在PHP中，Fatal Error将显示error_reporting（0）

Question

I had a test interview for a front-end position and the company even wanted to know my php level. I am not so good at php so this is why I put the question here. In a question I had a class named ClassOne, with the a protected method show(). This class was extended by ClassTwo. ClassTwo was instantiated and the show method was invoked on it. In the top of the script I called error_reporting(0).

error_reporting(0);
class ClassOne {
protected function show(){}
}
class ClassTwo extends ClassOne{

}
$obj2 = new ClassTwo(); 
$obj2->show();

I had to say what the code will display and I said "nothing, because show is protected and error_reporting(0) will not let any error to display." Is this right?

Someone told me that this will yield a fatal error and will be displayed even with error_reporting(0). The test was on paper so I don't know the right answer.

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Answer 1

Forget about the classes, and protected methods, and the design. It's all misdirection.

<?php
error_reporting(0);
$obj = new Anything(); 
$obj->do();

Are there any syntax errors? No. PHP parses the script and begins executing it. At line 2 all error reporting is turned off. At line 3 PHP attempts to instantiate the Anything class. The class can't be found, which causes a fatal error. Error reporting was turned off. No error is reported. Nothing to display.

<?php
error_reporting(0);
$obj = new Anything(); 
foo
$obj->do();

Are there any syntax errors? Yes, at line 4. PHP can't parse the script, which causes a "Parse error: syntax error ...". Is error reporting enabled? Line 2 is irrelevant, the script was never executed. Loaded configurations are consulted because PHP loaded fine (e.g. php.ini settings). If error reporting is enabled then a Parse error: syntax error is reported. Is the error displayed? It depends on the environment and other configurations such as display_errors, log_error in a CLI SAPI. Let's assume a straight forward Apache environment with display_errors=1, then the error is displayed.

The error reporting setting is about reporting errors. This doesn't mean that they will be displayed. Errors might be logged and not displayed e.g. for security reasons. Nonetheless, notice that if error reporting is disabled, it doesn't matter if displaying them is enabled because there's nothing to display.