From 62148f3217ce27e4739020301da237e8992864a6 Mon Sep 17 00:00:00 2001
From: Emil Masiakowski <emil.masiakowski@amsterdamstandard.com>
Date: Wed, 21 Feb 2024 20:25:58 +0100
Subject: [PATCH] Fix false issue when passing enum case to generic class

Fixes #10484
---
 src/Type/Generic/TemplateTypeVariance.php     |  7 +++++++
 .../Rules/Methods/CallMethodsRuleTest.php     | 12 +++++++++++
 .../PHPStan/Rules/Methods/data/bug-10484.php  | 21 +++++++++++++++++++
 3 files changed, 40 insertions(+)
 create mode 100644 tests/PHPStan/Rules/Methods/data/bug-10484.php

diff --git a/src/Type/Generic/TemplateTypeVariance.php b/src/Type/Generic/TemplateTypeVariance.php
index a3ab7a04bd..e6097064bb 100644
--- a/src/Type/Generic/TemplateTypeVariance.php
+++ b/src/Type/Generic/TemplateTypeVariance.php
@@ -7,6 +7,7 @@
 use PHPStan\TrinaryLogic;
 use PHPStan\Type\AcceptsResult;
 use PHPStan\Type\BenevolentUnionType;
+use PHPStan\Type\GeneralizePrecision;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
@@ -157,6 +158,12 @@ public function isValidVarianceWithReason(?TemplateType $templateType, Type $a,
 			return AcceptsResult::createYes();
 		}
 
+		if ($b->isEnum()->yes()) {
+			if ($b->generalize(GeneralizePrecision::lessSpecific())->equals($a)) {
+				return AcceptsResult::createYes();
+			}
+		}
+
 		if ($this->invariant()) {
 			$result = $a->equals($b);
 			$reasons = [];
diff --git a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
index ed69d28980..cb4e74ee33 100644
--- a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
+++ b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
@@ -2529,6 +2529,18 @@ public function testBug5869(): void
 		$this->analyse([__DIR__ . '/data/bug-5869.php'], []);
 	}
 
+	public function testBug10484(): void
+	{
+		if (PHP_VERSION_ID < 80100) {
+			$this->markTestSkipped('Test requires PHP 8.1.');
+		}
+
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->analyse([__DIR__ . '/data/bug-10484.php'], []);
+	}
+
 	public function testGenericsEmptyArray(): void
 	{
 		$this->checkThisOnly = false;
diff --git a/tests/PHPStan/Rules/Methods/data/bug-10484.php b/tests/PHPStan/Rules/Methods/data/bug-10484.php
new file mode 100644
index 0000000000..2e9c915f51
--- /dev/null
+++ b/tests/PHPStan/Rules/Methods/data/bug-10484.php
@@ -0,0 +1,21 @@
+<?php
+
+namespace Bug10484;
+
+enum Foo {
+	case Bar;
+}
+
+class Test {
+	/**
+	 * @param \Ds\Set<Foo> $foos
+	 */
+	public function bar(\Ds\Set $foos): void
+	{
+	}
+
+	public function test(): void
+	{
+		$this->bar(new \Ds\Set([Foo::Bar]));
+	}
+}