generateUUID added

Author: SmetDenis

README.md

@@ -538,6 +538,9 @@ Str::esc($string)
 
 // Convert camel case to human readable format
 Str::splitCamelCase($input, $separator = '_', $toLower = true)
+
+// Generates a universally unique identifier (UUID v4) according to RFC 4122
+Str::generateUUID()
 ```
 
 

src/Str.php

@@ -693,4 +693,43 @@ public static function splitCamelCase($input, $separator = '_', $toLower = true)
 
         return $output;
     }
+
+    /**
+     * Generates a universally unique identifier (UUID v4) according to RFC 4122
+     * Version 4 UUIDs are pseudo-random!
+     *
+     * Returns Version 4 UUID format: xxxxxxxx-xxxx-4xxx-Yxxx-xxxxxxxxxxxx where x is
+     * any random hex digit and Y is a random choice from 8, 9, a, or b.
+     *
+     * @see http://stackoverflow.com/questions/2040240/php-function-to-generate-v4-uuid
+     *
+     * @return string
+     */
+    public static function generateUUID()
+    {
+        return sprintf(
+            '%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
+
+            // 32 bits for "time_low"
+            mt_rand(0, 0xffff),
+            mt_rand(0, 0xffff),
+
+            // 16 bits for "time_mid"
+            mt_rand(0, 0xffff),
+
+            // 16 bits for "time_hi_and_version",
+            // four most significant bits holds version number 4
+            mt_rand(0, 0x0fff) | 0x4000,
+
+            // 16 bits, 8 bits for "clk_seq_hi_res",
+            // 8 bits for "clk_seq_low",
+            // two most significant bits holds zero and one for variant DCE1.1
+            mt_rand(0, 0x3fff) | 0x8000,
+
+            // 48 bits for "node"
+            mt_rand(0, 0xffff),
+            mt_rand(0, 0xffff),
+            mt_rand(0, 0xffff)
+        );
+    }
 }

tests/StringTest.php

@@ -225,4 +225,9 @@ public function testSplitCamelCase()
         isSame('word number', Str::splitCamelCase('wordNumber', ' '));
         isSame('word Number', Str::splitCamelCase('wordNumber', ' ', false));
     }
+
+    public function testGenerateUUID()
+    {
+        isNotSame(Str::generateUUID(), Str::generateUUID());
+    }
 }