Some sort functions do not preserve a list

Author: ondrejmirtes

src/Analyser/NodeScopeResolver.php

@@ -2192,8 +2192,21 @@ static function (): void {
 				$arrayArg = $expr->getArgs()[0]->value;
 				$scope = $scope->assignExpression(
 					$arrayArg,
-					$this->getArraySortFunctionType($scope->getType($arrayArg)),
-					$this->getArraySortFunctionType($scope->getNativeType($arrayArg)),
+					$this->getArraySortPreserveListFunctionType($scope->getType($arrayArg)),
+					$this->getArraySortPreserveListFunctionType($scope->getNativeType($arrayArg)),
+				);
+			}
+
+			if (
+				$functionReflection !== null
+				&& in_array($functionReflection->getName(), ['natcasesort', 'natsort', 'arsort', 'asort', 'ksort', 'krsort', 'uasort', 'uksort'], true)
+				&& count($expr->getArgs()) >= 1
+			) {
+				$arrayArg = $expr->getArgs()[0]->value;
+				$scope = $scope->assignExpression(
+					$arrayArg,
+					$this->getArraySortDoNotPreserveListFunctionType($scope->getType($arrayArg)),
+					$this->getArraySortDoNotPreserveListFunctionType($scope->getNativeType($arrayArg)),
 				);
 			}
 
@@ -3157,7 +3170,7 @@ static function (?Type $offsetType, Type $valueType, bool $optional) use (&$arra
 		return $arrayType;
 	}
 
-	private function getArraySortFunctionType(Type $type): Type
+	private function getArraySortPreserveListFunctionType(Type $type): Type
 	{
 		$isIterableAtLeastOnce = $type->isIterableAtLeastOnce();
 		if ($isIterableAtLeastOnce->no()) {
@@ -3182,6 +3195,27 @@ private function getArraySortFunctionType(Type $type): Type
 		});
 	}
 
+	private function getArraySortDoNotPreserveListFunctionType(Type $type): Type
+	{
+		$isIterableAtLeastOnce = $type->isIterableAtLeastOnce();
+		if ($isIterableAtLeastOnce->no()) {
+			return $type;
+		}
+
+		return TypeTraverser::map($type, static function (Type $type, callable $traverse) use ($isIterableAtLeastOnce): Type {
+			if ($type instanceof UnionType) {
+				return $traverse($type);
+			}
+
+			$newArrayType = new ArrayType($type->getIterableKeyType(), $type->getIterableValueType());
+			if ($isIterableAtLeastOnce->yes()) {
+				$newArrayType = TypeCombinator::intersect($newArrayType, new NonEmptyArrayType());
+			}
+
+			return $newArrayType;
+		});
+	}
+
 	private function getFunctionThrowPoint(
 		FunctionReflection $functionReflection,
 		?ParametersAcceptor $parametersAcceptor,

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -654,6 +654,7 @@ public function dataFileAsserts(): iterable
 		}
 
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/never.php');
+		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-10627.php');
 
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/native-intersection.php');
 

tests/PHPStan/Analyser/data/bug-10627.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace Bug10627;
+
+use function PHPStan\Testing\assertType;
+
+class HelloWorld
+{
+	public function sayHello(): void
+	{
+		$list = ['A', 'C', 'B'];
+		natcasesort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello2(): void
+	{
+		$list = ['A', 'C', 'B'];
+		natsort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello3(): void
+	{
+		$list = ['A', 'C', 'B'];
+		arsort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello4(): void
+	{
+		$list = ['A', 'C', 'B'];
+		asort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello5(): void
+	{
+		$list = ['A', 'C', 'B'];
+		ksort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello6(): void
+	{
+		$list = ['A', 'C', 'B'];
+		uasort($list, function () {
+
+		});
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello7(): void
+	{
+		$list = ['A', 'C', 'B'];
+		uksort($list, function () {
+
+		});
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	public function sayHello8(): void
+	{
+		$list = ['A', 'C', 'B'];
+		krsort($list);
+		assertType("non-empty-array<0|1|2, 'A'|'B'|'C'>", $list);
+	}
+
+	/**
+	 * @param list<string> $list
+	 * @return void
+	 */
+	public function sayHello9(array $list): void
+	{
+		krsort($list);
+		assertType("array<int<0, max>, string>", $list);
+	}
+}

tests/PHPStan/Analyser/data/param-out.php

@@ -221,7 +221,7 @@ function foo15() {
 		$manifest,
 		"fooCompare"
 	);
-	assertType('array{1, 2, 3}', $manifest);
+	assertType('non-empty-array<0|1|2, 1|2|3>', $manifest);
 }
 
 function fooSpaceship (string $a, string $b): int {
@@ -234,7 +234,7 @@ function foo16() {
 		$array,
 		"fooSpaceship"
 	);
-	assertType('array{1, 2}', $array);
+	assertType('non-empty-array<0|1, 1|2>', $array);
 }
 
 function fooShuffle() {