Implemented mechanism enabling developers to overwrite existing confi…

…guration settings.

src/Payfast.php

@@ -54,17 +54,24 @@ class Payfast implements PaymentProcessor
 
     protected $payment_method;
 
+    protected $passphrase;
 
     public function __construct()
     {
         $this->merchant = config('payfast.merchant');
+        $this->passphrase = config('payfast.passphrase');
     }
 
     public function getMerchant()
     {
         return $this->merchant;
     }
 
+    public function setMerchant(array $merchant)
+    {
+        $this->merchant = $merchant;
+    }
+
     public function setBuyer($first, $last, $email)
     {
         $this->buyer = [
@@ -74,6 +81,11 @@ public function setBuyer($first, $last, $email)
         ];
     }
 
+    public function setPassphrase(string $passphrase)
+    {
+        $this->passphrase = $passphrase;
+    }
+
     public function setMerchantReference($reference)
     {
         $this->merchantReference = $reference;
@@ -132,9 +144,9 @@ public function buildQueryString()
             }
         }
         $this->output = substr( $this->output, 0, -1 );
-        if( isset( $passPhrase ) )
+        if( !empty( $this->passphrase ) )
         {
-            $this->output .= '&passphrase='.$passPhrase;
+            $this->output .= '&passphrase=' . $this->passphrase;
         }
     }