nullCoalesce.initializedProperty - Phpstan

Code example

php

<?php declare(strict_types = 1);

class User
{
	private string $name;

	public function __construct()
	{
		$this->name = 'John';
	}

	public function doFoo(): void
	{
		echo $this->name ?? 'default'; // ERROR: Property User::$name on left side of ?? is not nullable and initialized.
	}
}

Why is it reported?

The ?? (null coalescing) operator is designed to provide a fallback value when the left side is null or undefined. In this case, PHPStan has determined that the property being checked with ?? has a non-nullable native type and is guaranteed to be initialized at the point of access. Since the property can never be null and is always initialized, the right side of ?? will never be used, making the null coalescing operator redundant.

How to fix it

Remove the null coalescing operator since the property is always initialized and non-nullable:

diff-php

 <?php declare(strict_types = 1);

 class User
 {
 	private string $name;

 	public function __construct()
 	{
 		$this->name = 'John';
 	}

 	public function doFoo(): void
 	{
-		echo $this->name ?? 'default';
+		echo $this->name;
 	}
 }

Or if the property should legitimately be nullable, change its type:

diff-php

 <?php declare(strict_types = 1);

 class User
 {
-	private string $name;
+	private ?string $name;

 	public function __construct()
 	{
 		$this->name = 'John';
 	}

 	public function doFoo(): void
 	{
 		echo $this->name ?? 'default';
 	}
 }