Bugfix in class-wp-translation-file-mo for "PHP Warning: Undefined array key 1 in"

[pander]

The warning "PHP Warning: Undefined array key 1 in" is flooding the error log file of my web service running WordPress.

I think the plugin that is the cause of this warning for me is ​https://github.com/qtranslate/qtranslate-xt/ or ​https://icalevents.com/ but I have seen it being reported for many different plugins.

Line 161 of wp-includes/l10n/class-wp-translation-file-mo.php is triggering this, is

<?php
list( $name, $value ) = array_map( 'trim', explode( ':', $meta_line, 2 ) );

To prevent the warning, I have changed line 157 from

<?php
if ( '' === $meta_line ) {

to

<?php
if ( '' === $meta_line || strpos($meta_line, ':') === false ) {

I know the warning is valid and should be fixed elsewhere, but my knowledge of WordPress is limited and this fix prevents that performance is impeded. Perhaps the warning should be caught in a different way, but this fixed it for now for me.

If there are way to pinpoint better what is causing this, please let me know. I can help to locate it but need some guidance.

[swissspidy]

Removing performance focus as this is not related to performance.

[swissspidy]

The fix sounds reasonable to me, it adds some hardening.

If there are way to pinpoint better what is causing this, please let me know. I can help to locate it but need some guidance.

One of your plugins has an invalid MO file. You can try a `var_dump( $this->file ) on line 160 to find the culprit.

Trac ticket: https://core.trac.wordpress.org/ticket/61794

Trac ticket: https://core.trac.wordpress.org/ticket/61794

@swissspidy Already opened #7115

[swissspidy]

In 58922:

I18N: Add hardening for invalid meta lines in MO files.

Props swissspidy, pander.
Fixes #61794.

https://core.trac.wordpress.org/changeset/58922

[pander]

Thanks. The culprit is

string(97) "/var/www/DOMAINNAME/wp-content/plugins/amr-ical-events-list/lang/amr-ical-events-list-nl_NL.mo"

and that was repeated 1142 times.

I regenerated the MO file with

cd /var/www/DOMAINNAME/wp-content/plugins/amr-ical-events-list/lang
mv amr-ical-events-list-nl_NL.mo /tmp
msgfmt amr-ical-events-list-nl_NL.po -o amr-ical-events-list-nl_NL.mo

and this fixed it.

[swissspidy]

#62097 was marked as a duplicate.