1 files changed, 45 insertions, 1 deletions

diff --git a/tests/UtilsTest.php b/tests/UtilsTest.php
index c885f552..e70cc1ae 100644
--- a/tests/UtilsTest.php
+++ b/tests/UtilsTest.php
@@ -23,7 +23,12 @@ class UtilsTest extends PHPUnit_Framework_TestCase
 
     // Expected log date format
     protected static $dateFormat = 'Y/m/d H:i:s';
-    
+
+    /**
+     * @var string Save the current timezone.
+     */
+    protected static $defaultTimeZone;
+
 
     /**
      * Assign reference data
@@ -31,6 +36,17 @@ class UtilsTest extends PHPUnit_Framework_TestCase
     public static function setUpBeforeClass()
     {
         self::$sidHashes = ReferenceSessionIdHashes::getHashes();
+        self::$defaultTimeZone = date_default_timezone_get();
+        // Timezone without DST for test consistency
+        date_default_timezone_set('Africa/Nairobi');
+    }
+
+    /**
+     * Reset the timezone
+     */
+    public static function tearDownAfterClass()
+    {
+        date_default_timezone_set(self::$defaultTimeZone);
     }
 
     /**
@@ -282,4 +298,32 @@ class UtilsTest extends PHPUnit_Framework_TestCase
         $this->assertEquals('', normalize_spaces(''));
         $this->assertEquals(null, normalize_spaces(null));
     }
+
+    /**
+     * Test arrays_combine
+     */
+    public function testCartesianProductGenerator()
+    {
+        $arr = [['ab', 'cd'], ['ef', 'gh'], ['ij', 'kl'], ['m']];
+        $expected = [
+            ['ab', 'ef', 'ij', 'm'],
+            ['ab', 'ef', 'kl', 'm'],
+            ['ab', 'gh', 'ij', 'm'],
+            ['ab', 'gh', 'kl', 'm'],
+            ['cd', 'ef', 'ij', 'm'],
+            ['cd', 'ef', 'kl', 'm'],
+            ['cd', 'gh', 'ij', 'm'],
+            ['cd', 'gh', 'kl', 'm'],
+        ];
+        $this->assertEquals($expected, iterator_to_array(cartesian_product_generator($arr)));
+    }
+
+    /**
+     * Test date_format() with invalid parameter.
+     */
+    public function testDateFormatInvalid()
+    {
+        $this->assertFalse(format_date([]));
+        $this->assertFalse(format_date(null));
+    }
 }