As we discussed, there are multiple ways to achieve the original functionality of count() and not emit an E_WARNING.
In PHP 7.3 a new function was added is_countable, specifically to address the E_WARNING issue and the prevalence of applications adopting is_array($var) || $var instanceof \Countable in their code.
In PHP 7.2, a Warning was added while trying to count uncountable
things. After that, everyone was forced to search and change their
code, to avoid it. Usually, the following piece of code became
standard:
if (is_array($foo) || $foo instanceof Countable) {
// $foo is countable
}
https://wiki.php.net/rfc/is-countable
Custom Function Replacement
For that reason it seems the best method of resolving the issue, is to perform the same functionality that PHP is doing with is_countable and creating a custom function to ensure compliance with the original functionality of count.
Example https://3v4l.org/8M0Wd
function countValid($array_or_countable, $mode = \COUNT_NORMAL)
{
if (
(\PHP_VERSION_ID >= 70300 && \is_countable($array_or_countable)) ||
\is_array($array_or_countable) ||
$array_or_countable instanceof \Countable
) {
return \count($array_or_countable, $mode);
}
return null === $array_or_countable ? 0 : 1;
}
Result
array: 3
string: 1
number: 1
iterator: 3
countable: 3
zero: 1
string_zero: 1
object: 1
stdClass: 1
null: 0
empty: 1
boolt: 1
boolf: 1
Notice: Undefined variable: undefined in /in/8M0Wd on line 53
undefined: 0
Shim is_countable() function
Using the above replacement function, it is also possible to shim is_countable in PHP <= 7.2, so it is only used when needed, with minimal overhead.
Example https://3v4l.org/i5KWH
if (!\function_exists('is_countable')) {
function is_countable($value)
{
return \is_array($value) || $value instanceof \Countable;
}
}
function countValid($array_or_countable, $mode = \COUNT_NORMAL)
{
if (\is_countable($array_or_countable)) {
return \count($array_or_countable, $mode);
}
return null === $array_or_countable ? 0 : 1;
}
Ignore count() Warnings
As the functionality of count() has not changed and not did not typically emit warnings in the past. An alternative to using a custom function, is to ignore the warning outright by using the @ Error Control Operator
Warning: This approach has the impact of treating undefined variables as NULL and not displaying Notice: Undefined variable:
message.
Example https://3v4l.org/nmWmE
@count($var);
Result
array: 3
string: 1
number: 1
iterator: 3
countable: 3
zero: 1
string_zero: 1
object: 1
stdClass: 1
null: 0
empty: 1
boolt: 1
boolf: 1
---
Undefined: 0
Replace count() using APD extension
As for replacing the internal PHP function count(). There is a PECL extension APD (Advanced PHP Debugger), that allows for override_function that works on core PHP functions. As the extension name suggests, it is technically meant for debugging, but is a viable alternative to replacing all instances of count for a custom function.
Example
\rename_function('count', 'old_count');
\override_function('count', '$array_or_countable,$mode', 'return countValid($array_or_countable,$mode);');
if (!\function_exists('is_countable')) {
function is_countable($value)
{
return \is_array($value) || $value instanceof \Countable;
}
}
function countValid($array_or_countable, $mode = \COUNT_NORMAL)
{
if (\is_countable($array_or_countable)) {
return \old_count($array_or_countable, $mode);
}
return null === $array_or_countable ? 0 : 1;
}
