Add regression tests for related dependent type narrowing issues

Add NSRT regression tests for:
- phpstan/phpstan#10843: match(true) with instanceof type narrowing
- phpstan/phpstan#14211: repeated if($m) check with isset-based bool
- phpstan/phpstan#11328: backed enum in_array conditional narrowing
- phpstan/phpstan#10085: list type incorrectly inferred as non-empty

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

Author: phpstan-bot

tests/PHPStan/Analyser/nsrt/bug-10085.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Bug10085;
+
+use function PHPStan\Testing\assertType;
+
+class HelloWorld
+{
+	/**
+	 * @param array<int, string> $foo
+	 * @param list<string> $bar
+	 */
+	public function sayHello(array $foo, array $bar): void
+	{
+		$a = $foo;
+		if ($a === []) {
+			$a = $bar;
+		}
+
+		if ($a === []) {
+			return;
+		}
+
+		assertType('array<int, string>', $foo);
+	}
+}

tests/PHPStan/Analyser/nsrt/bug-10843.php

@@ -0,0 +1,25 @@
+<?php // lint >= 8.0
+
+declare(strict_types = 1);
+
+namespace Bug10843;
+
+use function PHPStan\Testing\assertType;
+
+class HelloWorld
+{
+	public function sayHello(HelloWorld|null $date): int
+	{
+		$a = match (true) {
+			$date instanceof HelloWorld => 1,
+			default => false
+		};
+
+		if ($date instanceof HelloWorld) {
+			assertType('1|false', $a);
+			return $a;
+		}
+
+		throw new \Exception('Error');
+	}
+}

tests/PHPStan/Analyser/nsrt/bug-11328.php

@@ -0,0 +1,33 @@
+<?php // lint >= 8.1
+
+declare(strict_types = 1);
+
+namespace Bug11328;
+
+use function PHPStan\Testing\assertType;
+
+enum Status: string {
+	case Live = 's1';
+	case Expired = 's2';
+}
+
+/** @param Status[] $statuses */
+function check(array $statuses): void {
+	$fromDeadline = null;
+	$toDeadline = null;
+
+	if (in_array(Status::Live, $statuses, true)) {
+		$fromDeadline = (new \DateTimeImmutable())->setTime(23, 59, 59);
+	}
+
+	assertType('DateTimeImmutable|null', $fromDeadline);
+
+	if (in_array(Status::Expired, $statuses, true)) {
+		assertType('DateTimeImmutable|null', $fromDeadline);
+		if ($fromDeadline === null) {
+			$toDeadline = (new \DateTimeImmutable())->setTime(0, 0, 0);
+		} else {
+			$fromDeadline = null;
+		}
+	}
+}

tests/PHPStan/Analyser/nsrt/bug-14211.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Bug14211;
+
+use function PHPStan\Testing\assertType;
+
+/** @param array<mixed> $data */
+function doSomething(array $data): bool
+{
+	if (!isset($data['x'])) {
+		return false;
+	}
+
+	$m = isset($data['y']);
+
+	if ($m) {
+		assertType('true', $m);
+	}
+	assertType('bool', $m);
+
+	if ($m) {
+		assertType('true', $m);
+	}
+
+	return true;
+}