[php 8.1] preg_split(): Passing null to parameter #3 ($limit) of type int is deprecated

[codebymikey]

Feature Request

There's an unhandled PHP 8.1 deprecation scenario with preg_split that's currently not handled.

Example https://3v4l.org/cVPim

I guess we need something similar to NullToStrictStringFuncCallArgRector but for integers.

Diff

Proposed change should be to convert the NULL to a -1.

$output = "a  b\n\nc";
-var_dump(preg_split('/\s/', $output, NULL, PREG_SPLIT_NO_EMPTY));
+var_dump(preg_split('/\s/', $output, -1, PREG_SPLIT_NO_EMPTY));
$limit = null;
-var_dump(preg_split('/\s/', $output, $limit, PREG_SPLIT_NO_EMPTY));
+var_dump(preg_split('/\s/', $output, (int) $limit, PREG_SPLIT_NO_EMPTY));

[samsonasik]

what the different between pass -1 and 0?

using cast (int) NULL result 0 if we are going to using cast for similar transform

[samsonasik]

Reading documentation, it seems pass 0 or -1 is equal:

limit
----

    If specified, then only substrings up to limit are returned with the rest of the string being placed in the last substring. A limit of -1 or 0 means "no limit".

so, it seems similar logic can be used for the new rule to use cast int for defined functions.

could you create PR? Thank you

[TomasVotruba]

@samsonasik Could you add a rule for this one as well? 👍 Should be part of PHP 8.1 set

[samsonasik]

I will try

[samsonasik]

I created PR:

• https://github.com/rectorphp/rector-src/pull/7240

for it.