Parser: Plus and Minus with numbers.

VAR.ExpressionEvaluator.Tests/ParserTests.cs

@@ -0,0 +1,40 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace VAR.ExpressionEvaluator.Tests
+{
+    [TestClass()]
+    public class ParserTests
+    {
+        [TestMethod()]
+        public void ParseString__Ten_EqualsTen()
+        {
+            string expression = "10";
+            object result = Parser.EvaluateString(expression);
+            Assert.AreEqual(10m, result);
+        }
+
+        [TestMethod()]
+        public void ParseString__OnePlusTwo_EqualsThree()
+        {
+            string expression = "1   + 2";
+            object result = Parser.EvaluateString(expression);
+            Assert.AreEqual(3m, result);
+        }
+
+        [TestMethod()]
+        public void ParseString__OneMinusTwo_EqualsMinusOne()
+        {
+            string expression = "1   - 2";
+            object result = Parser.EvaluateString(expression);
+            Assert.AreEqual(-1m, result);
+        }
+
+        [TestMethod()]
+        public void ParseString__OneMillionMinusHundredThousands_EqualsNineHundredThousands()
+        {
+            string expression = "1000000   - 100000";
+            object result = Parser.EvaluateString(expression);
+            Assert.AreEqual(900000m, result);
+        }
+    }
+}

VAR.ExpressionEvaluator.Tests/VAR.ExpressionEvaluator.Tests.csproj

@@ -54,6 +54,7 @@
     <Compile Include="ExpressionBinaryNodeTests.cs" />
     <Compile Include="ExpressionNumberNodeTests.cs" />
     <Compile Include="ExpressionStringNodeTests.cs" />
+    <Compile Include="ParserTests.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="TokenizerTests.cs" />
   </ItemGroup>