fix union/intersect involving enum case

Author: schlndh

phpstan-baseline.neon

@@ -1692,6 +1692,12 @@ parameters:
 			count: 5
 			path: src/Type/TypeCombinator.php
 
+		-
+			message: '#^Doing instanceof PHPStan\\Type\\Enum\\EnumCaseObjectType is error\-prone and deprecated\. Use Type\:\:getEnumCases\(\) instead\.$#'
+			identifier: phpstanApi.instanceofType
+			count: 2
+			path: src/Type/TypeCombinator.php
+
 		-
 			message: '#^Doing instanceof PHPStan\\Type\\FloatType is error\-prone and deprecated\. Use Type\:\:isFloat\(\) instead\.$#'
 			identifier: phpstanApi.instanceofType

src/Type/TypeCombinator.php

@@ -18,6 +18,7 @@
 use PHPStan\Type\Constant\ConstantFloatType;
 use PHPStan\Type\Constant\ConstantIntegerType;
 use PHPStan\Type\Constant\ConstantStringType;
+use PHPStan\Type\Enum\EnumCaseObjectType;
 use PHPStan\Type\Generic\GenericClassStringType;
 use PHPStan\Type\Generic\TemplateArrayType;
 use PHPStan\Type\Generic\TemplateBenevolentUnionType;
@@ -539,7 +540,7 @@ private static function unionWithSubtractedType(
 			return $type;
 		}
 
-		if ($type instanceof SubtractableType) {
+		if ($type instanceof SubtractableType && ! $type instanceof EnumCaseObjectType) {
 			$subtractedType = $type->getSubtractedType() === null
 				? $subtractedType
 				: self::union($type->getSubtractedType(), $subtractedType);
@@ -595,7 +596,7 @@ private static function intersectWithSubtractedType(
 			}
 
 			$subtractedType = self::union(...$subtractedTypes);
-		} elseif ($b instanceof SubtractableType) {
+		} elseif ($b instanceof SubtractableType && ! $b instanceof EnumCaseObjectType) {
 			$subtractedType = $b->getSubtractedType();
 			if ($subtractedType === null) {
 				return $a->getTypeWithoutSubtractedType();

tests/PHPStan/Analyser/nsrt/enum-vs-in-array.php

@@ -0,0 +1,43 @@
+<?php // lint >= 8.1
+
+declare(strict_types = 1);
+
+namespace EnumVsInArray;
+
+use function PHPStan\Testing\assertType;
+
+enum FooEnum
+{
+	case A;
+	case B;
+	case C;
+	case D;
+	case E;
+	case F;
+	case G;
+	case H;
+	case I;
+	case J;
+}
+
+function foo(FooEnum $e): int
+{
+	if (in_array($e, [FooEnum::A, FooEnum::B, FooEnum::C], true)) {
+		throw new \Exception('a');
+	}
+
+	assertType('EnumVsInArray\FooEnum~(EnumVsInArray\FooEnum::A|EnumVsInArray\FooEnum::B|EnumVsInArray\FooEnum::C)', $e);
+
+	if (rand(0, 10) === 1) {
+		if (!in_array($e, [FooEnum::D, FooEnum::E], true)) {
+			throw new \Exception('d');
+		}
+	}
+
+	assertType('EnumVsInArray\FooEnum~(EnumVsInArray\FooEnum::A|EnumVsInArray\FooEnum::B|EnumVsInArray\FooEnum::C)', $e);
+
+	return match ($e) {
+		FooEnum::D, FooEnum::E, FooEnum::F, FooEnum::G, FooEnum::H, FooEnum::I => 2,
+		FooEnum::J => 3,
+	};
+}

tests/PHPStan/Type/TypeCombinatorTest.php

@@ -2262,6 +2262,36 @@ public function dataUnion(): iterable
 			'PHPStan\Fixture\ManyCasesTestEnum~PHPStan\Fixture\ManyCasesTestEnum::A',
 		];
 
+		yield [
+			[
+				new ObjectType('PHPStan\Fixture\ManyCasesTestEnum', new UnionType([
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A'),
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'B'),
+				])),
+				new UnionType([
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'C'),
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'D'),
+				]),
+			],
+			ObjectType::class,
+			'PHPStan\Fixture\ManyCasesTestEnum~(PHPStan\Fixture\ManyCasesTestEnum::A|PHPStan\Fixture\ManyCasesTestEnum::B)',
+		];
+
+		yield [
+			[
+				new ObjectType('PHPStan\Fixture\ManyCasesTestEnum', new UnionType([
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A'),
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'B'),
+				])),
+				new UnionType([
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A'),
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'D'),
+				]),
+			],
+			ObjectType::class,
+			'PHPStan\Fixture\ManyCasesTestEnum~PHPStan\Fixture\ManyCasesTestEnum::B',
+		];
+
 		yield [
 			[
 				new ThisType(
@@ -4224,6 +4254,27 @@ public function dataIntersect(): iterable
 			'$this(stdClass)&stdClass::foo',
 		];
 
+		yield [
+			[
+				new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A'),
+				new MixedType(false, new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A')),
+			],
+			NeverType::class,
+			'*NEVER*=implicit',
+		];
+
+		yield [
+			[
+				new UnionType([
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A'),
+					new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'B'),
+				]),
+				new MixedType(false, new EnumCaseObjectType('PHPStan\Fixture\ManyCasesTestEnum', 'A')),
+			],
+			EnumCaseObjectType::class,
+			'PHPStan\Fixture\ManyCasesTestEnum::B',
+		];
+
 		yield [
 			[
 				TypeCombinator::intersect(new StringType(), new AccessoryNonEmptyStringType()),