Can't filter by "is_done" BAD ARGUMENT

Posted on behalf of Jacob Raccuia. Original post date 2014-04-17

Here is my URL:

/workspaces/{$this->workspace_id}/events?filter[]=project_id=11754768&filter[]=is_done is true

The filter works fine when I remove is_done. When it's there, I get the below error. I am using the API with PHP. I get similar errors when I use other filter variables.

stdClass Object
(
    [type] => Error
    [error] => BadArgument
    [message] => operation: '' must be: is
)