[Gtk] Add TextIndexer tests

Testing/GtkTestRunner.csproj

@@ -111,6 +111,7 @@
     <Compile Include="Tests\DialogTests.cs" />
     <Compile Include="Tests\ScrollableWidgetTests.cs" />
     <Compile Include="GtkTestRunner\GtkInit.cs" />
+    <Compile Include="GtkTests\PangoTests.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <ItemGroup>

Testing/GtkTests/PangoTests.cs

@@ -0,0 +1,87 @@
+//
+// PangoTests.cs
+//
+// Author:
+//       Vsevolod Kukol <sevoku@microsoft.com>
+//
+// Copyright (c) 2017 (c) Microsoft Corporation
+//
+// 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 NUnit.Framework;
+using Xwt.GtkBackend;
+
+namespace Xwt
+{
+	[TestFixture]
+	public class PangoUtilTests
+	{
+		[Test]
+		public void TextIndexerAscii()
+		{
+			var str = "Test";
+			var indexer = new TextIndexer(str);
+
+			Assert.AreEqual(0, indexer.IndexToByteIndex(0));
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(0));
+			Assert.AreEqual(1, indexer.IndexToByteIndex(1));
+			Assert.AreEqual(1, indexer.ByteIndexToIndex(1));
+			Assert.AreEqual(2, indexer.IndexToByteIndex(2));
+			Assert.AreEqual(2, indexer.ByteIndexToIndex(2));
+			Assert.AreEqual(3, indexer.IndexToByteIndex(3));
+			Assert.AreEqual(3, indexer.ByteIndexToIndex(3));
+		}
+
+		[Test]
+		public void TextIndexerUnicode()
+		{
+			var str = "バージョン";
+			var indexer = new TextIndexer(str);
+
+			Assert.AreEqual(0, indexer.IndexToByteIndex(0));
+			Assert.AreEqual(3, indexer.IndexToByteIndex(1));
+			Assert.AreEqual(6, indexer.IndexToByteIndex(2));
+
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(0));
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(1));
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(2));
+			Assert.AreEqual(1, indexer.ByteIndexToIndex(3));
+			Assert.AreEqual(1, indexer.ByteIndexToIndex(4));
+			Assert.AreEqual(1, indexer.ByteIndexToIndex(5));
+		}
+
+		[Test]
+		public void TextIndexerMixed()
+		{
+			var str = "バAジョン";
+			var indexer = new TextIndexer(str);
+
+			Assert.AreEqual(0, indexer.IndexToByteIndex(0));
+			Assert.AreEqual(3, indexer.IndexToByteIndex(1));
+			Assert.AreEqual(4, indexer.IndexToByteIndex(2));
+
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(0));
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(1));
+			Assert.AreEqual(0, indexer.ByteIndexToIndex(2));
+			Assert.AreEqual(1, indexer.ByteIndexToIndex(3));
+			Assert.AreEqual(2, indexer.ByteIndexToIndex(4));
+			Assert.AreEqual(2, indexer.ByteIndexToIndex(5));
+		}
+	}
+}
+

Xwt.Gtk/Xwt.GtkBackend/GtkInterop.cs

@@ -228,7 +228,7 @@ namespace Xwt.GtkBackend
 		}
 	}
 
-	internal class TextIndexer
+	public class TextIndexer
 	{
 		static readonly List<int> emptyList = new List<int> ();
 		static readonly int [] emptyArray = new int [0];