I have now tested your example, @notrinos, and it doesn't work as intended.
I have now changed the function count_array($array) in /includes/ui/ui_globals.inc to this:

function count_array($array)
{
    return (is_array($array)) ? count($array) : (($array === NULL) ? 0 : 1);
}

and it works for PHP versions 7.2.12, 7.1.9, 7.0.23, 5.6.31, 5.5.25 and 5.4.10.

It gives the same return as the old count() without errors or warnings.
We only have to convert more counts() if we detect more errors. We can wait until next major to do this.

This has now been committed and a new file can be downloaded here:

/Joe.

Joe

function fa_count($input)
{
    if(is_array($input))
        return count($input);
    elseif(ctype_digit($input) && (int)$input > 0)
        return (int)$input;
    else
        return 0;
}

Do this we could change every curently count() to fa_count() without worry about errors that may arise somewhere.

your solution is working in this case but seems we still need a function to check both array element and number

The function is_positive_int doesn't work as you provide in php 7.2.

However changing

if (!is_positive_int($trans_no))
to
if (!trans_no)
do work.

what do you think?

joe

function is_positive_int($input)
{
    if(ctype_digit($input) && (int)$input > 0)
        return true;

    return false;
}

and line 371 of sales_db.inc needs to be modified to :

if (!is_positive_int($trans_no))

also roll back the last commit.

And I doubt this one also have logical error after this new commit.

Committed to stable repo. New file can be downloaded here.

Joe

    $a = 0; // Scalar
    $b = count($a);
    echo var_dump($b); // returns int(1)

    $a = array(); // Array
    $b = count($a);
    echo var_dump($b); // returns int(0)

Hence we should return a 1 if it is a scalar and not a 0!

In the old dispensation, the argument could be either an array or a scalar and the count() faithfully returned an acceptable result - was it a 0 or just false? In the current codebase, it will return a 0 if "it is a scalar" and also "even if it is an array and if the array has no elements".

Joe

I could have caught just one. May be this is affecting other places too.

Please rectify.