Offset access on lowercase-string is lowercase-string

Author: staabm

tests/PHPStan/Analyser/nsrt/string-offsets.php

@@ -9,10 +9,11 @@
  * @param int<3, 10> $threeToTen
  * @param int<10, max> $tenOrMore
  * @param int<-10, -5> $negative
+ * @param lowercase-string $lowercase
  *
  * @return void
  */
-function doFoo($oneToThree, $threeToTen, $tenOrMore, $negative, int $i) {
+function doFoo($oneToThree, $threeToTen, $tenOrMore, $negative, int $i, string $lowercase) {
 	$s = "world";
 	if (rand(0, 1)) {
 		$s = "hello";
@@ -29,4 +30,6 @@ function doFoo($oneToThree, $threeToTen, $tenOrMore, $negative, int $i) {
 
 	$longString = "myF5HnJv799kWf8VRI7g97vwnABTwN9y2CzAVELCBfRqyqkdTzXg7BkGXcwuIOscAiT6tSuJGzVZOJnYXvkiKQzYBNjjkCPOzSKXR5YHRlVxV1BetqZz4XOmaH9mtacJ9azNYL6bNXezSBjX13BSZy02SK2udzQLbTPNQwlKadKaNkUxjtWegkb8QDFaXbzH1JENVSLVH0FYd6POBU82X1xu7FDDKYLzwsWJHBGVhG8iugjEGwLj22x5ViosUyKR";
 	assertType("non-empty-string", $longString[$i]);
+	
+	assertType("lowercase-string&non-empty-string", $lowercase[$i]);
 }