Add test for 'testAddDay', 'testSubDay', 'testGetLastWeek' and 'testGetLastMonth' methods

Author: majidalaeinia

tests/JalalianTest.php

@@ -205,4 +205,28 @@ public function testGetFirstDayOfYear()
         $jDate = new Jalalian(1393, 9, 5);
         $this->assertEquals($jDate->getFirstDayOfYear()->format('Y-m-d'), '1393-01-01');
     }
+
+    public function testAddDay()
+    {
+        $jDate = new Jalalian(1401, 6, 31);
+        $this->assertEquals($jDate->addDay()->format('Y-m-d'), '1401-07-01');
+    }
+
+    public function testSubDay()
+    {
+        $jDate = new Jalalian(1401, 6, 1);
+        $this->assertEquals($jDate->subDay()->format('Y-m-d'), '1401-05-31');
+    }
+
+    public function testGetLastWeek()
+    {
+        $jDate = new Jalalian(1401, 6, 8);
+        $this->assertEquals($jDate->getLastWeek()->format('Y-m-d'), '1401-06-01');
+    }
+
+    public function testGetLastMonth()
+    {
+        $jDate = new Jalalian(1401, 6, 8);
+        $this->assertEquals($jDate->getLastMonth()->format('Y-m-d'), '1401-05-08');
+    }
 }