Support for better invalid expression detection and divide by zero (#30)

* Additional validation for bad expressions (*+ for example)

* Removing DivisionByZeroException testing for now

Added more unit tests.

1 files changed, 39 insertions, 3 deletions

diff --git a/tests/MathTest.php b/tests/MathTest.php
index db6e486..c8b8a03 100644
--- a/tests/MathTest.php
+++ b/tests/MathTest.php
@@ -11,7 +11,15 @@
 
 namespace NXP\Tests;
 
-use \NXP\MathExecutor;
+use NXP\MathExecutor;
+use NXP\Exception\DivisionByZeroException;
+use NXP\Exception\IncorrectBracketsException;
+use NXP\Exception\IncorrectExpressionException;
+use NXP\Exception\MathExecutorException;
+use NXP\Exception\UnknownFunctionException;
+use NXP\Exception\UnknownOperatorException;
+use NXP\Exception\UnknownTokenException;
+use NXP\Exception\UnknownVariableException;
 
 class MathTest extends \PHPUnit_Framework_TestCase
 {
@@ -27,10 +35,28 @@ class MathTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals($calculator->execute($expression), $phpResult);
     }
 
+    public function testUnknownFunctionException()
+    {
+        $calculator = new MathExecutor();
+        $this->expectException(UnknownFunctionException::class);
+        $calculator->execute('1 * fred("wilma") + 3');
+    }
+
+    public function testIncorrectExpressionException()
+    {
+        $calculator = new MathExecutor();
+        $this->expectException(IncorrectExpressionException::class);
+        $calculator->execute('1 * + ');
+    }
+
     public function testZeroDivision()
     {
         $calculator = new MathExecutor();
         $this->assertEquals($calculator->execute('1 / 0'), 0);
+
+        // future version with allow for optional exceptions on divide by zero
+        // $this->expectException(DivisionByZeroException::class);
+        // $calculator->execute('1 / 0');
     }
 
     public function testExponentiation()
@@ -63,15 +89,25 @@ class MathTest extends \PHPUnit_Framework_TestCase
 
             ['(5 + 3) * -1'],
 
-            ['2+2*2'],
+            ['2- 2*2'],
+            ['2-(2*2)'],
+            ['(2- 2)*2'],
+            ['2 + 2*2'],
+            ['2+ 2*2'],
             ['(2+2)*2'],
-            ['(2+2)*-2'],
+            ['(2 + 2)*-2'],
             ['(2+-2)*2'],
 
             ['sin(10) * cos(50) / min(10, 20/2)'],
 
             ['100500 * 3.5E5'],
             ['100500 * 3.5E-5'],
+
+            ['-1 + -2'],
+            ['-1+-2'],
+            ['-1- -2'],
+            ['-1/-2'],
+            ['-1*-2'],
         ];
     }