Fixed two tests (pow & Infinite)

Author: castarco

src/InfiniteDecimal.php

@@ -188,12 +188,22 @@ public function pow(Decimal $b, $scale = null)
                 throw new \DomainException("Negative infinite elevated to infinite is undefined.");
             }
 
-            
+            if ($b->isInteger()) {
+                if (preg_match('/^[+\-]?[0-9]*[02468](\.0+)?$/', $b->value, $captures) === 1) {
+                    // $b is an even number
+                    return self::$pInf;
+                } else {
+                    // $b is an odd number
+                    return $this; // self::$nInf;
+                }
+            }
 
             throw new NotImplementedException("See issues #21, #22, #23 and #24 on Github.");
 
         } else if ($b->isNegative()) {
             return DecimalConstants::Zero();
+        } else if ($b->isZero()) {
+            throw new \DomainException("Infinite elevated to zero is undefined.");
         }
     }
 

tests/Decimal/DecimalTanTest.php

@@ -29,19 +29,14 @@ public function testSimple($nr, $answer, $digits)
             'tan('.$nr.') must be equal to '.$answer.', but was '.$tanX
         );
     }
-    
-    public function testTanPiTwoDiv()
-    {    	
-        $PI  = DecimalConstants::PI();
-        $two = Decimal::fromInteger(2);
-        $PiDividedByTwo = $PI->div($two);
 
-        $catched = false;
-        try {
-            $PiDividedByTwo->tan();
-        } catch (\DomainException $e) {
-            $catched = true;
-        }
-        $this->assertTrue($catched);
+    /**
+     * @expectedException \DomainException
+     * @expectedExceptionMessage The tangent of this 'angle' is undefined.
+     */
+    public function testTanPiTwoDiv()
+    {
+        $PiDividedByTwo = DecimalConstants::PI()->div(Decimal::fromInteger(2));
+        $PiDividedByTwo->tan();
     }
 }

tests/InfiniteDecimal/InfiniteDecimalPowTest.php

@@ -62,13 +62,21 @@ public function testNegativeInfiniteNegativePower()
         $this->assertTrue($nInf->pow($nInf)->equals($zero));
     }
 
+    /**
+     * @expectedException \DomainException
+     * @expectedExceptionMessage Infinite elevated to zero is undefined.
+     */
     public function testPositiveInfiniteZeroPower()
     {
-        $this->assertTrue(false);
+        InfiniteDecimal::getPositiveInfinite()->pow(DecimalConstants::Zero());
     }
 
+    /**
+     * @expectedException \DomainException
+     * @expectedExceptionMessage Infinite elevated to zero is undefined.
+     */
     public function testNegativeInfiniteZeroPower()
     {
-        $this->assertTrue(false);
+        InfiniteDecimal::getNegativeInfinite()->pow(DecimalConstants::Zero());
     }
 }