Add ToStringTests

Test cases that covers the new behavior for using value/unit by default and
how the ToString() overloads with additional parameters affect the output.
Some of these tests probably overlap with existing tests in UnitSystemTests, but
will address that when moving those tests here.

Author: angularsen

UnitsNet.Tests/ToStringTests.cs

@@ -0,0 +1,105 @@
+// Copyright (c) 2013 Andreas Gullberg Larsen (andreas.larsen84@gmail.com).
+// https://github.com/angularsen/UnitsNet
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System.Globalization;
+using UnitsNet.Units;
+using Xunit;
+
+namespace UnitsNet.Tests
+{
+    public class ToStringTests
+    {
+        [Fact]
+        public void ReturnsTheOriginalValueAndUnit()
+        {
+            var oldCulture = UnitSystem.DefaultCulture;
+            try
+            {
+                UnitSystem.DefaultCulture = CultureInfo.InvariantCulture;
+                Assert.Equal("5 kg", Mass.FromKilograms(5).ToString());
+                Assert.Equal("5,000 g", Mass.FromGrams(5000).ToString());
+                Assert.Equal("1e-04 long tn", Mass.FromLongTons(1e-4).ToString());
+                Assert.Equal("3.46e-04 dN/m", ForcePerLength.FromDecinewtonsPerMeter(0.00034567).ToString());
+                Assert.Equal("0.0069 dB", Level.FromDecibels(0.0069).ToString());
+                Assert.Equal("0.011 kWh/kg", SpecificEnergy.FromKilowattHoursPerKilogram(0.011).ToString());
+//                Assert.Equal("0.1 MJ/kg·C", SpecificEntropy.FromMegajoulesPerKilogramDegreeCelsius(0.1).ToString());
+                Assert.Equal("0.1 MJ/kg.C", SpecificEntropy.FromMegajoulesPerKilogramDegreeCelsius(0.1).ToString());
+                Assert.Equal("5 cm", Length.FromCentimeters(5).ToString());
+            }
+            finally
+            {
+                UnitSystem.DefaultCulture = oldCulture;
+            }
+        }
+
+        [Fact]
+        public void ConvertsToTheGivenUnit()
+        {
+            var oldCulture = UnitSystem.DefaultCulture;
+            try
+            {
+                UnitSystem.DefaultCulture = CultureInfo.InvariantCulture;
+                Assert.Equal("5,000 g", Mass.FromKilograms(5).ToString(MassUnit.Gram));
+                Assert.Equal("5 kg", Mass.FromGrams(5000).ToString(MassUnit.Kilogram));
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToString(LengthUnit.Meter));
+                Assert.Equal("1.97 in", Length.FromCentimeters(5).ToString(LengthUnit.Inch));
+            }
+            finally
+            {
+                UnitSystem.DefaultCulture = oldCulture;
+            }
+        }
+
+        [Fact]
+        public void FormatsNumberUsingGivenCulture()
+        {
+            var oldCulture = UnitSystem.DefaultCulture;
+            try
+            {
+                UnitSystem.DefaultCulture = CultureInfo.InvariantCulture;
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToString(LengthUnit.Meter, null));
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToString(LengthUnit.Meter, CultureInfo.InvariantCulture));
+                Assert.Equal("0,05 m", Length.FromCentimeters(5).ToString(LengthUnit.Meter, new CultureInfo("nb-NO")));
+            }
+            finally
+            {
+                UnitSystem.DefaultCulture = oldCulture;
+            }
+        }
+
+        [Fact]
+        public void FormatsNumberUsingGivenDigitsAfterRadix()
+        {
+            var oldCulture = UnitSystem.DefaultCulture;
+            try
+            {
+                UnitSystem.DefaultCulture = CultureInfo.InvariantCulture;
+                Assert.Equal("0.05 m", Length.FromCentimeters(5).ToString(LengthUnit.Meter, null, 4));
+                Assert.Equal("1.97 in", Length.FromCentimeters(5).ToString(LengthUnit.Inch, null, 2));
+                Assert.Equal("1.9685 in", Length.FromCentimeters(5).ToString(LengthUnit.Inch, null, 4));
+            }
+            finally
+            {
+                UnitSystem.DefaultCulture = oldCulture;
+            }
+        }
+    }
+}