From 3f7abf29a82ec0e81386d7d519133f8fe1f278dd Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <dktapps@pmmp.io>
Date: Wed, 20 Sep 2023 19:42:21 +0100
Subject: [PATCH] Added PHPStan rule to flag usages of legacy enum accessors
 provided by LegacyEnumShimTrait closes #6061

---
 phpstan.neon.dist                             |  1 +
 .../rules/DeprecatedLegacyEnumAccessRule.php  | 78 +++++++++++++++++++
 2 files changed, 79 insertions(+)
 create mode 100644 tests/phpstan/rules/DeprecatedLegacyEnumAccessRule.php

diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 581bf41ec..2fde67d6c 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -10,6 +10,7 @@ includes:
 	- vendor/phpstan/phpstan-strict-rules/rules.neon
 
 rules:
+	- pocketmine\phpstan\rules\DeprecatedLegacyEnumAccessRule
 	- pocketmine\phpstan\rules\DisallowEnumComparisonRule
 	- pocketmine\phpstan\rules\DisallowForeachByReferenceRule
 	- pocketmine\phpstan\rules\UnsafeForeachArrayOfStringRule
diff --git a/tests/phpstan/rules/DeprecatedLegacyEnumAccessRule.php b/tests/phpstan/rules/DeprecatedLegacyEnumAccessRule.php
new file mode 100644
index 000000000..2f17e6914
--- /dev/null
+++ b/tests/phpstan/rules/DeprecatedLegacyEnumAccessRule.php
@@ -0,0 +1,78 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+ */
+
+declare(strict_types=1);
+
+namespace pocketmine\phpstan\rules;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr\StaticCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+use PHPStan\Type\TypeWithClassName;
+use pocketmine\utils\LegacyEnumShimTrait;
+
+/**
+ * @phpstan-implements Rule<StaticCall>
+ */
+final class DeprecatedLegacyEnumAccessRule implements Rule{
+
+	public function getNodeType() : string{
+		return StaticCall::class;
+	}
+
+	public function processNode(Node $node, Scope $scope) : array{
+		/** @var StaticCall $node */
+		if(!$node->name instanceof Node\Identifier){
+			return [];
+		}
+		$caseName = $node->name->name;
+		$classType = $node->class instanceof Node\Name ?
+			$scope->resolveTypeByName($node->class) :
+			$scope->getType($node->class);
+
+		if(!$classType instanceof TypeWithClassName){
+			return [];
+		}
+
+		$reflection = $classType->getClassReflection();
+		if($reflection === null || !$reflection->hasTraitUse(LegacyEnumShimTrait::class) || !$reflection->implementsInterface(\UnitEnum::class)){
+			return [];
+		}
+
+		if(!$reflection->hasNativeMethod($caseName)){
+			return [
+				RuleErrorBuilder::message(sprintf(
+					'Use of legacy enum case accessor %s::%s().',
+					$reflection->getName(),
+					$caseName
+				))->tip(sprintf(
+					'Access the enum constant directly instead (remove the brackets), e.g. %s::%s',
+					$reflection->getName(),
+					$caseName
+				))->build()
+			];
+		}
+
+		return [];
+	}
+}