StringHelper::truncate(null, 10) causes error - userland fix

[cgsmith]

What steps will reproduce the problem?

Create a StringHelper::truncate() call to a null property. Quick note: I don't think that this is a framework issue and think it is more userland code but wanted to open the issue in case someone else receives the error.

I solved it by wrapping the helper function in a userland check:

What is the expected result?

Was expecting an upgrade to 8.1 to go smoothly. I had to change a few things in the user code to make this work. Not sure if documentation should be updated to note this? If not feel free to close this issue.

What do you get instead?

Deprecated: mb_strlen(): Passing null to parameter #1 ($string) of type string is deprecated

Additional info

Error:

yii\base\ErrorException: mb_strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /app/vendor/yiisoft/yii2/helpers/BaseStringHelper.php:132

Q	A
Yii version	2.0.47
PHP version	8.1
Operating system	Docker yii2 container

[samdark]

I think we may add a null-check there for convenience. @bizley, @rob006 what do you think?

[rob006]

What it should return in case of null? For grid/list view returning null would be more practical, but IMO it is weird to return null in methods for string processing.

[cgsmith]

I do have a draft with a null check but didn't want to do too much work without checking with you. I have some new tests as well written for null passed to ::truncate and the other functions.

Can we set the data type to string on the first parameter for this call and similar calls or will it break B/C?

[bizley]

If we add null check for convenience , shouldn't we add it everywhere where we denied change because the docs are not allowing null to be passed?

[InsaneSkull]

What it should return in case of null? For grid/list view returning null would be more practical, but IMO it is weird to return null in methods for string processing.

May be empty string '' as per default method return type.

Not sure about going strict type. truncate expects string parameter.

[cgsmith]

If truncate expects a string parameter shouldn't we enforce the type on the parameter?

[bizley]

I would add the null-checks everywhere (since we cannot do the arguments type-forcing), I'm just mentioning that because we used to argue that since the docs are not allowing null (like with StringHelper::truncate) we should not do any checks and make it a developer's issue.

[terabytesoftw]

Checking for nulls everywhere will make it compatible beyond 8.2, but the docs are based on when they were created, now the language is moving forward, adding more type checking and the framework needs to move along with the language.

[cgsmith]

I agree that this is a developer issue - I just wanted the issue opened because the error was a little harder to troubleshoot between 8.0 and 8.1.

Curious @bizley why type forcing can't be done on the arguments?

[bizley]

It's because we are still supporting PHP 5.4.

[rob006]

now the language is moving forward, adding more type checking and the framework needs to move along with the language.

Accepting null here and silently treating it as empty string is reverting progress made by language. On the other hand checking for null and throwing more verbose exception will add some additional overhead without much of a gain (you will still get an exception, just with different message).

[bizley]

you will still get an exception, just with different message

I prefer controlled flow.

[lubosdz]

Any reason why $string cannot be simply checked inside function ? e.g.
$string = trim($string) or casted $string = (string) $string

[bizley]

Yes, for cases where an argument should be a string we could do that (and we do in many places). The null check should be for the multi-types arguments.

[wartur]

I think this is same history in Yii2 Gii ActiveRecords model generator

==================================================Running 'Model Generator'...

PHP Deprecated Warning 'yii\base\ErrorException' with message 'trim(): Passing null to parameter #1 ($string) of type string is deprecated'

