more precise

Author: staabm

Diff for: src/Type/Constant/ConstantArrayType.php

@@ -35,6 +35,7 @@
 use PHPStan\Type\Generic\TemplateTypeMap;
 use PHPStan\Type\Generic\TemplateTypeVariance;
 use PHPStan\Type\IntegerRangeType;
+use PHPStan\Type\IntegerType;
 use PHPStan\Type\IntersectionType;
 use PHPStan\Type\IsSuperTypeOfResult;
 use PHPStan\Type\MixedType;
@@ -1256,8 +1257,8 @@ public function getKeysArrayFiltered(Type $filterValueType, bool $strict): Type
 
 		return TypeCombinator::intersect(
 			new ArrayType(
-				$keysArray->getIterableKeyType()->generalize(GeneralizePrecision::lessSpecific()),
-				$keysArray->getIterableValueType()->generalize(GeneralizePrecision::lessSpecific()),
+				new IntegerType(),
+				$keysArray->getIterableValueType(),
 			),
 			new AccessoryArrayListType(),
 		);

Diff for: tests/PHPStan/Analyser/nsrt/bug-11928.php

@@ -9,7 +9,7 @@ function doFoo()
 	$a = [2 => 1, 3 => 2, 4 => 1];
 
 	$keys = array_keys($a, 1); // returns [2, 4]
-	assertType('list<int>', $keys);
+	assertType('list<2|3|4>', $keys);
 
 	$keys = array_keys($a); // returns [2, 3, 4]
 	assertType('array{2, 3, 4}', $keys);
@@ -18,7 +18,7 @@ function doFoo()
 function doFooStrings() {
 	$a = [2 => 'hi', 3 => '123', 'xy' => 5];
 	$keys = array_keys($a, 1);
-	assertType('list<int|string>', $keys);
+	assertType("list<2|3|'xy'>", $keys);
 
 	$keys = array_keys($a);
 	assertType("array{2, 3, 'xy'}", $keys);