diff --git a/CHANGELOG.md b/CHANGELOG.md
index e12d7068..8b76ed57 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # CHANGELOG
 
+## 1.0.20 - 2019-03-13
+- Improve Tests.
+- Update Docs.
+
+
 ## 1.0.19 - 2019-03-12
 - Add SSL Verify Option `verify()`.
 
diff --git a/src/AlibabaCloud.php b/src/AlibabaCloud.php
index 54c3d1bb..0768e1af 100644
--- a/src/AlibabaCloud.php
+++ b/src/AlibabaCloud.php
@@ -28,7 +28,7 @@ class AlibabaCloud
     /**
      * Version of the Client
      */
-    const VERSION = '1.0.19';
+    const VERSION = '1.0.20';
 
     /**
      * This static method can directly call the specific service.
diff --git a/tests/Unit/FunctionsTest.php b/tests/Unit/FunctionsTest.php
index 594cb51c..f3acb97a 100644
--- a/tests/Unit/FunctionsTest.php
+++ b/tests/Unit/FunctionsTest.php
@@ -62,4 +62,20 @@ public static function testString()
         self::assertEquals('"Alibaba Cloud', getenv('STRING'));
         self::assertEquals('"Alibaba Cloud', \AlibabaCloud\Client\env('STRING'));
     }
+
+    public static function testEnvNotEmpty()
+    {
+        self::assertFalse(\AlibabaCloud\Client\envNotEmpty('ALIBABA_CLOUD_NOT_EXISTS'));
+    }
+
+    /**
+     * @expectedException \AlibabaCloud\Client\Exception\ClientException
+     * @expectedExceptionMessage Environment variable 'ALIBABA_CLOUD_NOT_EXISTS' cannot be empty
+     */
+    public static function testEnvNotEmptyException()
+    {
+        putenv('ALIBABA_CLOUD_NOT_EXISTS=');
+
+        self::assertFalse(\AlibabaCloud\Client\envNotEmpty('ALIBABA_CLOUD_NOT_EXISTS'));
+    }
 }