fix

Author: staabm

src/Analyser/TypeSpecifier.php

@@ -694,8 +694,11 @@ public function specifyTypesInCondition(
 					&& in_array($expr->expr->name->toLowerString(), ['array_rand'], true)
 					&& count($expr->expr->getArgs()) >= 1
 				) {
+					$numArg = null;
 					$arrayArg = $expr->expr->getArgs()[0]->value;
-					$numArg = $expr->expr->getArgs()[1]->value;
+					if (count($expr->expr->getArgs()) > 1) {
+						$numArg = $expr->expr->getArgs()[1]->value;
+					}
 					$one = new ConstantIntegerType(1);
 					$arrayType = $scope->getType($arrayArg);
 

src/Rules/Arrays/NonexistentOffsetInArrayDimFetchRule.php

@@ -136,11 +136,14 @@ public function processNode(Node $node, Scope $scope): array
 			&& $node->dim->name->toLowerString() === 'array_rand'
 			&& count($node->dim->getArgs()) >= 1
 		) {
+			$numArg = null;
 			$arrayArg = $node->dim->getArgs()[0]->value;
-			$numArg = $node->dim->getArgs()[1]->value;
-
+			if (count($node->dim->getArgs()) > 1) {
+				$numArg = $node->dim->getArgs()[1]->value;
+			}
 			$one = new ConstantIntegerType(1);
 			$arrayType = $scope->getType($arrayArg);
+
 			if (
 				$arrayArg instanceof Node\Expr\Variable
 				&& $node->var instanceof Node\Expr\Variable

tests/PHPStan/Rules/Arrays/NonexistentOffsetInArrayDimFetchRuleTest.php

@@ -949,16 +949,15 @@ public function testBug12981(): void
 		$this->analyse([__DIR__ . '/data/bug-12981.php'], [
 			[
 				'Offset array<int, int|string> might not exist on non-empty-array<bool|float|int|string>.',
-				31
+				31,
 			],
 			[
 				'Offset array<int, int|string> might not exist on non-empty-array<bool|float|int|string>.',
-				33
+				33,
 			],
 		]);
 	}
 
-
 	public function testBugObject(): void
 	{
 		$this->analyse([__DIR__ . '/data/bug-object.php'], [