It seems the square brackets are the problem. 'Y-m-d\TH:i:sP e' works fine. https://3v4l.org/LJlNJ

https://3v4l.org/4bcK8 clarifies; the timezone would be [Europe/Berlin].

Europe/Berlin] actually, probably. I'm assuming the parser just doesn't stop on ]. https://3v4l.org/PVnac

Ah, right, @iluuu1994! Fixing exactly this issue would be trivial:

 ext/date/lib/parse_date.re | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/date/lib/parse_date.re b/ext/date/lib/parse_date.re
index 403f98d5ea..c2cdbc483b 100644
--- a/ext/date/lib/parse_date.re
+++ b/ext/date/lib/parse_date.re
@@ -754,7 +754,7 @@ static timelib_long timelib_lookup_abbr(const char **ptr, int *dst, char **tz_ab
 	timelib_long  value = 0;
 	const timelib_tz_lookup_table *tp;
 
-	while (**ptr != '\0' && **ptr != ')' && **ptr != ' ') {
+	while (**ptr != '\0' && **ptr != ')' && **ptr != ' ' && **ptr != ']') {
 		++*ptr;
 	}
 	end = *ptr;

Anyhow, this is a timelib issue, but I don't think we need to report upstream, since @derickr is the ext/date maintainer as well.

It is a documentation problem DateTime::createFromFormat accepts the datetime string but is valid on the user side if the format is not repeated more than once, "p" and "e" or "e" and "e" is a repeat. Because the date to be created must be valid

<?php

var_dump(DateTime::createFromFormat('Y-m-d\TH:i:sP e e', '2022-02-18T00:00:00+23:00 Europe/Berlin Europe/Rome'));
var_dump(var_dump(DateTime::GetLastErrors()));

?>

Expected Result is Europe/Rome not Europe/Berlin or +23:00 (For me output date Expected is timezone: T from ISO 8601 , without Europe/Berlin or Europe/Rome ex1. 2022-02-17T23:00:00 or ex2. 2022-02-18T00:00:00+01:00)

This bug:

<?php

$date = DateTime::createFromFormat('Y-m-d H:i:s \[e\]', '2022-02-18 00:00:00 [Europe/Berlin]');
var_dump($date, is_object($date) ? $date->format('U') : NULL, is_object($date) ? $date->getOffset() : NULL);
var_dump(var_dump(DateTime::GetLastErrors()));

?>

It would be better to create a new format, instead of validating the final part of a string with the rest of the string
Special format: DateTimeImmutable::createFromFormat, date_create_immutable_from_format, DateTime::createFromFormat
and date_create_from_format: output date default hide, esplicit show: DateTimeInterface::format, DateTimeImmutable::format, DateTime::format
and date_format (function format) 'Y-m-d\TH:i:s output date[e output date]';

This is fixed in timelib now — I'll release and then merge this into PHP before the release of 8.0.26 and 8.1.13

derickr/timelib@cca0fe4

Now fixed, for PHP 8.1.14 and PHP 8.2.1.