Bug: set_checkbox() default value not working

[NSURLSession0]

Describe the bug
The default value in the set_checkbox($field[, $value = ''[, $default = FALSE]]) method is not used. When writing:

var_dump(set_checkbox('field', 'value', true)); 

It prints:
'' (length=0)

This bug was already reported earlier (#3228), but should have been fixed by (#3229). It seems the fix is no longer working.

CodeIgniter 4 version
4.1.1

Affected module(s)
Which package or class is the bug in, if known.

Expected behavior, and steps to reproduce if appropriate
I expect the code above to result in 'true' as 'field' is not set in $_POST.

Context

• OS: MacOS
• Web server Apache 2.4.46
• PHP version 7.4.12

[NSURLSession0]

Oops, this issue was caused by my own code. I am setting post-data manually using $this->request->setGlobal('post', $data)). This way placeholders in custom validation rules will be filled in with my data.
Because I manually set post data, the post data array is never empty and a different path is used in form_helper.php.

I fixed this issue by only setting the custom post data when the request method is actually 'post'.