Fix return type of round/ceil/floor in non strict type environment

In non declare strict types the round functions are able to handle numeric strings, null and bools.

See also: https://3v4l.org/5io0n

And issue phpstan/phpstan#11319

Author: BackEndTea

src/Type/Php/RoundFunctionReturnTypeExtension.php

@@ -6,13 +6,17 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\Php\PhpVersion;
 use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\Accessory\AccessoryNumericStringType;
+use PHPStan\Type\BooleanType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\FloatType;
 use PHPStan\Type\IntegerType;
+use PHPStan\Type\IntersectionType;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\NullType;
+use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\TypeCombinator;
 use function count;
@@ -67,6 +71,19 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 				new IntegerType(),
 				new FloatType(),
 			);
+
+			if (!$scope->isDeclareStrictTypes()) {
+				$allowed = TypeCombinator::union(
+					$allowed,
+					new IntersectionType([
+						new StringType(),
+						new AccessoryNumericStringType(),
+					]),
+					new NullType(),
+					new BooleanType(),
+				);
+			}
+
 			if ($allowed->isSuperTypeOf($firstArgType)->no()) {
 				// PHP 8 fatals if the parameter is not an integer or float.
 				return new NeverType(true);

tests/PHPStan/Analyser/nsrt/round-php8-strict-types.php

@@ -0,0 +1,63 @@
+<?php // lint >= 8.0
+
+declare(strict_types=1);
+
+namespace RoundFamilyTestPHP8StrictTypes;
+
+use function PHPStan\Testing\assertType;
+
+$maybeNull = null;
+if (rand(0, 1)) {
+	$maybeNull = 1.0;
+}
+
+// Round
+assertType('float', round(123));
+assertType('float', round(123.456));
+assertType('float', round($_GET['foo'] / 60));
+assertType('*NEVER*', round('123'));
+assertType('*NEVER*', round('123.456'));
+assertType('*NEVER*', round(null));
+assertType('float', round($maybeNull));
+assertType('*NEVER*', round(true));
+assertType('*NEVER*', round(false));
+assertType('*NEVER*', round(new \stdClass));
+assertType('*NEVER*', round(''));
+assertType('*NEVER*', round(array()));
+assertType('*NEVER*', round(array(123)));
+assertType('*NEVER*', round());
+assertType('float', round($_GET['foo']));
+
+// Ceil
+assertType('float', ceil(123));
+assertType('float', ceil(123.456));
+assertType('float', ceil($_GET['foo'] / 60));
+assertType('*NEVER*', ceil('123'));
+assertType('*NEVER*', ceil('123.456'));
+assertType('*NEVER*', ceil(null));
+assertType('float', ceil($maybeNull));
+assertType('*NEVER*', ceil(true));
+assertType('*NEVER*', ceil(false));
+assertType('*NEVER*', ceil(new \stdClass));
+assertType('*NEVER*', ceil(''));
+assertType('*NEVER*', ceil(array()));
+assertType('*NEVER*', ceil(array(123)));
+assertType('*NEVER*', ceil());
+assertType('float', ceil($_GET['foo']));
+
+// Floor
+assertType('float', floor(123));
+assertType('float', floor(123.456));
+assertType('float', floor($_GET['foo'] / 60));
+assertType('*NEVER*', floor('123'));
+assertType('*NEVER*', floor('123.456'));
+assertType('*NEVER*', floor(null));
+assertType('float', floor($maybeNull));
+assertType('*NEVER*', floor(true));
+assertType('*NEVER*', floor(false));
+assertType('*NEVER*', floor(new \stdClass));
+assertType('*NEVER*', floor(''));
+assertType('*NEVER*', floor(array()));
+assertType('*NEVER*', floor(array(123)));
+assertType('*NEVER*', floor());
+assertType('float', floor($_GET['foo']));

tests/PHPStan/Analyser/nsrt/round-php8.php

@@ -13,12 +13,12 @@
 assertType('float', round(123));
 assertType('float', round(123.456));
 assertType('float', round($_GET['foo'] / 60));
-assertType('*NEVER*', round('123'));
-assertType('*NEVER*', round('123.456'));
-assertType('*NEVER*', round(null));
+assertType('float', round('123'));
+assertType('float', round('123.456'));
+assertType('float', round(null));
 assertType('float', round($maybeNull));
-assertType('*NEVER*', round(true));
-assertType('*NEVER*', round(false));
+assertType('float', round(true));
+assertType('float', round(false));
 assertType('*NEVER*', round(new \stdClass));
 assertType('*NEVER*', round(''));
 assertType('*NEVER*', round(array()));
@@ -30,12 +30,12 @@
 assertType('float', ceil(123));
 assertType('float', ceil(123.456));
 assertType('float', ceil($_GET['foo'] / 60));
-assertType('*NEVER*', ceil('123'));
-assertType('*NEVER*', ceil('123.456'));
-assertType('*NEVER*', ceil(null));
+assertType('float', ceil('123'));
+assertType('float', ceil('123.456'));
+assertType('float', ceil(null));
 assertType('float', ceil($maybeNull));
-assertType('*NEVER*', ceil(true));
-assertType('*NEVER*', ceil(false));
+assertType('float', ceil(true));
+assertType('float', ceil(false));
 assertType('*NEVER*', ceil(new \stdClass));
 assertType('*NEVER*', ceil(''));
 assertType('*NEVER*', ceil(array()));
@@ -47,12 +47,12 @@
 assertType('float', floor(123));
 assertType('float', floor(123.456));
 assertType('float', floor($_GET['foo'] / 60));
-assertType('*NEVER*', floor('123'));
-assertType('*NEVER*', floor('123.456'));
-assertType('*NEVER*', floor(null));
+assertType('float', floor('123'));
+assertType('float', floor('123.456'));
+assertType('float', floor(null));
 assertType('float', floor($maybeNull));
-assertType('*NEVER*', floor(true));
-assertType('*NEVER*', floor(false));
+assertType('float', floor(true));
+assertType('float', floor(false));
 assertType('*NEVER*', floor(new \stdClass));
 assertType('*NEVER*', floor(''));
 assertType('*NEVER*', floor(array()));