Strange string concatenation issue after upgrading to PHP 8.3

[janforth]

Description

In PHP 8.2 this line worked perfectly well:

$togetherWithName = "gemeinsam mit " . (($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly()) ? ($article?->getAuthor()?->getFullName() ?? "N.N.") : ($article?->getCoAuthor()?->getFullName() ?? "N.N.");

After upgrading to PHP 8.3 the string concatenation did not work anymore. The first part of string "gemeinsam mit " (engl.: 'together with') was always left out for whatever reason. The string $togetherWithName always only contained the name of the respective author from the right party of the string concatenation.

This could fix the issue:

            $togetherWithName = (($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly()) ? ($article?->getAuthor()?->getFullName() ?? "N.N.") : ($article?->getCoAuthor()?->getFullName() ?? "N.N.");
            $togetherWithName = "gemeinsam mit " . $togetherWithName;

But I think the one-liner should work.

Thanks!

PHP Version

PHP 8.3

Operating System

Debian 12

[heiglandreas]

$togetherWithName = "gemeinsam mit " . (($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly()) ? ($article?->getAuthor()?->getFullName() ?? "N.N.") : ($article?->getCoAuthor()?->getFullName() ?? "N.N.");

The trouble is probably that the whole string gets separatet into the following construct:

if ("gemeinsam mit " . (($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly())) {
    $togetherWithName = ($article?->getAuthor()?->getFullName() ?? "N.N.");
} else {
    $togetherWithName = ($article?->getCoAuthor()?->getFullName() ?? "N.N.");
}

Having everything in one line might be amazing. But definitely hinders readability. And by that also figuring our what actually happens where.

[janforth]

Point taken! ;)

[SVGAnimate]

@janforth are you using the mbstring extension?

[heiglandreas]

An option to still use this in one line would be to add some more braces:

 $togetherWithName = "gemeinsam mit " . ((($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly()) ? ($article?->getAuthor()?->getFullName() ?? "N.N.") : ($article?->getCoAuthor()?->getFullName() ?? "N.N."));

Note the added opening brace after the first dot and the added closing brace before the semicolon. That makes sure that the string concatenation happens after the big chunk has been treated as one trinary operator.

Otherwise the string concatenation is seen as part of the test of the trinary operation.

And according to https://3v4l.org/Sg1rI I'd question that it actually worked in PHP8.2 the way you expected it to work... 🙈

[janforth]

@janforth are you using the mbstring extension?
@SVGAnimate I do.

[janforth]

@heiglandreas Thanks for shedding some light on this. It clears things up. Obviously I misjudged the binding effect of the dot in the order of operations. But I can tell you: It definitely worked in PHP 8.2.

[heiglandreas]

@janforth: Can you create a case on 3v4l.org (or a similar tool) that reproduces what you see in PHP8.2 as well as in PHP8.3? That would be really helpful for this case to understand where the problem arises.

[SVGAnimate]

Without using mbstring it seems to work on PHP-8.3.1.

can you show how you use the mb_* functions

class Context {
    function isForCoAuthorOnly() {
        return false;
    }
}
class Author {
    protected $name;
    protected $email;
    function __construct($name, $email) {
        $this->name = $name;
        $this->email = $email;
    }
    function getEmail() {
        return $this->email;
    }
    function getFullName() {
        return $this->name;
    }
}

class Article{
    protected $coAuthor;
    protected $author;
    function __construct($author, $coAuthor) {
        $this->coAuthor = $author;
        $this->author = $coAuthor;
    }
    function getCoAuthor() {
        return $this->coAuthor;
    }
    function getAuthor() {
        return $this->author;
    }
}

$article = new Article(new Author("John", "[email protected]"), new Author("Doe", "[email protected]"));
$emailContext = new Context();

$receiver=["foo"];
$coautor = "John Doe";

// 
$togetherWithName = "gemeinsam mit " . (($receiver[0] === ($article?->getCoAuthor() ?? "none") || $receiver[0] === ($article?->getCoAuthor()?->getEmail() ?? "none" ) || $coautor) || $emailContext->isForCoAuthorOnly()) ? ($article?->getAuthor()?->getFullName() ?? "N.N.") : ($article?->getCoAuthor()?->getFullName() ?? "N.N.");

var_dump($togetherWithName);

@janforth Can you provide a simplified version of your code and the problematic datasets?
And also, can you indicate the encoding of your php file

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