[Rejected] 1.8.33 upgrade and PHP 8 warnings

[HLFadmin]

I have successfully upgraded production forum to 1.8.33. Using PHP 7.4 without problems.
After cloning production server for testing purposes using PHP 8.0.27, I am going through and finding warnings. Most occur in plugins.

If I create a post containing a youtube video with a url in the form of https://youtu.be/YfdLh0MHqKw, I get the following messages.
Warning [2] Undefined array key "fragment" - Line: 1494 - File: inc/class_parser.php PHP 8.0.27 (Linux)
Warning [2] Undefined array key "query" - Line: 1505 - File: inc/class_parser.php PHP 8.0.27 (Linux)
Warning [2] Undefined array key 1 - Line: 1510 - File: inc/class_parser.php PHP 8.0.27 (Linux)
Warning [2] Undefined array key 0 - Line: 1587 - File: inc/class_parser.php PHP 8.0.27 (Linux)
Warning [2] Undefined array key "v" - Line: 1591 - File: inc/class_parser.php PHP 8.0.27 (Linux)

I note that line 1485 of inc/class_parser.php uses a native PHP function in the function mycode_parse_video() starting line 1470.
$parsed_url = @parse_url(urldecode($url));

The url does not contain a fragment in line 1494, or a query in line 1505, hence there are no $input keys in line 1510, unable to test the empty fragment array in 1587, as well as testing the $input array in 1591.

First, what purpose does line 1480 have? I think it is superfluous. Defined but not used.
1480 $bbdomain = parse_url($mybb->settings['bburl'], PHP_URL_HOST);

I made several modifications to the mycode_parse_video() function, although unable to post code in its entirety. Community only permits a single video per post, and cannot distinguish examples in comments.

Now, all three variations display.
youtu[dot]be/YfdLh0MHqKw
www[dot]youtube[dot]com/watch?v=YfdLh0MHqKw
www[dot]youtube[dot]com/watch#!v=YfdLh0MHqKw

I've had to obfuscate URLs used as explanation, including the ones used as examples in the code comments.

---

lines altered as below. By adding three lines, last two line numbers are pushed down.

1494 		if(array_key_exists('fragment', $parsed_url))	//core edit fixes error if no 'fragment' in $parsed_url
1499		if(array_key_exists('query', $parsed_url))	//core edit added to fix if no 'query' in $parsed_url
1500		{						//core edit added for if statement
1516		}						//core edit added for if statement
1590				if(isset($fragments[0]))	//core edit to fix when $fragments is empty
1594				elseif(isset($input['v']))	// core edit to fix when $input is empty

---

Continuing with checking the warnings. I intend all that I find to be documented in this thread.

If you are using a plugin which relies on PluginLibrary, you'll need to upgrade to an updated version.
Thanks to SvePu. https://community.mybb.com/thread-237593...pid1383414

---

When searching for Today's Posts
Warning [2] Undefined array key "lastread" - Line: 476 - File: search.php PHP 8.0.27 (Linux)
Warning [2] Undefined property: MyLanguage::$pages - Line: 2 - File: search.php(567) : eval()'d code PHP 8.0.27 (Linux)

The first is fixed in line 476 of search.php
Change

				if($thread['lastread'])

to

				if(isset($thread['lastread']))

[edited for correct logic]

				if(isset($thread['lastread']) && $thread['lastread'])

The second is apparently fixed by editing template forumdisplay_thread_multipage from

 <span class="smalltext">({$lang->pages} {$threadpages}{$morelink})</span>

to

 <span class="smalltext">({$threadpages}{$morelink})</span>

or by adding an element to search.lang.php

$l['pages'] = "Pages";

I stuck it in the blank line space at line 10 to maintain consistency with other MultiPage formats.

---

If you are using the absolutetime plugin by doylecc, which is fantastic already, you'll need to modify it so that it does not generate a warning under PHP 8.0 in ACP / Plugins page. If present, but not active, warning is given for undefined array key 'absolutetime'

Change

    if (absolutetime_is_installed()
        && is_array($plugins_cache)
        && is_array($plugins_cache['active'])
        && $plugins_cache['active']['absolutetime'] // this line errors
    ) {
        if (absolutetime_apply() !== true) {
            $absolutetime_info['description'] .= '<br /><span style="color:red; font-size:1.2em;">'
            .$lang->at_warn_core_edit.'</span>';
        }

to

	if (empty($plugins_cache) || !is_array($plugins_cache)) {
		$plugins_cache = $cache->read('plugins');
	}
	$active_plugins = $plugins_cache['active'];

    if (absolutetime_is_installed()
        && is_array($plugins_cache)
        && is_array($plugins_cache['active'])
        && !empty($active_plugins['absolutetime'])
    ) {
        if (absolutetime_apply() !== true) {
            $absolutetime_info['description'] .= '<br /><span style="color:red; font-size:1.2em;">'
            .$lang->at_warn_core_edit.'</span>';
        }

[HLFadmin]

I have moved the changes over to my production server and changed to PHP 8.0.27, and asked my forum members to identify any additional pages that display warning messages that I have not seen.

If I receive any reports, I will identify them here in this thread.

[HLFadmin]

Several warnings are generated when searching for keyword in posts, with fulltext search, displaying results as posts.

Undefined variable $inquote in lines 363, 381 and 487 in inc/functions_search.php
Using the same same logic as in other functions there, I have added a new line at 358

	$inquote = false;

Warning using array offset on value of type null in eval'd code generated from forum/search.php in line 983
That line evaluates forumdisplay_thread_gotounread template which calls for a value in $thread['newpostlink']
Following similar logic in other functions there, I have added a new line at 983

				$thread['newpostlink'] = get_thread_link($post['thread_lastpost']);

If the logic is incorrect, I'd hope someone with better programming skills would advise such and tell me why.
I'm approaching this endeavor as a learning opportunity.

edit to add:
There was a circumstance when displaying search results which generated a undefined array key 'sid' warning from forum/search.php in line 63.
edited to add explanation and correct fix:
A member used an old search as a bookmarked entry to return to the forum. The sid is expired.
Change line 63 from

	if(!$search['sid'])

to

	if(isset($search['sid']) && !$search['sid'])

This one works better.

	if(empty($search['sid']))

[HLFadmin]

When not mod and visible != 1

Undefined variable $status_type in eval'd code from inc/functions_post.php

Add line 787

$status_type='';

[HLFadmin]

In the process of troubleshooting a plugin, I am told there's a problem with inc/functions.php
I trust the source.

line #4591 of inc/functions.php within function get_attachment_icon() needs to be changed from:

    if($attachtypes[$ext]['icon'])
to
    if(!empty($attachtypes[$ext]['icon']))

[Eldenroot]

HLFadmin - what is valid? I will create a PR... thx!

[HLFadmin]

Easier to evaluate current error.log
When a warning occurs, I will start a new thread on each one.

Thank you for monitoring this forum.