Incorrect scope matching when arrow function used inside IF condition

[snapshotpl]

I run phpcs with slevomat/coding-standard and I get error:

Fatal error: Uncaught PHP_CodeSniffer\Exceptions\RuntimeException: Undefined index: scope_closer in /var/www/vendor/slevomat/coding-standard/SlevomatCodingStandard/Helpers/UseStatementHelper.php on line 195 in /var/www/vendor/squizlabs/php_codesniffer/src/Runner.php:606
Stack trace:
#0 /var/www/vendor/slevomat/coding-standard/SlevomatCodingStandard/Helpers/UseStatementHelper.php(195): PHP_CodeSniffer\Runner->handleErrors(8, 'Undefined index...', '/var/www/vendor...', 195, Array)
#1 /var/www/vendor/slevomat/coding-standard/SlevomatCodingStandard/Helpers/UseStatementHelper.php(137): SlevomatCodingStandard\Helpers\UseStatementHelper::getUseStatementPointers(Object(PHP_CodeSniffer\Files\LocalFile), 0)
#2 /var/www/vendor/slevomat/coding-standard/SlevomatCodingStandard/Sniffs/Namespaces/UselessAliasSniff.php(40): SlevomatCodingStandard\Helpers\UseStatementHelper::getFileUseStatements(Object(PHP_CodeSniffer\Files\LocalFile))
#3 /var/www/vendor/squizlabs/php_codesniffer/src/Files/File.php(496): SlevomatCodingStandard\Sniffs\Names in /var/www/vendor/squizlabs/php_codesniffer/src/Runner.php on line 606

This is code which causes error:

<?php

class MyClass
{
    public function __construct() {
        if (
            $this->valid(fn(): bool => 2 > 1)
        ) {

        }
    }

    private function valid(callable $callable): bool
    {
        return $callable();
    }
}

First reported here slevomat/coding-standard#902

[kukulich]

I was able to prepare a workaround but I suppose that T_CLASS token should have scope_opener and scope_closer.

slevomat/coding-standard@4c88f6c

[jrfnl]

Confirmed. But there's more going on here: the T_COLON for the return type of the fn arrow function within the if condition is being seen as the scope opener for the if.

I have a feeling that's what's throwing everything off.

The check for scope openers for control structures using alternative syntax should probably make sure that the close parenthesis of the control structure's open parenthesis has been seen before looking for a scope opener.

[gsherwood]

I think this is going to require the arrow function detection code to be moved out of processAdditional and into the main process method.

[gsherwood]

I think this is going to require the arrow function detection code to be moved out of processAdditional and into the main process method.

Much much easier said than done. Probably need to figure something else out.

[gsherwood]

Looks like it's easier to just ensure that a scope opener has the same nested parenthesis as the scope condition. So in this case, the T_COLON is nested differently to the T_IF, so it can't be the scope opener for it.

[gsherwood]

I've pushed up a fix for this issue and PHPCS is now matching the scope openers and closers correctly for the code sample. If you get a chance to test, please let me know if there are other code snippets where this doesn't work. Thanks for the report.