Fix negative numbers not supported by toString()

brick · Jun 7, 2015 · 2c35d6f · 2c35d6f
1 parent de917b9
commit 2c35d6f
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/src/BigInteger.php b/src/BigInteger.php
@@ -532,8 +532,6 @@ public function toInteger()
     }
 
     /**
-     * @todo test with negative numbers, probably broken
-     *
      * Returns a string representation of this number in the given base.
      *
      * @param integer $base
@@ -559,6 +557,12 @@ public function toString($base)
         $calc = Calculator::get();
 
         $value = $this->value;
+        $negative = ($value[0] === '-');
+
+        if ($negative) {
+            $value = substr($value, 1);
+        }
+
         $base = (string) $base;
         $result = '';
 
@@ -569,6 +573,10 @@ public function toString($base)
             $result .= $dictionary[$remainder];
         }
 
+        if ($negative) {
+            $result .= '-';
+        }
+
         return strrev($result);
     }
 

diff --git a/tests/BigIntegerTest.php b/tests/BigIntegerTest.php
@@ -1483,6 +1483,7 @@ public function testToIntegerPositiveOverflowThrowsException()
     public function testToString($number, $base, $expected)
     {
         $this->assertSame($expected, BigInteger::parse($number)->toString($base));
+        $this->assertSame('-' . $expected, BigInteger::parse('-' . $number)->toString($base));
     }
 
     /**