Use identity instead equality

[piotrantosik]

No description provided.

[makasim]

why? array_key_exists always returns boolean

[piotrantosik]

I know but is more readable for psr.
Basically this should be.

if (!array_key_exists($filter, $this->filters)) {
    throw new NonExistingFilterException(sprintf('Could not find configuration  for a filter: %s', $filter));
}

Is acceptable?

[trsteel88]

I prefer false ===