Make ArrayFindFunctionReturnTypeExtension a wrapper for array_filter()

Author: zonuexe

src/Type/Php/ArrayFindFunctionReturnTypeExtension.php

@@ -3,12 +3,14 @@
 namespace PHPStan\Type\Php;
 
 use PhpParser\Node\Expr\FuncCall;
+use PhpParser\Node\Name;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\NullType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
+use function array_map;
 use function count;
 
 final class ArrayFindFunctionReturnTypeExtension implements DynamicFunctionReturnTypeExtension
@@ -30,7 +32,9 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 			return null;
 		}
 
-		return TypeCombinator::union($arrayType->getIterableValueType(), new NullType());
+		$resultTypes = $scope->getType(new FuncCall(new Name('\array_filter'), $functionCall->getArgs()))->getArrays();
+
+		return TypeCombinator::union(new NullType(), ...array_map(fn ($type) => $type->getIterableValueType(), $resultTypes));
 	}
 
 }

tests/PHPStan/Analyser/nsrt/array-find.php

@@ -28,7 +28,7 @@ function array_find(array $array, callable $callback)
 	function testMixed(array $array, callable $callback): void
 	{
 		assertType('mixed', array_find($array, $callback));
-		assertType('mixed', array_find($array, 'is_int'));
+		assertType('int|null', array_find($array, 'is_int'));
 	}
 
 	/**
@@ -37,7 +37,7 @@ function testMixed(array $array, callable $callback): void
 	function testConstant(array $array, callable $callback): void
 	{
 		assertType("1|'foo'|DateTime|null", array_find($array, $callback));
-		assertType("1|'foo'|DateTime|null", array_find($array, 'is_int'));
+		assertType("1|null", array_find($array, 'is_int'));
 	}
 
 }