TYPO3 Core

Well, it is desired that the value 2 prevents the errors from showing up in FE.
So if the error message shall not be shown to the user in FE (except from devs via devIPmask), what else should happen?

IMO there's only one solution: Either get your code working, or catch the exceptions on your own and show appropriate error messages.

Markus, thank you for the answer.

But the problem is in fact, that even surrounding code with try-catch will not help, because no Exception will be thrown. It will not even be processed by registered ProductionExceptionHandler.

It may not show any errors in FE, but it must interrupt script execution, since it is Fatal Error, you know.

Also description in Install Tool is misleading, as I described above.

Ok, I agree the execution shall be stopped.

You can of course capture the exception. You need to try..catch the call to processObject or any other method that is under your control.
The core's ExceptionHandlers are only trigged as last resort.

Unfortunately you can't.

See this example, please. It is very simplified version of ErrorHandler from TYPO3.

<?php
function myErrorHandler($errno, $errstr, $errfile, $errline) {
  if ( E_RECOVERABLE_ERROR===$errno ) {
    echo "handled catchable fatal error\n";
    //throw new ErrorException($errstr, $errno, 0, $errfile, $errline);
  }
  //return false;
  return true;
}
set_error_handler('myErrorHandler');

class ClassA {
  public function method_a (ClassB $b) {
      echo "Inside of method_a()\n";
  }
}

class ClassWrong{}

try{
  $a = new ClassA;
  $a->method_a(new ClassWrong);
}
catch(Exception $ex) {
  echo "catched Exception\n";
}
echo "done.";

You see: "Inside of method_a()" is output as well as "done".
So, I've appeared inside of method_a(), wile shouldn't and at same time didn't catch any exception.

Uncommenting Line 7 will interrupt execution, but still will not throw any exception.
And only line 5 will make catch() block work.

thanks for the example, sorry, I mixed things up here.

The error handler actually creates the exception first hand. It captures the php error and converts it to an exception.
Of course it is not so easy to catch this exception.

Markus, thank you for the note, but this is only partly true.

Exception is created by ErrorHandler only in case, which can be seen here: https://github.com/TYPO3/TYPO3.CMS/blob/TYPO3_6-1/typo3/sysext/core/Classes/Error/ErrorHandler.php#L94-L109

But with [SYS][displayErrors] = 2, $this->exceptionalErrors becomes '0', so the 'if' condition from the code of ErrorHandler doesn't work and we land to 'else', which only writes log and returns 'TRUE' and so the code continues execution and no exception can be caught.

Therefore the minimum fix, which can be provided here: do not always return TRUE.

Maybe, do something, like this:

switch ($errorLevel) {
    case E_USER_ERROR:
    case E_RECOVERABLE_ERROR:
        return FALSE;

    case E_USER_WARNING:
    case E_WARNING:
    default:
        return TRUE;
}

BTW, same happens with 6.2 too, as I can see from the code.

Hi!

I read through the whole code now (6.3) and agree that it is a mess.

Basically we have to deal with two things: Errors (generated by PHP parser) and Exceptions (generated by code).

The options for [SYS][displayErrors] and what they really do: * -1 TYPO3 does not touch the PHP setting 'display_errors', but still converts most errors into exceptions, which are handled by the registered exceptionHandler then. If the devIPmask matches, exceptions are shown using the debugExceptionHandler for more details. * 0 TYPO3 sets PHP setting display_errors to 0, so no PHP errors are shown in FE. Moreover no error is converted into an exception, so the errorHandler will handle all of them. * 1 TYPO3 sets PHP setting display_errors to 1, so PHP errors are shown in FE. Most errors will be converted to exceptions and will be handled by the debugExceptionHandler. * 2 If devIPmask matches [SYS][displayErrors] is set to 1, otherwise to 0

At any configuration execution must be stopped in case of a non-user error.

Notes: Setting '1' will also display the error as a flash message, if it isn't converted to an exception.

I'll push a cleanup of the code first and we can discuss further solutions then.

I created another ticket for the cleanup: #61235

Many thanks for fast patching!

Tested under same conditions - all looks good for me.

Patch set 2 for branch master of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at http://review.typo3.org/32465

Patch set 3 for branch master of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at http://review.typo3.org/32465

Patch set 1 for branch TYPO3_6-2 of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at http://review.typo3.org/33491

Patch set 1 for branch TYPO3_6-1 of project Packages/TYPO3.CMS has been pushed to the review server.
It is available at http://review.typo3.org/33492