From c369598b05e95380d173027c1d458e4ab33dcabb Mon Sep 17 00:00:00 2001
From: Thomas Calvet <calvet.thomas@gmail.com>
Date: Mon, 23 Dec 2019 17:36:34 +0100
Subject: [PATCH] [String] Add the reverse method

---
 .../Component/String/AbstractString.php       |  5 +++++
 .../String/AbstractUnicodeString.php          | 11 +++++++++++
 src/Symfony/Component/String/ByteString.php   | 11 +++++++++++
 src/Symfony/Component/String/CHANGELOG.md     |  5 +++++
 .../String/Tests/AbstractAsciiTestCase.php    | 19 +++++++++++++++++++
 .../String/Tests/AbstractUnicodeTestCase.php  | 12 ++++++++++++
 6 files changed, 63 insertions(+)

diff --git a/src/Symfony/Component/String/AbstractString.php b/src/Symfony/Component/String/AbstractString.php
index e56697e391549..ec981176d25d8 100644
--- a/src/Symfony/Component/String/AbstractString.php
+++ b/src/Symfony/Component/String/AbstractString.php
@@ -467,6 +467,11 @@ abstract public function replace(string $from, string $to): self;
      */
     abstract public function replaceMatches(string $fromRegexp, $to): self;
 
+    /**
+     * @return static
+     */
+    abstract public function reverse(): self;
+
     /**
      * @return static
      */
diff --git a/src/Symfony/Component/String/AbstractUnicodeString.php b/src/Symfony/Component/String/AbstractUnicodeString.php
index 19ad5e8939d95..fed79e2f536a0 100644
--- a/src/Symfony/Component/String/AbstractUnicodeString.php
+++ b/src/Symfony/Component/String/AbstractUnicodeString.php
@@ -342,6 +342,17 @@ public function replaceMatches(string $fromRegexp, $to): parent
         return $str;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function reverse(): parent
+    {
+        $str = clone $this;
+        $str->string = implode('', array_reverse(preg_split('/(\X)/u', $str->string, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY)));
+
+        return $str;
+    }
+
     public function snake(): parent
     {
         $str = $this->camel()->title();
diff --git a/src/Symfony/Component/String/ByteString.php b/src/Symfony/Component/String/ByteString.php
index d831940e16b07..ab44882ceade1 100644
--- a/src/Symfony/Component/String/ByteString.php
+++ b/src/Symfony/Component/String/ByteString.php
@@ -303,6 +303,17 @@ public function replaceMatches(string $fromRegexp, $to): parent
         return $str;
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function reverse(): parent
+    {
+        $str = clone $this;
+        $str->string = strrev($str->string);
+
+        return $str;
+    }
+
     public function slice(int $start = 0, int $length = null): parent
     {
         $str = clone $this;
diff --git a/src/Symfony/Component/String/CHANGELOG.md b/src/Symfony/Component/String/CHANGELOG.md
index 28b9c6254196b..050c734f8982d 100644
--- a/src/Symfony/Component/String/CHANGELOG.md
+++ b/src/Symfony/Component/String/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+5.1.0
+-----
+
+ * Added the `AbstractString::reverse()` method.
+
 5.0.0
 -----
 
diff --git a/src/Symfony/Component/String/Tests/AbstractAsciiTestCase.php b/src/Symfony/Component/String/Tests/AbstractAsciiTestCase.php
index 934b29c1486bd..c7be84faabef3 100644
--- a/src/Symfony/Component/String/Tests/AbstractAsciiTestCase.php
+++ b/src/Symfony/Component/String/Tests/AbstractAsciiTestCase.php
@@ -1377,4 +1377,23 @@ public function testToString()
 
         self::assertSame('foobar', $instance->toString());
     }
+
+    /**
+     * @dataProvider provideReverse
+     */
+    public function testReverse(string $expected, string $origin)
+    {
+        $instance = static::createFromString($origin)->reverse();
+
+        $this->assertEquals(static::createFromString($expected), $instance);
+    }
+
+    public static function provideReverse()
+    {
+        return [
+            ['', ''],
+            ['oof', 'foo'],
+            ["\n!!!\tTAERG SI     ynofmyS    ", "    Symfony     IS GREAT\t!!!\n"],
+        ];
+    }
 }
diff --git a/src/Symfony/Component/String/Tests/AbstractUnicodeTestCase.php b/src/Symfony/Component/String/Tests/AbstractUnicodeTestCase.php
index 173abd026a026..84e64b02e9f6a 100644
--- a/src/Symfony/Component/String/Tests/AbstractUnicodeTestCase.php
+++ b/src/Symfony/Component/String/Tests/AbstractUnicodeTestCase.php
@@ -568,4 +568,16 @@ public static function providePadStart(): array
             ]
         );
     }
+
+    public static function provideReverse()
+    {
+        return array_merge(
+            parent::provideReverse(),
+            [
+                ['äuß⭐erst', 'tsre⭐ßuä'],
+                ['漢字ーユニコードéèΣσς', 'ςσΣèéドーコニユー字漢'],
+                ['नमस्ते', 'तेस्मन'],
+            ]
+        );
+    }
 }