No Missing Argument

July 2, 2015 ยท View on GitHub

PHP does not check at compile time that a function or method calls has enough arguments. One may call any function with any number of argument, and this will be checked at execution time. Extra arguments will be dropped, but missing arguments will generate an error.

This is true for PHP native functions too.

<?php

function x($a, $b, $c = 2) { return $a + $b; }

x(); // missing arguments 0 and 1
x('a'); // missing arguments 1 

?>

It is recommended to provide an acceptable number of arguments, depending on default values in the function signature.

Rule Details

This rule spots functions and methods calls with less arguments than needed.

When the called method makes use of variable number of argument, using func_get_args, func_get_arg or func_num_args, or even the ... operator, the number of acceptable arguments is.

The following codes are considered a warning:

<?php

function x($a, $b, $c = 2) { return $a + $b; }

function z($a, ...$b) { 	return array_sum($b) + $a; }

x(); // missing arguments 0 and 1
x('a'); // missing arguments 1 
x('a', 'b', 'c', 'd'); // arguments 4 will be ignore 

z(); // not enough arguments

?>

The following pattern are considered legit:

<?php

function x($a, $b, $c = 2) { 	return $a + $b; }
function y($a, $b, $c = 2) { 	return array_sum(func_get_args()); }
function z($a, ...$b) { 	return array_sum($b) + $a; }

x('a', 'b'); 

y('a', 'b', 'c', 'd'); 

z(1, 2, 3, 4); 

?>

Further Reading