From 9fdc774e7c3fc41a9381c26ca424a4569bb8af10 Mon Sep 17 00:00:00 2001
From: Vincent Langlet <vincentlanglet@hotmail.fr>
Date: Sat, 25 Oct 2025 15:20:14 +0200
Subject: [PATCH 1/2] Report unknown parameter for implicit variadic methods

---
 src/Rules/FunctionCallParametersCheck.php     |  4 ++-
 .../CallToFunctionParametersRuleTest.php      | 15 +++++++++++
 .../Rules/Functions/data/bug-13719.php        | 25 +++++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 tests/PHPStan/Rules/Functions/data/bug-13719.php

diff --git a/src/Rules/FunctionCallParametersCheck.php b/src/Rules/FunctionCallParametersCheck.php
index 57ae028018..5c3821aa4f 100644
--- a/src/Rules/FunctionCallParametersCheck.php
+++ b/src/Rules/FunctionCallParametersCheck.php
@@ -562,11 +562,13 @@ private function processArguments(
 		$originalParametersByName = [];
 		$unusedParametersByName = [];
 		$errors = [];
+		$isNativelyVariadic = false;
 		foreach ($parameters as $i => $parameter) {
 			$parametersByName[$parameter->getName()] = $parameter;
 			$originalParametersByName[$parameter->getName()] = $originalParameters[$i];
 
 			if ($parameter->isVariadic()) {
+				$isNativelyVariadic = true;
 				continue;
 			}
 
@@ -603,7 +605,7 @@ private function processArguments(
 
 				$parametersCount = count($parameters);
 				if (
-					!$parametersAcceptor->isVariadic()
+					!$isNativelyVariadic
 					|| $parametersCount <= 0
 					|| $isBuiltin
 				) {
diff --git a/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php b/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
index 41a04a2420..e5c6c94bec 100644
--- a/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
+++ b/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
@@ -534,6 +534,21 @@ public function testBug4514(): void
 		$this->analyse([__DIR__ . '/data/bug-4514.php'], []);
 	}
 
+	#[RequiresPhp('>= 8.0')]
+	public function testBug13719(): void
+	{
+		$this->analyse([__DIR__ . '/data/bug-13719.php'], [
+			[
+				'Unknown parameter $greetings in call to function non_variadic.',
+				18,
+			],
+			[
+				'Unknown parameter $greetings in call to function implicit_variadic.',
+				25,
+			],
+		]);
+	}
+
 	public function testBug4530(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-4530.php'], []);
diff --git a/tests/PHPStan/Rules/Functions/data/bug-13719.php b/tests/PHPStan/Rules/Functions/data/bug-13719.php
new file mode 100644
index 0000000000..de69633f52
--- /dev/null
+++ b/tests/PHPStan/Rules/Functions/data/bug-13719.php
@@ -0,0 +1,25 @@
+<?php declare(strict_types = 1);
+
+function non_variadic(string $name, ?string $greeting = null): void {
+	var_dump($name);
+}
+
+// Explicitly defined with variadic arguments.
+function explicit_variadic(string $name, ?string $greeting = null, string ...$args): void {
+	var_dump($name);
+}
+
+// Treated as variadic due to usage of `func_get_args()`.
+function implicit_variadic(string $name, ?string $greeting = null): void {
+	var_dump(func_get_args());
+}
+
+// PHPStan correctly detects the error ('greetings' vs 'greeting').
+non_variadic('my name', greetings: 'my greeting');
+
+// PHPStan correctly doesn't report anything since the function
+// accepts variadic arguments and this is not an error.
+explicit_variadic('my name', greetings: 'my greeting');
+
+// ISSUE: PHPStan should detect argument.unknown error here, but it doesn't.
+implicit_variadic('my name', greetings: 'my greeting');

From 11fb8368f69e3554f8ca7280c266e4294fdbe74d Mon Sep 17 00:00:00 2001
From: Vincent Langlet <vincentlanglet@hotmail.fr>
Date: Sat, 25 Oct 2025 17:40:39 +0200
Subject: [PATCH 2/2] Fix namespace

---
 .../Rules/Functions/CallToFunctionParametersRuleTest.php  | 8 ++++----
 tests/PHPStan/Rules/Functions/data/bug-13719.php          | 2 ++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php b/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
index e5c6c94bec..b179c1ff0d 100644
--- a/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
+++ b/tests/PHPStan/Rules/Functions/CallToFunctionParametersRuleTest.php
@@ -539,12 +539,12 @@ public function testBug13719(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-13719.php'], [
 			[
-				'Unknown parameter $greetings in call to function non_variadic.',
-				18,
+				'Unknown parameter $greetings in call to function Bug13719\non_variadic.',
+				20,
 			],
 			[
-				'Unknown parameter $greetings in call to function implicit_variadic.',
-				25,
+				'Unknown parameter $greetings in call to function Bug13719\implicit_variadic.',
+				27,
 			],
 		]);
 	}
diff --git a/tests/PHPStan/Rules/Functions/data/bug-13719.php b/tests/PHPStan/Rules/Functions/data/bug-13719.php
index de69633f52..8a33eb50f3 100644
--- a/tests/PHPStan/Rules/Functions/data/bug-13719.php
+++ b/tests/PHPStan/Rules/Functions/data/bug-13719.php
@@ -1,5 +1,7 @@
 <?php declare(strict_types = 1);
 
+namespace Bug13719;
+
 function non_variadic(string $name, ?string $greeting = null): void {
 	var_dump($name);
 }