Correctly account for an unknown parameter type.

phpstan · Feb 1, 2022 · a2c88f4 · a2c88f4
1 parent 6765ea4
commit a2c88f4
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Showing 3 changed files with 35 additions and 10 deletions.
diff --git a/src/Type/Php/RoundFunctionReturnTypeExtension.php b/src/Type/Php/RoundFunctionReturnTypeExtension.php
@@ -5,10 +5,12 @@
 use PhpParser\Node\Expr\FuncCall;
 use PHPStan\Analyser\Scope;
 use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\BenevolentUnionType;
 use PHPStan\Type\Constant\ConstantBooleanType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
 use PHPStan\Type\FloatType;
 use PHPStan\Type\IntegerType;
+use PHPStan\Type\MixedType;
 use PHPStan\Type\NeverType;
 use PHPStan\Type\NullType;
 use PHPStan\Type\Type;
@@ -31,28 +33,45 @@ public function isFunctionSupported(FunctionReflection $functionReflection): boo
 
 	public function getTypeFromFunctionCall(FunctionReflection $functionReflection, FuncCall $functionCall, Scope $scope): Type
 	{
-		$defaultReturnType = new FloatType();
+		if (PHP_VERSION_ID >= 80000) {
+			// PHP 8 fatals with a missing parameter.
+			$noArgsReturnType = new NeverType(true);
+			// PHP 7 can return either a float or fatal.
+			$defaultReturnType = new BenevolentUnionType([
+				new FloatType(),
+				new NeverType(true),
+			]);
+		} else {
+			// PHP 7 returns null with a missing parameter.
+			$noArgsReturnType = new NullType();
+			// PHP 7 can return either a float or false.
+			$defaultReturnType = new BenevolentUnionType([
+				new FloatType(),
+				new ConstantBooleanType(false),
+			]);
+		}
+
 		if (count($functionCall->getArgs()) < 1) {
-			if (PHP_VERSION_ID >= 80000) {
-				return new NeverType(true);
-			} else {
-				return new NullType();
-			}
+			return $noArgsReturnType;
 		}
 
 		$firstArgType = $scope->getType($functionCall->getArgs()[0]->value);
 
+		if ($firstArgType instanceof MixedType) {
+			return $defaultReturnType;
+		}
+
 		if (PHP_VERSION_ID >= 80000) {
 			if (!($firstArgType instanceof IntegerType) && !($firstArgType instanceof FloatType)) {
+				// PHP 8 fatals if the parameter is not an integer or float.
 				return new NeverType(true);
 			}
-		}
-
-		if ($firstArgType->isArray()->yes()) {
+		} elseif ($firstArgType->isArray()->yes()) {
+			// PHP 7 returns false if the parameter is an array.
 			return new ConstantBooleanType(false);
 		}
 
-		return $defaultReturnType;
+		return new FloatType();
 	}
 
 }
diff --git a/tests/PHPStan/Analyser/data/round-php8.php b/tests/PHPStan/Analyser/data/round-php8.php
@@ -17,6 +17,7 @@
 assertType('*NEVER*', round(array()));
 assertType('*NEVER*', round(array(123)));
 assertType('*NEVER*', round());
+assertType('(*NEVER*|float)', round($_GET['foo']));
 
 // Ceil
 assertType('float', ceil(123));
@@ -31,6 +32,7 @@
 assertType('*NEVER*', ceil(array()));
 assertType('*NEVER*', ceil(array(123)));
 assertType('*NEVER*', ceil());
+assertType('(*NEVER*|float)', ceil($_GET['foo']));
 
 // Floor
 assertType('float', floor(123));
@@ -45,3 +47,4 @@
 assertType('*NEVER*', floor(array()));
 assertType('*NEVER*', floor(array(123)));
 assertType('*NEVER*', floor());
+assertType('(*NEVER*|float)', floor($_GET['foo']));
diff --git a/tests/PHPStan/Analyser/data/round.php b/tests/PHPStan/Analyser/data/round.php
@@ -17,6 +17,7 @@
 assertType('false', round(array()));
 assertType('false', round(array(123)));
 assertType('null', round());
+assertType('(float|false)', round($_GET['foo']));
 
 // Ceil
 assertType('float', ceil(123));
@@ -31,6 +32,7 @@
 assertType('false', ceil(array()));
 assertType('false', ceil(array(123)));
 assertType('null', ceil());
+assertType('(float|false)', ceil($_GET['foo']));
 
 // Floor
 assertType('float', floor(123));
@@ -45,3 +47,4 @@
 assertType('false', floor(array()));
 assertType('false', floor(array(123)));
 assertType('null', floor());
+assertType('(float|false)', floor($_GET['foo']));