in /var/www/html/vendor/yiisoft/yii2/validators/FilterValidator.php:81

Stack trace:
#0 [internal function]: yii\base\ErrorHandler->handleError(8192, 'trim(): Passing...', '/var/www/html/v...', 81)
#1 [internal function]: trim(NULL)
#2 /var/www/html/vendor/yiisoft/yii2/validators/FilterValidator.php(81): call_user_func('trim', NULL)
#3 /var/www/html/vendor/yiisoft/yii2/validators/Validator.php(260): yii\validators\FilterValidator->validateAttribute(Object(yii\gii\generators\model\Generator), 'queryClass')
#4 /var/www/html/vendor/yiisoft/yii2/base/Model.php(368): yii\validators\Validator->validateAttributes(Object(yii\gii\generators\model\Generator), Array)
#5 /var/www/html/vendor/yiisoft/yii2-gii/src/console/GenerateAction.php(35): yii\base\Model->validate()
#6 [internal function]: yii\gii\console\GenerateAction->run()
#7 /var/www/html/vendor/yiisoft/yii2/base/Action.php(93): call_user_func_array(Array, Array)
#8 /var/www/html/vendor/yiisoft/yii2/base/Controller.php(178): yii\base\Action->runWithParams(Array)
#9 /var/www/html/vendor/yiisoft/yii2/console/Controller.php(180): yii\base\Controller->runAction('model', Array)
#10 /var/www/html/vendor/yiisoft/yii2/base/Module.php(552): yii\console\Controller->runAction('model', Array)
#11 /var/www/html/vendor/yiisoft/yii2/console/Application.php(180): yii\base\Module->runAction('gii/model', Array)
#12 /var/www/html/vendor/yiisoft/yii2/base/Controller.php(212): yii\console\Application->runAction('gii/model', Array)
#13 /var/www/html/commands/ExecController.php(94): yii\base\Controller->run('gii/model', Array)
#14 [internal function]: app\commands\ExecController->actionGar()
#15 /var/www/html/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
#16 /var/www/html/vendor/yiisoft/yii2/base/Controller.php(178): yii\base\InlineAction->runWithParams(Array)
#17 /var/www/html/vendor/yiisoft/yii2/console/Controller.php(180): yii\base\Controller->runAction('gar', Array)
#18 /var/www/html/vendor/yiisoft/yii2/base/Module.php(552): yii\console\Controller->runAction('gar', Array)
#19 /var/www/html/vendor/yiisoft/yii2/console/Application.php(180): yii\base\Module->runAction('exec/gar', Array)
#20 /var/www/html/vendor/yiisoft/yii2/console/Application.php(147): yii\console\Application->runAction('exec/gar', Array)
#21 /var/www/html/vendor/yiisoft/yii2/base/Application.php(384): yii\console\Application->handleRequest(Object(yii\console\Request))
#22 /var/www/html/yii(19): yii\base\Application->run()
#23 {main}

[tomaszkane]

It's because we are still supporting PHP 5.4.

@bizley Why? I think I know but would like to make sure.

[bizley]

I think it was a promise made by the original team.

[My6UoT9]

https://github.com/yiisoft/yii2#installation

The minimum required PHP version of Yii is PHP 5.4.

[tomaszkane]

I think it was a promise made by the original team.

OK. Keeping promises is very good. But today 5.4 is dead: https://stitcher.io/blog/php-version-stats-january-2023

Do Yii2 team has any statistic how many installation (updates) is made from hosts with old PHP versions?
Is keeping support for this promile of users worth keeping Yii2 core outdated?

@samdark

[schmunk42]

Some stats: https://packagist.org/packages/yiisoft/yii2/php-stats

If 5.4 is dropped an ie. 7.4 is the new minimum, I'd strongly advocate for a 2.1.0 version.

[lubosdz]

PHP 7.0 might pass tests.

[samdark]

1. We can drop PHP 5.4 but I'd make it Yii 2.1 then as @bizley suggested.
2. Type-forcing for Yii2 might be very troublesome. That's big amount of work and unless either someone performs it and sends a PR or sponsors one of the team memers to do it, I don't think it is worth focusing on.

[samdark]

For current code I'd add checks everywhere.

[My6UoT9]

As far as I know, With PHP 8.2 and JIT types will improve performance, before that it does not, and in many cases will be slower as it now has to type check. I am not entirely sure if PHP 8.2 brings those benefits.
https://stackoverflow.com/a/32943651/5542121

While I am for making PHP 8.x the minimum required version, its not like PHP 5.4 is not used. But these might be just automated testing systems.
PHP 7 is actually already unsupported https://www.php.net/supported-versions.php
https://w3techs.com/technologies/history_details/pl-php/5

[bizley]

Let's continue discussion about 2.1 here #19831

Here let's focus on the issue only please.

[uaoleg]

I did a fix: #19833