1 files changed, 10 insertions, 0 deletions
diff --git a/tests/MathTest.php b/tests/MathTest.php
index 0de2465..cc4cd1a 100644
--- a/tests/MathTest.php
+++ b/tests/MathTest.php
@@ -37,6 +37,10 @@ class MathTest extends \PHPUnit\Framework\TestCase
 
     /**
      * Expressions data provider
+	 *
+	 * Most tests can go in here.  The idea is that each expression will be evaluated by MathExecutor and by PHP with eval.
+	 * The results should be the same.  If they are not, then the test fails.  No need to add extra test unless you are doing
+	 * something more complete and not a simple mathmatical expression.
      */
     public function providerExpressions()
     {
@@ -186,6 +190,12 @@ class MathTest extends \PHPUnit\Framework\TestCase
             ['1 + 5 < 3 + 1'],
             ['1 + 3 <= 5 + 1'],
             ['1 + 5 <= 5 + 1'],
+
+            ['(-4)'],
+            ['(-4 + 5)'],
+
+            ['1 - 0'],
+            ['1-0'],
         ];
     }