From 1b2037c1c8094053f7a97c777a06fc071692d47b Mon Sep 17 00:00:00 2001
From: Markus Staab <maggus.staab@googlemail.com>
Date: Mon, 9 Sep 2024 15:08:41 +0200
Subject: [PATCH] test `@throws` tag

---
 .../Operators/InvalidBinaryOperationRule.php     | 16 ++++++++++++++++
 .../Rules/Operators/data/invalid-division.php    |  6 ++++++
 2 files changed, 22 insertions(+)

diff --git a/src/Rules/Operators/InvalidBinaryOperationRule.php b/src/Rules/Operators/InvalidBinaryOperationRule.php
index d771cfe7000..8e051a2fad5 100644
--- a/src/Rules/Operators/InvalidBinaryOperationRule.php
+++ b/src/Rules/Operators/InvalidBinaryOperationRule.php
@@ -124,6 +124,7 @@ public function processNode(Node $node, Scope $scope): array
 					|| $node instanceof Node\Expr\BinaryOp\Mod
 				)
 				&& !$this->isDivisionByZeroCaught($node)
+				&& !$this->hasDivisionByZeroThrowsTag($scope)
 			) {
 				$zeroType = new ConstantIntegerType(0);
 				if ($zeroType->isSuperTypeOf($rightType)->maybe()) {
@@ -169,4 +170,19 @@ private function isDivisionByZeroCaught(Node $node): bool
 		return $tryCatchType->isSuperTypeOf(new ObjectType(DivisionByZeroError::class))->yes();
 	}
 
+	private function hasDivisionByZeroThrowsTag(Scope $scope): bool
+	{
+		$function = $scope->getFunction();
+		if ($function === null) {
+			return false;
+		}
+
+		$throwsType = $function->getThrowType();
+		if ($throwsType === null) {
+			return false;
+		}
+
+		return $throwsType->isSuperTypeOf(new ObjectType(DivisionByZeroError::class))->yes();
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Operators/data/invalid-division.php b/tests/PHPStan/Rules/Operators/data/invalid-division.php
index cb19463fff5..99bcf76bf95 100644
--- a/tests/PHPStan/Rules/Operators/data/invalid-division.php
+++ b/tests/PHPStan/Rules/Operators/data/invalid-division.php
@@ -68,3 +68,9 @@ function (int $i, int $x): void {
 	}
 };
 
+/**
+ * @throws \DivisionByZeroError
+ */
+function throws(int $i, int $x) {
+	return $i / $x;
+};