When I install this module I get the following error: Fatal error: Cannot redeclare drupal_error_levels() in /home/X/public_html/X/includes/errors.inc on line 16.
I get this error message when activating and then trying to configure the testing module ...
any news on this? the module is completely un-usable as far as I can see
Same here, when activating and then trying to configure the testing module.
So @macman, why do you think it is a Calendar error, not a Core Testing error?
In my case the error was caused by a faulty PHP opcode mechanism.
I just started seeing this error when I tried cloning a display from a view that had nothing to do with calendar. In fact I have had the calendar module installed and working fine for weeks, so I knew it wasn't directly related to this error.
The only thing I had changed recently (beyond simple template mods) was installing XCache on the server. So I turned XCache off, and the error went away.
This is clearly not a Calendar bug, as it never declares drupal_error_levels(). As #4 suggests, it's probably caused by a buggy opcode cache.
Automatically closed -- issue fixed for 2 weeks with no activity.
Related: Why I'm getting 'Cannot redeclare drupal_error_levels()' error?
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