The PHP editor doesn't highlight usage of undefined functions and parameters.
Because php is have the possibility to add parameters on the fly this should just be a warning.
Also functions can be dynamic via the __call function, but on classes without __call a warning can be displayed.
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Maybe some hint could be added.
this would be very useful; you can forget to create a method and find out only 3 months later, in production, when your code crashes at runtime;
this makes php a terrible language compared to java and c#
since php introduced "declare(strict_types=1)" and made it possible to remove the silent type conversion, which is another nightmare in php, this is the biggest source of bugs