From de192104926ca026867a4a7bea46907c32b426ad Mon Sep 17 00:00:00 2001
From: sc0Vu <alk03073135@gmail.com>
Date: Fri, 22 Dec 2017 18:07:31 +0800
Subject: [PATCH] isZeroPrefixed

---
 src/Utils.php           | 16 +++++++++++++++-
 test/unit/UtilsTest.php | 16 ++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/Utils.php b/src/Utils.php
index 2cad45a..22e4157 100644
--- a/src/Utils.php
+++ b/src/Utils.php
@@ -69,6 +69,20 @@ class Utils
         return pack('H*', $value);
     }
 
+    /**
+     * isZeroPrefixed
+     * 
+     * @param string
+     * @return bool
+     */
+    public static function isZeroPrefixed($value)
+    {
+        if (!is_string($value)) {
+            throw new InvalidArgumentException('The value to zeroPrefixed function must be string.');
+        }
+        return (strpos($value, '0x') === 0);
+    }
+
     /**
      * sha3
      * keccak256
@@ -90,5 +104,5 @@ class Utils
             return null;
         }
         return '0x' . $hash;
-    }
+    }    
 }
\ No newline at end of file
diff --git a/test/unit/UtilsTest.php b/test/unit/UtilsTest.php
index 6b5c3b7..a95d1be 100644
--- a/test/unit/UtilsTest.php
+++ b/test/unit/UtilsTest.php
@@ -63,6 +63,22 @@ class UtilsTest extends TestCase
         $this->assertEquals($str, '七彩神仙鱼');
     }
 
+    /**
+     * testIsZeroPrefixed
+     * 
+     * @return void
+     */
+    public function testIsZeroPrefixed()
+    {
+        $isPrefixed = Utils::isZeroPrefixed($this->testHex);
+
+        $this->assertEquals($isPrefixed, false);
+
+        $isPrefixed = Utils::isZeroPrefixed('0x' . $this->testHex);
+
+        $this->assertEquals($isPrefixed, true);
+    }
+
     /**
      * testSha3
      *