Introduce WP_User::has_prop_val() magic method

[wpsmith]

When using WP_User::has_prop( $key ), I believe the expectation is that if the property has a value, it would return true. However, it is returning true if the key is set or if the key exists. So if one uses it like WP_User::has_prop( 'user_url' ), it returns true regardless, simply because that's a standard WordPress user field.

So, keeping that functionality for checking even custom properties, I thought it may be beneficial to add a magic method for checking whether a property is set ( WP_User::has_prop( $key ) ) and has a value ( WP_User::get( $key ) ).

Thus, this ticket desires to add two methods: has_prop_val() & __hasval()

[scribu]

Magic methods aren't something you can arbitrarily create. They're a predefined set of special constructs in the PHP language. __hasval() is not one of them: ​http://php.net/manual/en/language.oop5.magic.php

[scribu]

This comes down to an inconsistency in PHP, where __isset() is called by both isset() and empty():

$user->user_url = '';

isset( $user->user_url );   // true
!empty( $user->user_url );  // false

For explicit calls, you have to be more verbose:

$user->user_url = '';

$user->has_prop( 'user_url' );  // true
$user->has_prop( 'user_url' ) && !empty( $user->get( 'user_url' );  // false

So, has_prop_val() sort of makes sense, but drop __hasval().

[scribu]

Actually, since get() doesn't throw a notice for undefined properties, you could just do this:

$value = $user->get( 'user_url' );

if ( !empty( $value ) ) {
  ...
}

[wpsmith]

Makes sense. Thanks!

[nacin]

!empty( $user->get( 'user_url' ) ) won't work because it's not a variable, but you can just drop the empty() call.

if ( $user->get( 'user_url' ) )