add unit test and format

Author: Poker-sang

src/ImageSharp/Formats/Webp/BitWriter/Vp8LBitWriter.cs

@@ -44,9 +44,6 @@ public Vp8LBitWriter(int expectedSize)
     {
     }
 
-    /// <inheritdoc/>
-    public override int NumBytes => this.cur + ((this.used + 7) >> 3);
-
     /// <summary>
     /// Initializes a new instance of the <see cref="Vp8LBitWriter"/> class.
     /// Used internally for cloning.
@@ -59,6 +56,9 @@ private Vp8LBitWriter(byte[] buffer, ulong bits, int used, int cur)
         this.cur = cur;
     }
 
+    /// <inheritdoc/>
+    public override int NumBytes => this.cur + ((this.used + 7) >> 3);
+
     /// <summary>
     /// This function writes bits into bytes in increasing addresses (little endian),
     /// and within a byte least-significant-bit first. This function can write up to 32 bits in one go.

tests/ImageSharp.Tests/Formats/WebP/WebpEncoderTests.cs

@@ -2,6 +2,7 @@
 // Licensed under the Six Labors Split License.
 
 using System.Runtime.InteropServices;
+using SixLabors.ImageSharp.Formats.Png;
 using SixLabors.ImageSharp.Formats.Webp;
 using SixLabors.ImageSharp.Metadata;
 using SixLabors.ImageSharp.PixelFormats;
@@ -17,14 +18,28 @@ public class WebpEncoderTests
 {
     private static string TestImageLossyFullPath => Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, Lossy.NoFilter06);
 
-    [Fact]
-    public void Encode_AnimatedLossy()
+    [Theory]
+    [WithFile(Lossless.Animated, PixelTypes.Rgba32)]
+    public void Encode_AnimatedLossless<TPixel>(TestImageProvider<TPixel> provider)
+        where TPixel : unmanaged, IPixel<TPixel>
     {
-        Image<Rgba32> image = Image.Load<Rgba32>(@"C:\WorkSpace\ImageSharp\tests\Images\Input\Webp\leo_animated_lossless.webp");
-        image.SaveAsWebp(@"C:\Users\poker\Desktop\3.webp", new WebpEncoder()
-        {
-            FileFormat = WebpFileFormatType.Lossless
-        });
+        using Image<TPixel> image = provider.GetImage();
+        using MemoryStream memStream = new();
+        image.SaveAsWebp(memStream, new() { FileFormat = WebpFileFormatType.Lossless });
+
+        // TODO: DebugSave, VerifySimilarity
+    }
+
+    [Theory]
+    [WithFile(Lossy.Animated, PixelTypes.Rgba32)]
+    public void Encode_AnimatedLossy<TPixel>(TestImageProvider<TPixel> provider)
+        where TPixel : unmanaged, IPixel<TPixel>
+    {
+        using Image<TPixel> image = provider.GetImage();
+        using MemoryStream memStream = new();
+        image.SaveAsWebp(memStream, new());
+
+        // TODO: DebugSave, VerifySimilarity
     }
 
     [Theory]