feat (Tests): adds tests for DefaultDropPictureTagHelperRenderer

tests/Rhythm.Drop.Web.Tests/TagHelperRenderers/Images/DefaultPictureTagHelperRendererTests.cs

@@ -0,0 +1,84 @@
+namespace Rhythm.Drop.Web.Tests.TagHelperRenderers.Images;
+
+using Rhythm.Drop.Web.Infrastructure.TagHelperRenderers.Images;
+using Rhythm.Drop.Web.Infrastructure;
+using Rhythm.Drop.Web.TagHelperRenderers.Images;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Rhythm.Drop.Models.Images;
+using Microsoft.AspNetCore.Html;
+
+[TestFixture]
+public class DefaultPictureTagHelperRendererTests : TagHelperRendererTestsBase
+{
+    private const string PictureTagName = "picture";
+
+    private static readonly IHtmlContent _imgHtmlContent = new HtmlString("<img class=\"test\" />");
+
+    [Test]
+    public async Task RenderAsync_With_No_Existing_Img_Tag_Should_Return_Output_With_Modified_Content()
+    {
+        // arrange
+        var tagHelperRenderer = new DefaultDropPictureTagHelperRenderer();
+        var image = new Image("/image.gif", "Test", 200, 200);
+        var rendererContext = new DropImageTagHelperRendererContext(image, LoadingMode.Default);
+        var context = CreateTagHelperContext(PictureTagName);
+        var output = CreateTagHelperOutput(PictureTagName);
+
+        await tagHelperRenderer.RenderAsync(rendererContext, context, output);
+
+        Assert.That(output.Content.IsModified, Is.True);
+    }
+
+    [Test]
+    public async Task RenderAsync_With_Existing_Img_Tag_Should_Return_Output_With_No_Modified_Content()
+    {
+        // arrange
+        var tagHelperRenderer = new DefaultDropPictureTagHelperRenderer();
+        var image = new Image("/image.gif", "Test", 200, 200);
+        var rendererContext = new DropImageTagHelperRendererContext(image, LoadingMode.Default);
+        var context = CreateTagHelperContext(PictureTagName);
+        var output = CreateTagHelperOutput(PictureTagName, _imgHtmlContent);
+
+        await tagHelperRenderer.RenderAsync(rendererContext, context, output);
+
+        Assert.That(output.Content.IsModified, Is.False);
+    }
+
+    [Test]
+    public async Task RenderAsync_With_Img_And_Source_Tag_Should_Return_Output_With_Modified_PreContent()
+    {
+        // arrange
+        var tagHelperRenderer = new DefaultDropPictureTagHelperRenderer();
+        var image = new Image("/image.gif", "Test", 200, 200, [ new ImageSource("/image2.gif")]);
+        var rendererContext = new DropImageTagHelperRendererContext(image, LoadingMode.Default);
+        var context = CreateTagHelperContext(PictureTagName);
+        var output = CreateTagHelperOutput(PictureTagName, _imgHtmlContent);
+
+        await tagHelperRenderer.RenderAsync(rendererContext, context, output);
+
+        Assert.That(output.PreContent.IsModified, Is.True);
+    }
+
+    [Test]
+    public async Task RenderAsync_With_No_Img_Should_Return_Surpressed_Output()
+    {
+        // arrange
+        var tagHelperRenderer = new DefaultDropPictureTagHelperRenderer();
+        var rendererContext = new DropImageTagHelperRendererContext(default, LoadingMode.Default);
+        var context = CreateTagHelperContext(PictureTagName);
+        var output = CreateTagHelperOutput(PictureTagName, _imgHtmlContent);
+
+        await tagHelperRenderer.RenderAsync(rendererContext, context, output);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(output.TagName, Is.Default);
+            Assert.That(output.PreContent.IsEmptyOrWhiteSpace, Is.True);
+            Assert.That(output.Content.IsEmptyOrWhiteSpace, Is.True);
+        });
+    }
+}