Unexpected newline behavior in blade template with echo followed by verbatim

[Sjord]

Laravel Version

v11.4.0

PHP Version

8.3.6

Database Driver & Version

No response

Description

In a Blade template, when a echo expression is followed by a verbatim directive, zero or two newlines are echoed. It does not seem possible to echo one newline.

Steps To Reproduce

Input 1, with no newlines between {{ 1 }} and second line:

first line
{{ 1 }}@verbatim
second line
@endverbatim
final line

Output 1:

first line
1second line

final line

Input 2; one additional newline in the input results in two newlines between {{ 1 }} and second line in the output:

first line
{{ 1 }}
@verbatim
second line
@endverbatim
final line

Output 2:

first line
1

second line

final line

[Sjord]

{{ 1 }} is compiled into PHP code. The PHP end tag ?> gobbles up the following newline. To prevent this, Blade looks if the expression is followed by a newline, and injects two newlines after the PHP end tag. One is gobbled up by PHP, the other one is the original.

With @verbatim, the verbatim block is first replaced by a placeholder. Because the whole block including newlines is replaced by a fixed string, the {{ 1 }} expression is no longer followed by a newline. The compiler doesn't detect the newline and doesn't double it, so in the end result the newline is gobbled up by the PHP closing tag.

One way to solve this is to leave newlines alone in the input and always add a newline after a PHP closing tag, regardless of whether it is followed by a newline in the input.

E.g.

protected function compileRegularEchos($value)
{
    $pattern = sprintf('/(@)?%s\s*(.+?)\s*%s/s', $this->contentTags[0], $this->contentTags[1]);

    $callback = function ($matches) {
        $wrapped = sprintf($this->echoFormat, $this->wrapInEchoHandler($matches[2]));

        return $matches[1] ? substr($matches[0], 1) : "<?php echo {$wrapped}; ?>\n";
    };

    return preg_replace_callback($pattern, $callback, $value);
}

A workaround to get one newline is to put @verbatim on the same line as second line:

first line
{{ 1 }}
@verbatimsecond line
@endverbatim
final line

However, this is also unexpected, because there is no separator between @verbatim and second. This would not work for any other directive than verbatim.

[github-actions]

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If possible, please make a pull request fixing the issue you have described, along with corresponding tests. All pull requests are promptly reviewed by the Laravel team.

Thank you!

[driesvints]

Thanks @Sjord. Would love a PR that could improve this one.

[Sjord]

One way to solve this is to leave newlines alone in the input and always add a newline after a PHP closing tag

I looked further into this, and there are two problems with this solution:

• The current implementation uses the same newline style as the input. It uses \r\n if the input uses \r\n. Hardcoding a newline after the end tag would break that.
• There are several unit tests that assert that compiling a variable results in <?php ... ?> without newline. This is easily solvable, but not so elegant.

Another possible solution is to move whitespace in front of the verbatim block:

    protected function storeVerbatimBlocks($value)
    {
        return preg_replace_callback('/(?<!@)@verbatim(\s*)(.*?)@endverbatim/s', function ($matches) {
            return $matches[1] . $this->storeRawBlock($matches[2]);
        }, $value);
    }