Properly support constant arrays in array_reverse

phpstan · May 24, 2022 · 00ec4af · 00ec4af
1 parent 9b7ef13
commit 00ec4af
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Showing 2 changed files with 27 additions and 8 deletions.
diff --git a/src/Type/Php/ArrayReverseFunctionReturnTypeExtension.php b/src/Type/Php/ArrayReverseFunctionReturnTypeExtension.php
@@ -5,12 +5,14 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
-use PHPStan\Reflection\ParametersAcceptorSelector;
 use PHPStan\Type\Constant\ConstantArrayType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
+use PHPStan\Type\IntersectionType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\Type;
+use PHPStan\Type\TypeTraverser;
+use PHPStan\Type\UnionType;
 
 class ArrayReverseFunctionReturnTypeExtension implements DynamicFunctionReturnTypeExtension
 {
@@ -20,21 +22,29 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 		return $functionReflection->getName() === 'array_reverse';
 	}
 
-	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
+	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): ?Type
 	{
 		if (!isset($functionCall->getArgs()[0])) {
-			return ParametersAcceptorSelector::selectSingle($functionReflection->getVariants())->getReturnType();
+			return null;
 		}
 
 		$type = $scope->getType($functionCall->getArgs()[0]->value);
 		$preserveKeysType = isset($functionCall->getArgs()[1]) ? $scope->getType($functionCall->getArgs()[1]->value) : new NeverType();
 		$preserveKeys = $preserveKeysType instanceof ConstantBooleanType ? $preserveKeysType->getValue() : false;
 
-		if ($type instanceof ConstantArrayType) {
-			return $type->reverse($preserveKeys);
+		if (!$type->isIterable()->yes()) {
+			return null;
 		}
 
-		return $type;
+		return TypeTraverser::map($type, static function (Type $type, callable $traverse) use ($preserveKeys): Type {
+			if ($type instanceof UnionType || $type instanceof IntersectionType) {
+				return $traverse($type);
+			}
+			if ($type instanceof ConstantArrayType) {
+				return $type->reverse($preserveKeys);
+			}
+			return $type;
+		});
 	}
 
 }
diff --git a/tests/PHPStan/Analyser/data/array-reverse.php b/tests/PHPStan/Analyser/data/array-reverse.php
@@ -19,9 +19,15 @@ public function normalArrays(array $a, array $b): void
 		assertType('array<string, int>', array_reverse($b, true));
 	}
 
-	/** @param array{a: 'foo', b: 'bar', c?: 'baz'} $a */
-	public function constantArrays(array $a): void
+	/**
+	 * @param array{a: 'foo', b: 'bar', c?: 'baz'} $a
+	 * @param array{17: 'foo', 19: 'bar'}|array{foo: 17, bar: 19} $b
+	 */
+	public function constantArrays(array $a, array $b): void
 	{
+		assertType('array{}', array_reverse([]));
+		assertType('array{}', array_reverse([], true));
+
 		assertType('array{1337, null, 42}', array_reverse([42, null, 1337]));
 		assertType('array{2: 1337, 1: null, 0: 42}', array_reverse([42, null, 1337], true));
 
@@ -36,5 +42,8 @@ public function constantArrays(array $a): void
 
 		assertType('array{c?: \'baz\', b: \'bar\', a: \'foo\'}', array_reverse($a));
 		assertType('array{c?: \'baz\', b: \'bar\', a: \'foo\'}', array_reverse($a, true));
+
+		assertType('array{\'bar\', \'foo\'}|array{bar: 19, foo: 17}', array_reverse($b));
+		assertType('array{19: \'bar\', 17: \'foo\'}|array{bar: 19, foo: 17}', array_reverse($b, true));
 	}
 }