Narrow TemplateMixedType in TypeCombinator::intersect() for scalar types

Revert IntersectionType changes and instead narrow TemplateMixedType
to a concrete template type (e.g. TemplateIntegerType) when intersected
with a scalar type in TypeCombinator::intersect().

For `int & T` where T is TemplateMixedType, the result is now
`T of int` (TemplateIntegerType) instead of an IntersectionType.
Since TemplateIntegerType delegates hasMethod() to IntegerType (which
returns No for __toString), the false positive purity error is avoided.

The narrowing is restricted to scalar types only. Narrowing object
or array types would cause information loss during template resolution
(e.g. `T&MockObject` becoming just the resolved type without MockObject).

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

Author: phpstan-bot

src/Type/IntersectionType.php

@@ -552,7 +552,7 @@ public function canAccessProperties(): TrinaryLogic
 
 	public function hasProperty(string $propertyName): TrinaryLogic
 	{
-		return $this->intersectResultsWithNonObjectGuard(static fn (Type $type): TrinaryLogic => $type->hasProperty($propertyName));
+		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasProperty($propertyName));
 	}
 
 	public function getProperty(string $propertyName, ClassMemberAccessAnswerer $scope): ExtendedPropertyReflection
@@ -585,7 +585,7 @@ public function getUnresolvedPropertyPrototype(string $propertyName, ClassMember
 
 	public function hasInstanceProperty(string $propertyName): TrinaryLogic
 	{
-		return $this->intersectResultsWithNonObjectGuard(static fn (Type $type): TrinaryLogic => $type->hasInstanceProperty($propertyName));
+		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasInstanceProperty($propertyName));
 	}
 
 	public function getInstanceProperty(string $propertyName, ClassMemberAccessAnswerer $scope): ExtendedPropertyReflection
@@ -618,7 +618,7 @@ public function getUnresolvedInstancePropertyPrototype(string $propertyName, Cla
 
 	public function hasStaticProperty(string $propertyName): TrinaryLogic
 	{
-		return $this->intersectResultsWithNonObjectGuard(static fn (Type $type): TrinaryLogic => $type->hasStaticProperty($propertyName));
+		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasStaticProperty($propertyName));
 	}
 
 	public function getStaticProperty(string $propertyName, ClassMemberAccessAnswerer $scope): ExtendedPropertyReflection
@@ -656,7 +656,7 @@ public function canCallMethods(): TrinaryLogic
 
 	public function hasMethod(string $methodName): TrinaryLogic
 	{
-		return $this->intersectResultsWithNonObjectGuard(static fn (Type $type): TrinaryLogic => $type->hasMethod($methodName));
+		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasMethod($methodName));
 	}
 
 	public function getMethod(string $methodName, ClassMemberAccessAnswerer $scope): ExtendedMethodReflection
@@ -694,7 +694,7 @@ public function canAccessConstants(): TrinaryLogic
 
 	public function hasConstant(string $constantName): TrinaryLogic
 	{
-		return $this->intersectResultsWithNonObjectGuard(static fn (Type $type): TrinaryLogic => $type->hasConstant($constantName));
+		return $this->intersectResults(static fn (Type $type): TrinaryLogic => $type->hasConstant($constantName));
 	}
 
 	public function getConstant(string $constantName): ClassConstantReflection
@@ -1483,23 +1483,6 @@ private function intersectResults(
 		return TrinaryLogic::lazyMaxMin($types, $getResult);
 	}
 
-	/**
-	 * @param callable(Type $type): TrinaryLogic $getResult
-	 */
-	private function intersectResultsWithNonObjectGuard(callable $getResult): TrinaryLogic
-	{
-		$results = [];
-		foreach ($this->types as $type) {
-			$result = $getResult($type);
-			if ($type->isObject()->no() && $result->no()) {
-				return TrinaryLogic::createNo();
-			}
-			$results[] = $result;
-		}
-
-		return TrinaryLogic::maxMin(...$results);
-	}
-
 	/**
 	 * @param callable(Type $type): Type $getType
 	 */

src/Type/TypeCombinator.php

@@ -1399,6 +1399,50 @@ public static function intersect(Type ...$types): Type
 					continue;
 				}
 
