Kaos 55.1 - E_WARNING: Undefined array key 0 about dokuwiki

[fiwswe]

The root cause seems to be that some plugin apparently has some weird/illegal data in its …/conf/metadata.php file.

$meta is assumed to be an array of key => value tuples with each value being an array with at least one element. See Configuration Metadata

Which plugins do you have installed?
And which one does not conform to the defined standard?

However

dokuwiki/lib/plugins/config/core/Loader.php

Line 216 in 4c1ed9d

if ($value[0] == 'fieldset') continue; //plugins only get one fieldset

could be more tolerant here. For example like this:

            if (($value[0] ?? null) == 'fieldset') continue; //plugins only get one fieldset

[fiwswe]

PS. It could also be an installed template, not a plugin.

[Zweihorn]

May be linked to #4193 (comment)

[Zweihorn]

THX @fiwswe

Culprit found as the template sprintdoc in lib/tpl/sprintdoc/conf/metadata.php last line as follows:

<?php

$meta['sidebar_sections'] = array(
                                'multichoice',
                                '_choices' => array(
                                    'h1',
                                    'h1,h2',
                                    'h1,h2,h3,h4,h5',
                                    'li.level1 > .li',
                                ),
                            );

$meta['header_layout'] = array(
                            'multichoice',
                            '_choices' => array(
                                'header-default',
                                'header-compact',
                            ),
                        );

$meta['autocollapse'] = array('onoff');
$meta['closedwiki'] = array('onoff');
$meta['copyright'] = [];

After changing the last line to $meta['copyright'] = array(''); there is no warning in the log file. The "Configuration Settings" page works without issue and shows the intended behaviour with the "tpl»sprintdoc»copyright" setting.

The a.m. syntax change is in accordance with https://www.dokuwiki.org/devel:configuration#classes and provides a "Default class ('setting'), textarea" definition. This avoids the 'null' reference and should meet the expectations.

Voila.

[Zweihorn]

NB

A change to $meta['copyright'] = ['']; could be sufficient but I prefer a syntax in accordance with the https://www.dokuwiki.org/devel:configuration#classes definitions. Thus $meta['copyright'] = array(''); as above.

[Zweihorn]

This is a bug of the a.m. template and this PR can be closed.