYPO3_LOADED_EXT;
if (!isset($TYPO3_LOADED_EXT[$key])) {
throw new BadFunctionCallException(
'TYPO3 Fatal Error: Extension key "'.$key.'" was NOT loaded!',
1270853878
);
}
return PATH_site.$TYPO3_LOADED_EXT[$key]['siteRelPath'].$script;
}

It seems like you shouldn't do such things in ext_localconf.php, when the extension isn't loaded, yet.
Therefore it's okay to throw an exception.

Did this work with 4.3? I think exceptions only took over places where before printError() messages have been shown.

Yes, this is allowed in former versions of extensions.

I have found now the reason for this error now.
I have had a renaming error. The folder name for tt_products has been tt_product. This error has occured due to this wrong name of the folder name of the extension.

The only thing which is needed here is that this exception should be caught. It is the wrong way to block everything because of a simple naming error.

it was a die before, so only difference is that you get more informations now.

I close this bug report.

This error (white TYPO3 backend without any displayed error message) is still present in TYPO3 4.7.2.

PHP error_log:

[Mon Oct 29 07:39:25 2012] [error] [client 42.28.98.142] PHP Fatal error: Uncaught exception 'BadFunctionCallException' with message 'TYPO3 Fatal Error: Extension "tt_products" was NOT found!' in /var/www/mydomain/web/typo3_src-4.7.2/t3lib/class.t3lib_extmgm.php:105\nStack trace:\n#0 /var/www/mydomain/web/typo3_src-4.7.2/t3lib/class.t3lib_autoloader.php(171): t3lib_extMgm::extPath('tt_products', 'ext_autoload.ph...')\n#1 /var/www/mydomain/web/typo3_src-4.7.2/t3lib/class.t3lib_autoloader.php(121): t3lib_autoloader::createCoreAndExtensionRegistry()\n#2 /var/www/mydomain/web/typo3_src-4.7.2/t3lib/class.t3lib_autoloader.php(69): t3lib_autoloader::loadCoreAndExtensionRegistry()\n#3 /var/www/mydomain/web/typo3_src-4.7.2/t3lib/config_default.php(799): t3lib_autoloader::registerAutoloader()\n#4 /var/www/mydomain/web/typo3_src-4.7.2/typo3/init.php(201): require('/var/www/mydomain/...')\n#5 /var/www/mydomain/web/typo3_src-4.7.2/typo3/index.php(38): require('/var/www/mydomain/...')\n#6 {main}\n thrown in /var/www/mydomain/web/typo3_src-4.7.2/t3lib/class.t3lib_extmgm.php on line 105

These things are missing:

1. The TYPO3 backend should never go away if it does not find an extension which formerly has been installed. The extension is not needed at all to have a working TYPO3 backend. There is no need at all to stop here.

2. The TYPO3 frontend should not show a white page when something is wrong. It should at least point the user into the right direction. It could say 'TYPO3 Fatal Error: Extension key "tt_products" was NOT loaded! Check your log file for more information.' Why should the user not be informed about this?