diff --git a/tests/PHPStan/Analyser/NodeScopeResolverTest.php b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
index 98c8d7740b..ecc5f625cd 100644
--- a/tests/PHPStan/Analyser/NodeScopeResolverTest.php
+++ b/tests/PHPStan/Analyser/NodeScopeResolverTest.php
@@ -443,6 +443,7 @@ public function dataFileAsserts(): iterable
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5259.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5293.php');
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-5129.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-4970.php');
 	}
 
 	/**
diff --git a/tests/PHPStan/Analyser/data/bug-4970.php b/tests/PHPStan/Analyser/data/bug-4970.php
new file mode 100644
index 0000000000..b4ac3cf0ea
--- /dev/null
+++ b/tests/PHPStan/Analyser/data/bug-4970.php
@@ -0,0 +1,29 @@
+<?php
+
+namespace Bug4970;
+
+use function PHPStan\Testing\assertType;
+
+class Test
+{
+	/**
+	 * @var string
+	 */
+	protected $importFile = '/a';
+
+	protected function beforeRun(): int
+	{
+		if (!\file_exists($this->importFile)) {
+			return 1;
+		}
+		assertType('true', \file_exists($this->importFile));
+		$this->importFile = '/b';
+		assertType('bool', \file_exists($this->importFile));
+
+		if (\file_exists($this->importFile)) {
+			echo 'test';
+		}
+
+		return \file_exists($this->importFile) ? 0 : 1;
+	}
+}