Add Markdown support to the CSV directive

docs/_snippets/sample-data-markdown.csv

@@ -0,0 +1,6 @@
+Name,Notes,Links
+Alpha,"**Bold** text, _italic_ text, and `code`.","[Google](https://www.google.com)"
+Bravo,"Inline role: {kbd}`Ctrl+C`.","[Elastic docs](https://www.elastic.co/docs)"
+Charlie,"Mixed **bold** and _italic_, plus `inline code`.","[Search](https://www.elastic.co/docs/solutions/search)"
+Delta,"Feature {applies_to}`stack: ga 9.1` available now.","[Elastic](https://www.elastic.co)"
+Echo,"This is {preview}`9.1` functionality.","[Preview docs](https://www.elastic.co/docs)"

docs/syntax/csv-include.md

@@ -57,6 +57,34 @@ The directive includes built-in performance limits to handle large files efficie
 - **Column limit**: Maximum of 10 columns will be displayed  
 - **File size limit**: Maximum file size of 10MB
 
+### Markdown rendering in cells
+
+Cells are parsed as Markdown, so they can render inline formatting and links. For example, a cell containing `**Bold**` becomes bold text, and `[Text](https://www.google.com)` becomes a link.
+
+Here is a complete example that uses multiple Markdown formats:
+
+:::::{tab-set}
+
+::::{tab-item} Output
+
+:::{csv-include} ../_snippets/sample-data-markdown.csv
+:caption: Sample data with Markdown formatting
+:::
+
+::::
+
+::::{tab-item} Markdown
+
+```markdown
+:::{csv-include} _snippets/sample-data-markdown.csv
+:caption: Sample data with Markdown formatting
+:::
+```
+
+::::
+
+:::::
+
 ## Performance considerations
 
 The CSV directive is optimized for large files:

src/Elastic.Markdown/Myst/Directives/CsvInclude/CsvIncludeBlock.cs

@@ -2,6 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using System.IO.Abstractions;
 using Elastic.Markdown.Diagnostics;
 
 namespace Elastic.Markdown.Myst.Directives.CsvInclude;
@@ -10,6 +11,10 @@ public class CsvIncludeBlock(DirectiveBlockParser parser, ParserContext context)
 {
 	public override string Directive => "csv-include";
 
+	public ParserContext Context { get; } = context;
+
+	public IFileInfo IncludeFrom { get; } = context.MarkdownSourcePath;
+
 	public string? CsvFilePath { get; private set; }
 	public string? CsvFilePathRelativeToSource { get; private set; }
 	public bool Found { get; private set; }

src/Elastic.Markdown/Myst/Directives/CsvInclude/CsvIncludeView.cshtml

@@ -26,7 +26,7 @@
             <tr>
                 @for (var i = 0; i < csvRows[0].Length; i++)
                 {
-                    <th>@csvRows[0][i]</th>
+                    <th>@Model.RenderCell(csvRows[0][i])</th>
                 }
             </tr>
         </thead>
@@ -37,7 +37,7 @@
                 <tr>
                     @for (var i = 0; i < csvRows[rowIndex].Length; i++)
                     {
-                        <td>@csvRows[rowIndex][i]</td>
+                        <td>@Model.RenderCell(csvRows[rowIndex][i])</td>
                     }
                 </tr>
             }

src/Elastic.Markdown/Myst/Directives/CsvInclude/CsvIncludeViewModel.cs

@@ -3,11 +3,14 @@
 // See the LICENSE file in the project root for more information
 
 using Elastic.Markdown.Diagnostics;
+using Microsoft.AspNetCore.Html;
 
 namespace Elastic.Markdown.Myst.Directives.CsvInclude;
 
 public class CsvIncludeViewModel : DirectiveViewModel
 {
+	public required Func<string, HtmlString> RenderMarkdown { get; init; }
+
 	public IEnumerable<string[]> GetCsvRows()
 	{
 		if (DirectiveBlock is not CsvIncludeBlock csvBlock || !csvBlock.Found || string.IsNullOrEmpty(csvBlock.CsvFilePath))
@@ -48,9 +51,18 @@ public IEnumerable<string[]> GetCsvRows()
 		});
 	}
 
