property.abstract

Code example

<?php declare(strict_types = 1);

class Foo // ERROR: Non-abstract classes cannot include abstract properties.
{
	abstract public int $value { get; }
}

Why is it reported?

PHP does not allow abstract properties in non-abstract classes. An abstract property declares a hook (like get or set) without providing an implementation, which means subclasses must provide the implementation. This only makes sense in abstract classes, where subclasses are required to implement the missing parts.

This is a PHP language-level restriction enforced since PHP 8.4, which introduced property hooks.

How to fix it

Either make the class abstract:

 <?php declare(strict_types = 1);

-class Foo
+abstract class Foo
 {
 	abstract public int $value { get; }
 }

Or provide a body for the property hook:

 <?php declare(strict_types = 1);

 class Foo
 {
-	abstract public int $value { get; }
+	public int $value {
+		get => $this->value;
+	}
 }