Fixes exponentiation operator

.gitignore

@@ -1,2 +1,3 @@
 vendor/
 .idea/
+composer.lock

bin/phpunit

@@ -0,0 +1 @@
+../vendor/phpunit/phpunit/phpunit

composer.json

@@ -11,7 +11,16 @@
             "email": "frei@neonxp.info"
         }
     ],
+    "require": {
+        "php": ">=5.6"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "~5.0"
+    },
     "autoload": {
         "psr-0": {"NXP": "src/"}
+    },
+    "config": {
+        "bin-dir": "bin"
     }
 }

src/NXP/Classes/Token/TokenDegree.php

@@ -41,13 +41,13 @@ class TokenDegree extends AbstractOperator
 
     /**
      * @param InterfaceToken[] $stack
-     * @return $this
+     * @return TokenNumber
      */
     public function execute(&$stack)
     {
         $op2 = array_pop($stack);
         $op1 = array_pop($stack);
-        $result = $op1->getValue() ^ $op2->getValue();
+        $result = $op1->getValue() ** $op2->getValue();
 
         return new TokenNumber($result);
     }

tests/MathTest.php

@@ -33,6 +33,12 @@ class MathTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals($calculator->execute('1 / 0'), 0);
     }
 
+    public function testExponentiation()
+    {
+        $calculator = new MathExecutor();
+        $this->assertEquals($calculator->execute('10 ^ 2'), 100);
+    }
+
     /**
      * Expressions data provider
      */