Error Identifier: new.nonObject

← Back to new.*

Every error reported by PHPStan has an error identifier. Here’s a list of all error identifiers. In PHPStan Pro you can see the error identifier next to each error and filter errors by their identifiers.

Code example #

<?php declare(strict_types = 1);

function doFoo(int $int): void
{
	new $int;
}

Why is it reported? #

The dynamic instantiation syntax new $expr requires $expr to be either a string holding a class name or an object whose class should be instantiated. When $expr is any other type — such as int, float, bool, array, or a union that includes those types — PHP throws a fatal Error at runtime:

Uncaught Error: Class name must be a valid object or a string

A nullable string (string|null) is also reported, because passing null triggers the same fatal error.

How to fix it #

Make sure the expression used after new resolves to a class name or an object. Narrow the type so the non-object cases are excluded:

-function doFoo(int $int): void
+function doFoo(string $class): void
 {
-	new $int;
+	new $class;
 }

When the value can legitimately hold several types, narrow the type before instantiating:

 /** @param int|string $intOrString */
 function doFoo($intOrString): void
 {
+	if (!is_string($intOrString)) {
+		return;
+	}
 	new $intOrString;
 }

For a parameter that is meant to receive a class name, use the class-string type so PHPStan and other developers know only class names are accepted:

-/** @param string $class */
+/** @param class-string $class */
 function doFoo(string $class): void
 {
 	new $class;
 }

How to ignore this error #

You can use the identifier new.nonObject to ignore this error using a comment:

// @phpstan-ignore new.nonObject
codeThatProducesTheError();

You can also use only the identifier key to ignore all errors of the same type in your configuration file in the ignoreErrors parameter:

parameters:
	ignoreErrors:
		-
			identifier: new.nonObject

Rules that report this error #

• PHPStan\Rules\Classes\InstantiationRule [1]