Some tests for crypt_random_string().

tests/Unit/Crypt/RandomTest.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * @author    Andreas Fischer <bantu@phpbb.com>
+ * @copyright MMXIV Andreas Fischer
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ */
+
+class Unit_Crypt_RandomTest extends PhpseclibTestCase
+{
+    public function stringLengthData()
+    {
+        return array_map(array($this, 'wrap'), array(
+            1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 17, 19, 20, 23, 29, 31, 37,
+            41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 111, 128, 1000,
+            1024, 10000, 12345, 100000, 123456
+        ));
+    }
+
+    /** @dataProvider stringLengthData */
+    public function testStringLength($length)
+    {
+        $this->assertSame(
+            $length,
+            strlen(crypt_random_string($length)),
+            'Failed asserting that a string of expected length was generated.'
+        );
+    }
+
+    /**
+    * Takes a set of random values of length 128 bits and asserts all taken
+    * values are unique.
+    */
+    public function testStringUniqueness()
+    {
+        $values = array();
+        for ($i = 0; $i < 10000; ++$i) {
+            $rand = crypt_random_string(16);
+            $this->assertSame(16, strlen($rand));
+            $this->assertFalse(
+                isset($values[$rand]),
+                'Failed asserting that generated value does not exist in set.'
+            );
+            $values[$rand] = true;
+        }
+    }
+
+    protected function wrap($x)
+    {
+        // array() is not a function, but $this->wrap() is.
+        return array($x);
+    }
+}