Add test

Author: VincentLanglet

tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php

@@ -2174,6 +2174,11 @@ public function testBug10020(): void
 		$this->analyse([__DIR__ . '/data/bug-10020.php'], []);
 	}
 
+	public function testBug8506(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-8506.php'], []);
+	}
+
 	public function testBug13065(): void
 	{
 		$errors = [];

tests/PHPStan/Rules/Functions/data/bug-8506.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Bug8506;
+
+function a(): ?int { return rand(0, 1) ? 1 : null; }
+function b(int $i, int ...$a): void {}
+
+$arguments = array_filter([
+	a(),
+	a(),
+	a(),
+]);
+
+if (!$arguments) {
+	return;
+}
+
+b(...$arguments);