Functions inspecting arguments report the current parameter value

PHPCompatibility Code

PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection

Explanation

Since PHP7.0 func_get_arg(), func_get_args(), debug_backtrace() and exception backtraces have started reporting the current value of a parameter. When analysing your files, PHPCompatibility might not be able to determine if a parameter has been modified. To avoid missing cases where the value would have changed, all occurrences where a parameter is touched will be reported for manual inspection.

Recommendation

Manually inspect warnings. Fix problematic usages. Use phpcs:ignore for the remaining false positives.

Example That Requires Fixing

function myFunction($email) {
    $email = trim($email);
    saveEmail($email);
    return func_get_arg(0);
}

If the intent was to return the original value of $email that was passed to the function, then you will need to fix the logic:

function myFunction($email) {
    $newEmail = trim($email);
    saveEmail($newEmail);
    return func_get_arg(0);
}

What we did here is avoid overriding the value of $email, so that it would still be possible to return the original value, maintaining the intended behavior of the code. We could also take the opportunity to get rid of func_get_arg and return $email directly, as the use of func_get_arg is not necessary in this context.

Example That Should Be Ignored

function myFunction($name) {
    log($name);
    debug_backtrace();
}

There is nothing to fix here, yet it will still be reported as a warning by PHPCompatibility.

The following comment is an annotation allowing you to ignore a line or a specific sniff. Here we are specifying that we want to ignore the sniff by its name:

// phpcs:ignore PHPCompatibility.FunctionUse.ArgumentFunctionsReportCurrentValue.NeedsInspection
function myFunction($name) {
    log($name);
    debug_backtrace();
}