Handle static access, nullsafe access, and $this:: in trait $this check

Extend isExpressionDependentOnThis() to also recognize:
- NullsafePropertyFetch ($this?->foo)
- NullsafeMethodCall ($this?->method())
- StaticPropertyFetch (self::$foo, static::$foo, $this::$foo)
- StaticCall (self::method(), static::method(), $this::method())

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: phpstan-bot

src/Rules/Comparison/ImpossibleCheckTypeHelper.php

@@ -397,14 +397,23 @@ private static function isExpressionDependentOnThis(Expr $expr): bool
 			return true;
 		}
 
-		if ($expr instanceof Expr\PropertyFetch) {
+		if ($expr instanceof Expr\PropertyFetch || $expr instanceof Expr\NullsafePropertyFetch) {
 			return self::isExpressionDependentOnThis($expr->var);
 		}
 
-		if ($expr instanceof Expr\MethodCall) {
+		if ($expr instanceof Expr\MethodCall || $expr instanceof Expr\NullsafeMethodCall) {
 			return self::isExpressionDependentOnThis($expr->var);
 		}
 
+		if ($expr instanceof Expr\StaticPropertyFetch || $expr instanceof Expr\StaticCall) {
+			if ($expr->class instanceof Expr) {
+				return self::isExpressionDependentOnThis($expr->class);
+			}
+
+			$className = $expr->class->toString();
+			return in_array($className, ['self', 'static', 'parent'], true);
+		}
+
 		return false;
 	}
 

tests/PHPStan/Rules/Comparison/data/bug-13023.php

@@ -50,3 +50,63 @@ public function getRandom(): int
 		return $value;
 	}
 }
+
+class SomeClass5
+{
+	use MyTrait3;
+
+	public static string $bar = 'bar';
+}
+
+class SomeClass6
+{
+	use MyTrait3;
+
+	public static int $bar = 1;
+}
+
+trait MyTrait3
+{
+	public function getRandom(): int
+	{
+		$value = random_int(1, 100);
+		if (\is_int(self::$bar)) {
+			return $value * $value;
+		}
+		if (\is_int(static::$bar)) {
+			return $value * $value;
+		}
+		if (\is_int($this::$bar)) {
+			return $value * $value;
+		}
+
+		return $value;
+	}
+}
+
+class SomeClass7
+{
+	use MyTrait4;
+
+	public ?string $baz = 'baz';
+}
+
+class SomeClass8
+{
+	use MyTrait4;
+
+	public ?int $baz = 1;
+}
+
+trait MyTrait4
+{
+	public function getRandom(): int
+	{
+		$value = random_int(1, 100);
+		if (\is_int($this?->baz)) {
+			return $value * $value;
+		}
+
+		return $value;
+	}
+}