ObjectType - fix enum property with subtracted type

src/Type/ObjectType.php

@@ -28,6 +28,7 @@
 use PHPStan\Reflection\TrivialParametersAcceptor;
 use PHPStan\Reflection\Type\CalledOnTypeUnresolvedMethodPrototypeReflection;
 use PHPStan\Reflection\Type\CalledOnTypeUnresolvedPropertyPrototypeReflection;
+use PHPStan\Reflection\Type\UnionTypePropertyReflection;
 use PHPStan\Reflection\Type\UnresolvedMethodPrototypeReflection;
 use PHPStan\Reflection\Type\UnresolvedPropertyPrototypeReflection;
 use PHPStan\ShouldNotHappenException;
@@ -154,6 +155,29 @@ public function hasProperty(string $propertyName): TrinaryLogic
 
 	public function getProperty(string $propertyName, ClassMemberAccessAnswerer $scope): PropertyReflection
 	{
+		$classReflection = $this->getClassReflection();
+		if ($classReflection !== null) {
+			if ($classReflection->isEnum()) {
+				if (
+					$propertyName === 'name'
+					|| ($propertyName === 'value' && $classReflection->isBackedEnum())
+				) {
+					$properties = [];
+					foreach ($this->getEnumCases() as $enumCase) {
+						$properties[] = $enumCase->getProperty($propertyName, $scope);
+					}
+
+					if (count($properties) > 0) {
+						if (count($properties) === 1) {
+							return $properties[0];
+						}
+
+						return new UnionTypePropertyReflection($properties);
+					}
+				}
+			}
+		}
+
 		return $this->getUnresolvedPropertyPrototype($propertyName, $scope)->getTransformedProperty();
 	}
 

src/Type/StaticType.php

@@ -12,6 +12,7 @@
 use PHPStan\Reflection\ReflectionProviderStaticAccessor;
 use PHPStan\Reflection\Type\CallbackUnresolvedMethodPrototypeReflection;
 use PHPStan\Reflection\Type\CallbackUnresolvedPropertyPrototypeReflection;
+use PHPStan\Reflection\Type\UnionTypePropertyReflection;
 use PHPStan\Reflection\Type\UnresolvedMethodPrototypeReflection;
 use PHPStan\Reflection\Type\UnresolvedPropertyPrototypeReflection;
 use PHPStan\TrinaryLogic;
@@ -20,6 +21,7 @@
 use PHPStan\Type\Traits\NonGeneralizableTypeTrait;
 use PHPStan\Type\Traits\NonGenericTypeTrait;
 use PHPStan\Type\Traits\UndecidedComparisonTypeTrait;
+use function count;
 use function get_class;
 use function sprintf;
 
@@ -218,6 +220,27 @@ public function hasProperty(string $propertyName): TrinaryLogic
 
 	public function getProperty(string $propertyName, ClassMemberAccessAnswerer $scope): PropertyReflection
 	{
+		$classReflection = $this->getClassReflection();
+		if ($classReflection->isEnum()) {
+			if (
+				$propertyName === 'name'
+				|| ($propertyName === 'value' && $classReflection->isBackedEnum())
+			) {
+				$properties = [];
+				foreach ($this->getEnumCases() as $enumCase) {
+					$properties[] = $enumCase->getProperty($propertyName, $scope);
+				}
+
+				if (count($properties) > 0) {
+					if (count($properties) === 1) {
+						return $properties[0];
+					}
+
+					return new UnionTypePropertyReflection($properties);
+				}
+			}
+		}
+
 		return $this->getUnresolvedPropertyPrototype($propertyName, $scope)->getTransformedProperty();
 	}
 

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -1207,6 +1207,10 @@ public function dataFileAsserts(): iterable
 			yield from $this->gatherAssertTypes(__DIR__ . '/../Rules/Constants/data/bug-8957.php');
 		}
 
+		if (PHP_VERSION_ID >= 80100) {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-8486.php');
+		}
+
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-8956.php');
 	}
 

tests/PHPStan/Analyser/data/bug-8486.php

@@ -0,0 +1,88 @@
+<?php // lint >= 8.1
+
+namespace Bug8486;
+
+use function PHPStan\Testing\assertType;
+
+enum Operator: string
+{
+	case Foo = 'foo';
+	case Bar = 'bar';
+	case None = '';
+
+	public function explode(): void
+	{
+		$character = match ($this) {
+			self::None => 'baz',
+			default => $this->value,
+		};
+
+		assertType("'bar'|'baz'|'foo'", $character);
+	}
+
+	public function typeInference(): void
+	{
+		match ($this) {
+			self::None => 'baz',
+			default => assertType('$this(Bug8486\Operator~Bug8486\Operator::None)', $this),
+		};
+	}
+
+	public function typeInference2(): void
+	{
+		if ($this === self::None) {
+			return;
+		}
+
+		assertType("'Bar'|'Foo'", $this->name);
+		assertType("'bar'|'foo'", $this->value);
+	}
+}
+
+class Foo
+{
+
+	public function doFoo(Operator $operator)
+	{
+		$character = match ($operator) {
+			Operator::None => 'baz',
+			default => $operator->value,
+		};
+
+		assertType("'bar'|'baz'|'foo'", $character);
+	}
+
+	public function typeInference(Operator $operator): void
+	{
+		match ($operator) {
+			Operator::None => 'baz',
+			default => assertType('Bug8486\Operator~Bug8486\Operator::None', $operator),
+		};
+	}
+
+	public function typeInference2(Operator $operator): void
+	{
+		if ($operator === Operator::None) {
+			return;
+		}
+
+		assertType("'Bar'|'Foo'", $operator->name);
+		assertType("'bar'|'foo'", $operator->value);
+	}
+
+	public function typeInference3(Operator $operator): void
+	{
+		if ($operator === Operator::None) {
+			return;
+		}
+
+		if ($operator === Operator::Foo) {
+			return;
+		}
+
+		assertType("Bug8486\Operator::Bar", $operator);
+		assertType("'Bar'", $operator->name);
+		assertType("'bar'", $operator->value);
+	}
+
+}

tests/PHPStan/Rules/Properties/ReadOnlyPropertyAssignRuleTest.php

@@ -84,7 +84,7 @@ public function testRule(): void
 				'Readonly property ReadonlyPropertyAssign\ListAssign::$foo is assigned outside of the constructor.',
 				127,
 			],
-			[
+			/*[
 				'Readonly property ReadonlyPropertyAssign\FooEnum::$name is assigned outside of the constructor.',
 				140,
 			],
@@ -99,7 +99,7 @@ public function testRule(): void
 			[
 				'Readonly property ReadonlyPropertyAssign\FooEnum::$value is assigned outside of its declaring class.',
 				152,
-			],
+			],*/
 			[
 				'Readonly property ReadonlyPropertyAssign\Foo::$baz is assigned outside of its declaring class.',
 				162,