Minor code improvements

Author: onizet

src/Html2OpenXml/IO/ImageHeader.cs

@@ -114,8 +114,9 @@ public static Size KeepAspectRatio(Size actualSize, Size preferredSize)
     }
 
     /// <summary>
-    /// Examines the a file's first bytes and estimates the file's type.
+    /// Examines the first bytes of the file and estimates its image type if possible.
     /// </summary>
+    /// <returns>Returns <see cref="FileType.Unrecognized"/> if not recognized.</returns>
     private static FileType DetectFileType (SequentialBinaryReader reader)
     {
         byte[] magicBytes = new byte[MaxMagicBytesLength];

src/Html2OpenXml/Primitives/Size.cs

@@ -15,7 +15,7 @@ namespace HtmlToOpenXml;
 /// <summary>
 /// Represents a dimension in 2D coordinate space.
 /// </summary>
-public struct Size
+public struct Size : System.IEquatable<Size>
 {
     /// <summary>
     /// Initializes a new instance of the <see cref='HtmlToOpenXml.Size'/> class.
@@ -46,4 +46,18 @@ public Size(int width, int height)
     /// Represents the vertical component of this size.
     /// </summary>
     public int Height { get; set; }
+
+    /// <inheritdoc/>
+    public bool Equals(Size other)
+    {
+        return this.Width == other.Width && this.Height == other.Height;
+    }
+
+    /// <summary>
+    /// Gets a representation of this size.
+    /// </summary>
+    public override string ToString()
+    {
+        return string.Format("({0},{1})", Width, Height);
+    }
 }

test/HtmlToOpenXml.Tests/ImageFormats/ImageHeaderTests.cs

@@ -9,36 +9,25 @@ namespace HtmlToOpenXml.Tests.ImageFormats
     [TestFixture]
     public class ImageHeaderTests
     {
-        [TestCase("Resources.html2openxml.bmp")]
-        [TestCase("Resources.html2openxml.gif")]
-        [TestCase("Resources.html2openxml.jpg")]
-        [TestCase("Resources.html2openxml.png")]
-        [TestCase("Resources.html2openxml.emf")]
-        public void GuessFormat_ReturnsImageSize(string resourceName)
+        [TestCaseSource(nameof(GuessImageSizeTestCases))]
+        public void GuessFormat_ReturnsImageSize((string resourceName, Size expectedSize) td)
         {
-            using (var imageStream = ResourceHelper.GetStream(resourceName))
+            using (var imageStream = ResourceHelper.GetStream(td.resourceName))
             {
                 Size size = ImageHeader.GetDimensions(imageStream);
-                Assert.Multiple(() =>
-                {
-                    Assert.That(size.Width, Is.EqualTo(100));
-                    Assert.That(size.Height, Is.EqualTo(100));
-                });
+                Assert.That(size, Is.EqualTo(td.expectedSize));
             }
         }
 
-        [Test]
-        public void AnimatedGif_ReturnsImageSize()
+        private static IEnumerable<(string, Size)> GuessImageSizeTestCases()
         {
-            using (var imageStream = ResourceHelper.GetStream("Resources.stan.gif"))
-            {
-                Size size = ImageHeader.GetDimensions(imageStream);
-                Assert.Multiple(() =>
-                {
-                    Assert.That(size.Width, Is.EqualTo(252));
-                    Assert.That(size.Height, Is.EqualTo(318));
-                });
-            }
+            yield return ("Resources.html2openxml.bmp", new Size(100, 100));
+            yield return ("Resources.html2openxml.gif", new Size(100, 100));
+            yield return ("Resources.html2openxml.jpg", new Size(100, 100));
+            yield return ("Resources.html2openxml.png", new Size(100, 100));
+            yield return ("Resources.html2openxml.emf", new Size(100, 100));
+            // animated gif:
+            yield return ("Resources.stan.gif", new Size(252, 318));
         }
 
         /// <summary>

test/HtmlToOpenXml.Tests/Primitives/MarginTests.cs

@@ -51,5 +51,24 @@ public void ParseWithFloat_ShouldSucceed ()
                 Assert.That(Math.Round(margin.Left.ValueInPoint * 2).ToString(), Is.EqualTo("0"));
             });
         }
+
+        [Test]
+        public void ParseWithAuto_ShouldSucceed ()
+        {
+            var margin = Margin.Parse("0 auto");
+
+            Assert.Multiple(() => {
+                Assert.That(margin.IsValid, Is.EqualTo(true));
+
+                Assert.That(margin.Top.Value, Is.EqualTo(0));
+                Assert.That(margin.Top.Type, Is.EqualTo(UnitMetric.Pixel));
+
+                Assert.That(margin.Bottom.Value, Is.EqualTo(0));
+                Assert.That(margin.Bottom.Type, Is.EqualTo(UnitMetric.Pixel));
+
+                Assert.That(margin.Left.Type, Is.EqualTo(UnitMetric.Auto));
+                Assert.That(margin.Right.Type, Is.EqualTo(UnitMetric.Auto));
+            });
+        }
     }
 }