Added a SVG canvas test

tests/Tests/SKSvgTest.cs

@@ -1,6 +1,7 @@
 using System;
 using System.IO;
 using NUnit.Framework;
+using System.Xml.Linq;
 
 namespace SkiaSharp.Tests
 {
@@ -10,7 +11,7 @@ namespace SkiaSharp.Tests
 		[Test]
 		public void LoadSvgCanvasSize()
 		{
-			var path = Path.Combine (PathToImages, "logos.svg");
+			var path = Path.Combine(PathToImages, "logos.svg");
 
 			var svg = new SKSvg();
 			svg.Load(path);
@@ -21,7 +22,7 @@ namespace SkiaSharp.Tests
 		[Test]
 		public void LoadSvgCustomCanvasSize()
 		{
-			var path = Path.Combine (PathToImages, "logos.svg");
+			var path = Path.Combine(PathToImages, "logos.svg");
 
 			var svg = new SKSvg(new SKSize(150, 150));
 			svg.Load(path);
@@ -32,7 +33,7 @@ namespace SkiaSharp.Tests
 		[Test]
 		public void SvgLoadsToBitmap()
 		{
-			var path = Path.Combine (PathToImages, "logos.svg");
+			var path = Path.Combine(PathToImages, "logos.svg");
 			var background = (SKColor)0xfff8f8f8;
 
 			var svg = new SKSvg();
@@ -43,7 +44,55 @@ namespace SkiaSharp.Tests
 			canvas.DrawPicture(svg.Picture);
 			canvas.Flush();
 
-			Assert.AreEqual(background, bmp.GetPixel(0,0));
+			Assert.AreEqual(background, bmp.GetPixel(0, 0));
+		}
+
+		[Test]
+		public void SvgCanvasCreatesValidDrawing()
+		{
+			using (var stream = new MemoryStream())
+			{
+				// draw the SVG
+				using (var skStream = new SKManagedWStream(stream, false))
+				using (var writer = new SKXmlStreamWriter(skStream))
+				using (var canvas = SKSvgCanvas.Create(SKRect.Create(200, 150), writer))
+				{
+					var rectPaint = new SKPaint { Color = SKColors.Blue, Style = SKPaintStyle.Fill };
+					canvas.DrawRect(SKRect.Create(50, 70, 100, 30), rectPaint);
+
+					var circlePaint = new SKPaint { Color = SKColors.Red, Style = SKPaintStyle.Fill };
+					canvas.DrawOval(SKRect.Create(50, 70, 100, 30), circlePaint);
+
+					skStream.Flush();
+				}
+
+				// reset the sream
+				stream.Position = 0;
+
+				// read the SVG
+				var xdoc = XDocument.Load(stream);
+				var svg = xdoc.Root;
+
+				var ns = (XNamespace)"http://www.w3.org/2000/svg";
+
+				Assert.AreEqual(ns, svg.GetDefaultNamespace());
+				Assert.AreEqual("200", svg.Attribute("width").Value);
+				Assert.AreEqual("150", svg.Attribute("height").Value);
+
+				var rect = svg.Element(ns + "rect");
+				Assert.AreEqual("rgb(0,0,255)", rect.Attribute("fill").Value);
+				Assert.AreEqual("50", rect.Attribute("x").Value);
+				Assert.AreEqual("70", rect.Attribute("y").Value);
+				Assert.AreEqual("100", rect.Attribute("width").Value);
+				Assert.AreEqual("30", rect.Attribute("height").Value);
+
+				var ellipse = svg.Element(ns + "ellipse");
+				Assert.AreEqual("rgb(255,0,0)", ellipse.Attribute("fill").Value);
+				Assert.AreEqual("100", ellipse.Attribute("cx").Value);
+				Assert.AreEqual("85", ellipse.Attribute("cy").Value);
+				Assert.AreEqual("50", ellipse.Attribute("rx").Value);
+				Assert.AreEqual("15", ellipse.Attribute("ry").Value);
+			}
 		}
 	}
 }