-	public static CsvIncludeViewModel Create(CsvIncludeBlock csvBlock) =>
+	public HtmlString RenderCell(string? value)
+	{
+		if (string.IsNullOrEmpty(value))
+			return HtmlString.Empty;
+
+		return RenderMarkdown(value);
+	}
+
+	public static CsvIncludeViewModel Create(CsvIncludeBlock csvBlock, Func<string, HtmlString> renderMarkdown) =>
 		new()
 		{
-			DirectiveBlock = csvBlock
+			DirectiveBlock = csvBlock,
+			RenderMarkdown = renderMarkdown
 		};
 }

src/Elastic.Markdown/Myst/Directives/DirectiveHtmlRenderer.cs

@@ -2,6 +2,7 @@
 // Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
 // See the LICENSE file in the project root for more information
 
+using System;
 using System.Diagnostics.CodeAnalysis;
 using Elastic.Documentation.AppliesTo;
 using Elastic.Markdown.Diagnostics;
@@ -29,6 +30,7 @@
 using Markdig.Renderers.Html;
 using Markdig.Syntax;
 using Markdig.Syntax.Inlines;
+using Microsoft.AspNetCore.Html;
 using RazorSlices;
 using YamlDotNet.Core;
 
@@ -517,11 +519,45 @@ void Render(Block o)
 
 	private static void WriteCsvIncludeBlock(HtmlRenderer renderer, CsvIncludeBlock block)
 	{
-		var viewModel = CsvIncludeViewModel.Create(block);
+		var viewModel = CsvIncludeViewModel.Create(block, value => RenderCsvCellMarkdown(block, value));
 		var slice = CsvIncludeView.Create(viewModel);
 		RenderRazorSlice(slice, renderer);
 	}
 
+	private static HtmlString RenderCsvCellMarkdown(CsvIncludeBlock block, string value)
+	{
+		if (string.IsNullOrWhiteSpace(value))
+			return HtmlString.Empty;
+
+		var document = MarkdownParser.ParseMarkdownStringAsync(
+			block.Build,
+			block.Context,
+			value,
+			block.IncludeFrom,
+			block.Context.YamlFrontMatter,
+			MarkdownParser.Pipeline);
+
+		if (document.Count == 1 && document.FirstOrDefault() is ParagraphBlock paragraph && paragraph.Inline != null)
+			return RenderInlineMarkdown(paragraph);
+
+		var html = document.ToHtml(MarkdownParser.Pipeline);
+		return new HtmlString(html.EnsureTrimmed());
+	}
+
+	private static HtmlString RenderInlineMarkdown(ParagraphBlock paragraph)
+	{
+		if (paragraph.Inline is null)
+			return HtmlString.Empty;
+
+		var subscription = DocumentationObjectPoolProvider.HtmlRendererPool.Get();
+		subscription.HtmlRenderer.WriteChildren(paragraph.Inline);
+
+		var result = subscription.RentedStringBuilder?.ToString();
+		DocumentationObjectPoolProvider.HtmlRendererPool.Return(subscription);
+
+		return result == null ? HtmlString.Empty : new HtmlString(result.EnsureTrimmed());
+	}
+
 	private static void WriteChangelogBlock(HtmlRenderer renderer, ChangelogBlock block)
 	{
 		if (!block.Found || block.BundlesFolderPath is null)

tests/Elastic.Markdown.Tests/Directives/CsvIncludeTests.cs

@@ -123,6 +123,21 @@ public void HandlesEscapedQuotes()
 	}
 }
 
+public class CsvIncludeRenderLinksTests(ITestOutputHelper output) : DirectiveTest(output,
+"""
+::::{csv-include} test-data.csv
+::::
+""")
+{
+	protected override void AddToFileSystem(MockFileSystem fileSystem) =>
+		fileSystem.AddFile("docs/test-data.csv", new MockFileData(
+@"Name,Link
+Search,[Text](https://www.google.com)"));
+
+	[Fact]
+	public void RendersMarkdownLinkAsLink() => Html.Should().Contain(">Text</a>");
+}
+
 public class CsvIncludeNotFoundTests(ITestOutputHelper output) : DirectiveTest<CsvIncludeBlock>(output,
 """
 :::{csv-include} missing-file.csv