PHP 7.4 Notice: Trying to access array offset on value of type null

A different approach to patch the current issue. Should be more consistent to current behaviour.

Patch updated.

I don't think the is_array($conditional_component) is needed.

Please put the fix into an issue fork.

@Lian: Thanks for evaluating this.

The variable $conditional_component is created on line 2078:

$conditional_component = isset($component['extra']['conditional_component']) && isset($node->webform['components'][$component['extra']['conditional_component']]) ? $node->webform['components'][$component['extra']['conditional_component']] : NULL;

Logically speaking, the variable can be NULL instead of an array. And evaluating isset($array['key']), if $array is null, could raise "Unidentified Index with NULL value" warning in some PHP setup. So is_array($conditional_component) is a safety check before evaluating isset($conditional_component['cid']).

isset($conditional_component['cid']) will be FALSE even when the value of $conditional_component is NULL. It won't also raise any exception, or cause errors.

You can verify that with this code, which prints 0.

$array = NULL;
$test = (integer) isset($array["ggg"]);
echo $test, "\n";

@kiamlaluno: Just tested. You are right. Since isset is a language construction, it does not evaluate the function parameter. So it does not trigger the warning. Just added a new patch (and a new commit to the issue fork) to simplify the code.

Thanks.

The error shown in the dispatcher isn't much descriptive.

09:49:17 error: patch failed: webform.module:2076
09:49:17 error: webform.module: patch does not apply
09:49:17 Patch Error
09:49:17 The patch attempt returned an error. Error code: 1
09:49:17 Patch Failed to Apply
09:49:17 error: patch failed: webform.module:2076
09:49:17 error: webform.module: patch does not apply

Maybe should squash the commits into a single patch. This system is quite confusing.

Please put the patch into the issue fork. Let me know if you need help doing this.

I have squashed the patch both here and on the issue fork. Please check.