Add dedup to strings (#52350)

* Add `dedup` to strings

* formatting

---------

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Support/Str.php

@@ -341,6 +341,18 @@ public static function convertCase(string $string, int $mode = MB_CASE_FOLD, ?st
         return mb_convert_case($string, $mode, $encoding);
     }
 
+    /**
+     * Replace consecutive instances of a given character with a single character in the given string.
+     *
+     * @param  string  $string
+     * @param  string  $character
+     * @return string
+     */
+    public static function deduplicate(string $string, string $character = ' ')
+    {
+        return preg_replace('/'.preg_quote($character, '/').'+/u', $character, $string);
+    }
+
     /**
      * Determine if a given string ends with a given substring.
      *

src/Illuminate/Support/Stringable.php

@@ -235,6 +235,17 @@ public function convertCase(int $mode = MB_CASE_FOLD, ?string $encoding = 'UTF-8
         return new static(Str::convertCase($this->value, $mode, $encoding));
     }
 
+    /**
+     * Replace consecutive instances of a given character with a single character.
+     *
+     * @param  string  $character
+     * @return static
+     */
+    public function deduplicate(string $character = ' ')
+    {
+        return new static(Str::deduplicate($this->value, $character));
+    }
+
     /**
      * Get the parent directory's path.
      *

tests/Support/SupportStrTest.php

@@ -400,6 +400,14 @@ public function testConvertCase()
         Str::convertCase('Hello', -1);
     }
 
+    public function testDedup()
+    {
+        $this->assertSame(' laravel php framework ', Str::deduplicate(' laravel   php  framework '));
+        $this->assertSame('what', Str::deduplicate('whaaat', 'a'));
+        $this->assertSame('/some/odd/path/', Str::deduplicate('/some//odd//path/', '/'));
+        $this->assertSame('ムだム', Str::deduplicate('ムだだム', 'だ'));
+    }
+
     public function testParseCallback()
     {
         $this->assertEquals(['Class', 'method'], Str::parseCallback('Class@method'));

tests/Support/SupportStringableTest.php

@@ -212,6 +212,14 @@ public function testWhenContainsAll()
         }));
     }
 
+    public function testDedup()
+    {
+        $this->assertSame(' laravel php framework ', (string) $this->stringable(' laravel   php  framework ')->deduplicate());
+        $this->assertSame('what', (string) $this->stringable('whaaat')->deduplicate('a'));
+        $this->assertSame('/some/odd/path/', (string) $this->stringable('/some//odd//path/')->deduplicate('/'));
+        $this->assertSame('ムだム', (string) $this->stringable('ムだだム')->deduplicate('だ'));
+    }
+
     public function testDirname()
     {
         $this->assertSame('/framework/tests', (string) $this->stringable('/framework/tests/Support')->dirname());