+				if (
+					$types[$j] instanceof TemplateMixedType
+					&& !$types[$i] instanceof TemplateType
+					&& $types[$i]->isScalar()->yes()
+					&& $types[$j]->getBound()->isSuperTypeOf($types[$i])->yes()
+				) {
+					$narrowed = TemplateTypeFactory::create(
+						$types[$j]->getScope(),
+						$types[$j]->getName(),
+						$types[$i],
+						$types[$j]->getVariance(),
+						$types[$j]->getStrategy(),
+						$types[$j]->getDefault(),
+					);
+					if (!$narrowed instanceof TemplateMixedType) {
+						$types[$j] = $narrowed;
+						array_splice($types, $i--, 1);
+						$typesCount--;
+						continue 2;
+					}
+				}
+
+				if (
+					$types[$i] instanceof TemplateMixedType
+					&& !$types[$j] instanceof TemplateType
+					&& $types[$j]->isScalar()->yes()
+					&& $types[$i]->getBound()->isSuperTypeOf($types[$j])->yes()
+				) {
+					$narrowed = TemplateTypeFactory::create(
+						$types[$i]->getScope(),
+						$types[$i]->getName(),
+						$types[$j],
+						$types[$i]->getVariance(),
+						$types[$i]->getStrategy(),
+						$types[$i]->getDefault(),
+					);
+					if (!$narrowed instanceof TemplateMixedType) {
+						$types[$i] = $narrowed;
+						array_splice($types, $j--, 1);
+						$typesCount--;
+						continue;
+					}
+				}
+
 				if ($types[$i] instanceof IterableType) {
 					$isSuperTypeB = $types[$i]->isSuperTypeOfMixed($types[$j]);
 				} else {

tests/PHPStan/Analyser/nsrt/bug-4117.php

@@ -34,7 +34,7 @@ public function broken(int $key)
 		if ($item) {
 			assertType("T of mixed~(0|0.0|''|'0'|array{}|false|null) (class Bug4117Types\GenericList, argument)", $item);
 		} else {
-			assertType("(T of mixed~null (class Bug4117Types\GenericList, argument)&false)|(0.0&T of mixed~null (class Bug4117Types\GenericList, argument))|(0&T of mixed~null (class Bug4117Types\GenericList, argument))|(list{}&T of mixed~null (class Bug4117Types\GenericList, argument))|(''&T of mixed~null (class Bug4117Types\GenericList, argument))|('0'&T of mixed~null (class Bug4117Types\GenericList, argument))|null", $item);
+			assertType("T of 0 (class Bug4117Types\GenericList, argument)|T of '' (class Bug4117Types\GenericList, argument)|T of '0' (class Bug4117Types\GenericList, argument)|(T of mixed~null (class Bug4117Types\GenericList, argument)&false)|(0.0&T of mixed~null (class Bug4117Types\GenericList, argument))|(list{}&T of mixed~null (class Bug4117Types\GenericList, argument))|null", $item);
 		}
 
 		assertType('T of mixed~null (class Bug4117Types\GenericList, argument)|null', $item);

tests/PHPStan/Analyser/nsrt/bug-4498.php

@@ -38,7 +38,7 @@ public function fcn(iterable $iterable): iterable
 	public function bar(iterable $iterable): iterable
 	{
 		if (is_array($iterable)) {
-			assertType('array<((int&TKey (method Bug4498\Foo::bar(), argument))|(string&TKey (method Bug4498\Foo::bar(), argument))), TValue (method Bug4498\Foo::bar(), argument)>', $iterable);
+			assertType('array<(TKey of int (method Bug4498\Foo::bar(), argument)|TKey of string (method Bug4498\Foo::bar(), argument)), TValue (method Bug4498\Foo::bar(), argument)>', $iterable);
 			return $iterable;
 		}
 

tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php

@@ -725,11 +725,11 @@ public function testArrayUdiffCallback(): void
 				14,
 			],
 			[
-				'Parameter #1 $arr1 of function array_udiff expects array<(int&TK)|(string&TK), string>, null given.',
+				'Parameter #1 $arr1 of function array_udiff expects array<(TK of int)|TK of string, string>, null given.',
 				20,
 			],
 			[
-				'Parameter #2 $arr2 of function array_udiff expects array<(int&TK)|(string&TK), string>, null given.',
+				'Parameter #2 $arr2 of function array_udiff expects array<(TK of int)|TK of string, string>, null given.',
 				21,
 			],
 			[