Add non regression test for 9386

Author: VincentLanglet

tests/PHPStan/Rules/Operators/InvalidComparisonOperationRuleTest.php

@@ -205,6 +205,11 @@ public function testBug13001(): void
 		]);
 	}
 
+	public function testBug9386(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-9386.php'], []);
+	}
+
 	public function testBug7280Comment(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-7280-comment.php'], []);

tests/PHPStan/Rules/Operators/data/bug-9386.php

@@ -0,0 +1,27 @@
+<?php declare(strict_types = 1);
+
+namespace Bug9386;
+
+trait BaseTrait {
+	protected false|int $_pos;
+
+	public function myMethod():bool {
+		$pos = $this->_pos;
+		if ($pos === false)
+			return false;
+		if (($this instanceof BaseClass) && $this->length !== null)
+			return $pos >= $this->offset + $this->length;
+		return false;
+	}
+}
+
+class BaseClass
+{
+	use BaseTrait;
+	protected ?int $length = null;
+	protected int $offset = 0;
+}
+class SecondClass
+{
+	use BaseTrait;
+}