Ignore null values in subform rule

[laoneo]

Summary of Changes

The subform rule can get null as value to validate. This throws the following warning:
Warning: foreach() argument must be of type array|object, null given in /var/www/html/j3/libraries/src/Form/Rule/SubFormRule.php on line 52

@Fedik can you help here with a test case in core?

Testing Instructions

• Add the following code to the file modules/mod_custom/mod_custom.xml after line 27:

<field type="subform" name="subform" multiple="true" label="subform" 
  validate="subform" filter="unset">
  <form>
    <field type="text" name="text" label="text" />
  </form>
</field>

• Create a new custom module and save it

Actual result BEFORE applying this Pull Request

The warning mentioned above is added to the logs of the server.

Expected result AFTER applying this Pull Request

No Warning.

[Fedik]

@laoneo do you have a default value for subform field?

[Fedik]

the error probably because of wrong JSON in default value :

joomla-cms/libraries/src/Form/Field/SubformField.php

Lines 445 to 456 in 9bd9e52

	// Subform field may have a default value, that is a JSON string
	if ($value && is_string($value))
	{
	$value = json_decode($value, true);
	// The string is invalid json
	if (!$value)
	{
	return null;
	}
	}

you can get this error with this field:

<field type="subform" name="subform" multiple="true" label="subform" 
  validate="subform" default="{'blabla', 'bad json'}">
  <form>
    <field type="text" name="text" label="text" />
  </form>
</field>

[laoneo]

No default value. The problem is that I do an filter="unset" before. So it is really NULL as value.

[laoneo]

The test function needs to return true or false.

[Fedik]

The problem is that I do an filter="unset" before. So it is really NULL as value.

okay, I not sure we have it in core, but such may be used in other extensions also
then maybe this:

Place it in mod_custom:

<field type="subform" name="subform" multiple="true" label="subform" 
  validate="subform" filter="unset">
  <form>
    <field type="text" name="text" label="text" />
  </form>
</field>

Add dump($value);exit; before return here:

joomla-cms/libraries/src/Form/Rule/SubformRule.php

Lines 86 to 88 in 368a1f3

	}
	return true;

And try save the module,
Before : you will get warning, then dump result;
After: only dump result

[laoneo]

Ok thanks, updated the testing instructions.

[Fedik]

I have tested this item ✅ successfully on 6a9ebdc

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[chmst]

I have tested this item ✅ successfully on 6a9ebdc

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_{This comment was created with the J!Tracker Application at issues.joomla.org/tracker/joomla-cms/34585.}

[chmst]

RTC

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[HLeithner]

Thanks!