Support named arguments after unpacking

src/Php/PhpVersions.php

@@ -38,4 +38,9 @@ public function supportsNamedArguments(): TrinaryLogic
 		return IntegerRangeType::fromInterval(80000, null)->isSuperTypeOf($this->phpVersions)->result;
 	}
 
+	public function supportsNamedArgumentAfterUnpackedArgument(): TrinaryLogic
+	{
+		return IntegerRangeType::fromInterval(80100, null)->isSuperTypeOf($this->phpVersions)->result;
+	}
+
 }

src/Rules/FunctionCallParametersCheck.php

@@ -93,14 +93,22 @@ public function check(
 			$functionParametersMaxCount = -1;
 		}
 
-		/** @var array<int, array{Expr, Type|null, bool, string|null, int}> $arguments */
+		/** @var array<int, array{Expr, Type|null, bool, string|null, int, bool}> $arguments */
 		$arguments = [];
 		/** @var array<int, Node\Arg> $args */
 		$args = $funcCall->getArgs();
 		$hasNamedArguments = false;
 		$hasUnpackedArgument = false;
 		$errors = [];
 		foreach ($args as $arg) {
+			$argumentName = null;
+			if ($arg->name !== null) {
+				$hasNamedArguments = true;
+				$argumentName = $arg->name->toString();
+			}
+
+			$nonUnpackAfterUnpacked = false;
+
 			if ($hasNamedArguments && $arg->unpack) {
 				$errors[] = RuleErrorBuilder::message('Named argument cannot be followed by an unpacked (...) argument.')
 					->identifier('argument.unpackAfterNamed')
@@ -109,20 +117,19 @@ public function check(
 					->build();
 			}
 			if ($hasUnpackedArgument && !$arg->unpack) {
-				$errors[] = RuleErrorBuilder::message('Unpacked argument (...) cannot be followed by a non-unpacked argument.')
-					->identifier('argument.nonUnpackAfterUnpacked')
-					->line($arg->getStartLine())
-					->nonIgnorable()
-					->build();
+				$nonUnpackAfterUnpacked = true;
+
+				if ($argumentName === null || !$scope->getPhpVersion()->supportsNamedArgumentAfterUnpackedArgument()->yes()) {
+					$errors[] = RuleErrorBuilder::message('Unpacked argument (...) cannot be followed by a non-unpacked argument.')
+						->identifier('argument.nonUnpackAfterUnpacked')
+						->line($arg->getStartLine())
+						->nonIgnorable()
+						->build();
+				}
 			}
 			if ($arg->unpack) {
 				$hasUnpackedArgument = true;
 			}
-			$argumentName = null;
-			if ($arg->name !== null) {
-				$hasNamedArguments = true;
-				$argumentName = $arg->name->toString();
-			}
 			if ($arg->unpack) {
 				$type = $scope->getType($arg->value);
 				$arrays = $type->getConstantArrays();
@@ -176,6 +183,7 @@ public function check(
 							false,
 							$keyArgumentName,
 							$arg->getStartLine(),
+							$nonUnpackAfterUnpacked,
 						];
 					}
 				} else {
@@ -185,6 +193,7 @@ public function check(
 						true,
 						null,
 						$arg->getStartLine(),
+						$nonUnpackAfterUnpacked,
 					];
 				}
 				continue;
@@ -196,6 +205,7 @@ public function check(
 				false,
 				$argumentName,
 				$arg->getStartLine(),
+				$nonUnpackAfterUnpacked,
 			];
 		}
 
@@ -547,7 +557,7 @@ private function processArguments(
 		$newArguments = [];
 
 		$namedArgumentAlreadyOccurred = false;
-		foreach ($arguments as $i => [$argumentValue, $argumentValueType, $unpack, $argumentName, $argumentLine]) {
+		foreach ($arguments as $i => [$argumentValue, $argumentValueType, $unpack, $argumentName, $argumentLine, $nonUnpackAfterUnpacked]) {
 			if ($argumentName === null) {
 				if (!isset($parameters[$i])) {
 					if (!$parametersAcceptor->isVariadic() || count($parameters) === 0) {
@@ -607,10 +617,19 @@ private function processArguments(
 				&& !$parameter->isVariadic()
 				&& !array_key_exists($parameter->getName(), $unusedParametersByName)
 			) {
-				$errors[] = RuleErrorBuilder::message(sprintf('Argument for parameter $%s has already been passed.', $parameter->getName()))
-					->identifier('argument.duplicate')
-					->line($argumentLine)
-					->build();
+				if ($nonUnpackAfterUnpacked) {
+					$errors[] = RuleErrorBuilder::message(sprintf('Named parameter cannot overwrite already unpacked argument $%s.', $parameter->getName()))
+						->identifier('argument.namedOverwriteAfterUnpacked')
+						->line($argumentLine)
+						->nonIgnorable()
+						->build();
+				} else {
+					$errors[] = RuleErrorBuilder::message(sprintf('Argument for parameter $%s has already been passed.', $parameter->getName()))
+						->identifier('argument.duplicate')
+						->line($argumentLine)
+						->build();
+				}
+
 				continue;
 			}
 

tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php

@@ -499,6 +499,20 @@ public function testNamedArguments(): void
 		$this->analyse([__DIR__ . '/data/named-arguments.php'], $errors);
 	}
 
+	public function testNamedArgumentsAfterUnpacking(): void
+	{
+		if (PHP_VERSION_ID < 80100) {
+			$this->markTestSkipped('Test requires PHP 8.1.');
+		}
+
+		$this->analyse([__DIR__ . '/data/named-arguments-after-unpacking.php'], [
+			[
+				'Named parameter cannot overwrite already unpacked argument $b.',
+				14,
+			],
+		]);
+	}
+
 	public function testBug4514(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-4514.php'], []);
@@ -1936,4 +1950,13 @@ public function testBug12051(): void
 		$this->analyse([__DIR__ . '/data/bug-12051.php'], []);
 	}
 
+	public function testBug11418(): void
+	{
+		if (PHP_VERSION_ID < 80100) {
+			$this->markTestSkipped('Test requires PHP 8.1.');
+		}
+
+		$this->analyse([__DIR__ . '/data/bug-11418.php'], []);
+	}
+
 }

tests/PHPStan/Rules/Functions/data/bug-11418.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Bug11418;
+
+function foo(int $a, int $b, int $c = 3, int $d = 4): int {
+	return $a + $b + $c + $d;
+}
+
+var_dump(foo(...[1, 2], d: 40)); // 46

tests/PHPStan/Rules/Functions/data/named-arguments-after-unpacking.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace FunctionNamedArgumentsAfterUnpacking;
+
+// https://www.php.net/manual/en/functions.arguments.php#example-180
+
+function foo($a, $b, $c = 3, $d = 4) {
+	return $a + $b + $c + $d;
+}
+
+var_dump(foo(...[1, 2], d: 40)); // 46
+var_dump(foo(...['b' => 2, 'a' => 1], d: 40)); // 46
+
+var_dump(foo(...[1, 2], b: 20)); // Fatal error. Named parameter $b overwrites previous argument