From 5b10396f488af68700819168d84e4de92f92cbd7 Mon Sep 17 00:00:00 2001
From: Svyatoslav Kuzmich <svyatoslav.kuzmich@jetbrains.com>
Date: Wed, 27 Oct 2021 22:16:10 +0300
Subject: [PATCH] [stdlib] Test that modification of the array returned by
 toCharArray() doesn't affect the original string

---
 libraries/stdlib/test/text/StringTest.kt | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/libraries/stdlib/test/text/StringTest.kt b/libraries/stdlib/test/text/StringTest.kt
index 5e8658f2fb6..a3a168fc01f 100644
--- a/libraries/stdlib/test/text/StringTest.kt
+++ b/libraries/stdlib/test/text/StringTest.kt
@@ -123,6 +123,19 @@ class StringTest {
         assertFailsWith<IndexOutOfBoundsException> { s.toCharArray(-1) }
         assertFailsWith<IndexOutOfBoundsException> { s.toCharArray(0, 6) }
         assertFailsWith<IllegalArgumentException> { s.toCharArray(3, 1) }
+
+        // Array modifications must not affect original string
+        val a = s.toCharArray()
+        for (i in a.indices) {
+            a[i] = ' '
+        }
+        assertContentEquals(charArrayOf(' ', ' ', ' ', ' ', ' '), a)
+        val a13 = s.toCharArray(1, 3)
+        for (i in a13.indices) {
+            a13[i] = ' '
+        }
+        assertContentEquals(charArrayOf(' ', ' '), a13)
+        assertEquals("hello", s)
     }
 
     @Test fun isEmptyAndBlank() = withOneCharSequenceArg { arg1 ->