Fix CurrentUrlPath being empty on deeply nested snippets

src/Elastic.Markdown/IO/DocumentationSet.cs

@@ -213,12 +213,10 @@ void ValidateExists(string from, string to, IReadOnlyDictionary<string, string?>
 
 	public FrozenDictionary<int, MarkdownFile> MarkdownFiles { get; }
 
-	public MarkdownFile? DocumentationFileLookup(IFileInfo sourceFile)
+	public DocumentationFile? DocumentationFileLookup(IFileInfo sourceFile)
 	{
 		var relativePath = Path.GetRelativePath(SourceDirectory.FullName, sourceFile.FullName);
-		if (FlatMappedFiles.TryGetValue(relativePath, out var file) && file is MarkdownFile markdownFile)
-			return markdownFile;
-		return null;
+		return FlatMappedFiles.GetValueOrDefault(relativePath);
 	}
 
 	public MarkdownFile? GetPrevious(MarkdownFile current)

src/Elastic.Markdown/IO/MarkdownFile.cs

@@ -41,6 +41,8 @@ DocumentationSet set
 	{
 		FileName = sourceFile.Name;
 		FilePath = sourceFile.FullName;
+		IsIndex = FileName == "index.md";
+
 		UrlPathPrefix = build.UrlPathPrefix;
 		MarkdownParser = parser;
 		Collector = build.Collector;
@@ -76,6 +78,8 @@ public DocumentationGroup? Parent
 	public YamlFrontMatter? YamlFrontMatter { get; private set; }
 	public string? TitleRaw { get; protected set; }
 
+	public bool IsIndex { get; internal set; }
+
 	public string? Title
 	{
 		get => _title;

src/Elastic.Markdown/IO/Navigation/DocumentationGroup.cs

@@ -315,6 +315,9 @@ .. documentationFiles
 			}
 		}
 
+		if (indexFile is not null)
+			indexFile.IsIndex = true;
+
 		return indexFile ?? files.FirstOrDefault();
 	}
 

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

@@ -227,8 +227,10 @@ private static void WriteIncludeBlock(HtmlRenderer renderer, IncludeBlock block,
 			return;
 
 		var snippet = block.Build.ReadFileSystem.FileInfo.New(block.IncludePath);
-		var parentPath = block.Context.MarkdownSourcePath;
+
+		var parentPath = block.Context.MarkdownParentPath ?? block.Context.MarkdownSourcePath;
 		var document = parser.ParseSnippetAsync(snippet, parentPath, block.Context.YamlFrontMatter, default).GetAwaiter().GetResult();
+
 		var html = document.ToHtml(parser.Pipeline);
 		_ = renderer.Write(html);
 	}

src/Elastic.Markdown/Myst/InlineParsers/DiagnosticLinkInlineParser.cs

@@ -289,11 +289,14 @@ private static IFileInfo ResolveFile(ParserContext context, string url) =>
 	private static void ValidateAnchor(InlineProcessor processor, MarkdownFile markdown, string anchor, LinkInline link)
 	{
 		if (!markdown.Anchors.Contains(anchor))
-			processor.EmitError(link, $"`{anchor}` does not exist in {markdown.FileName}.");
+			processor.EmitError(link, $"`{anchor}` does not exist in {markdown.RelativePath}.");
 	}
 
 	private static void UpdateLinkUrl(LinkInline link, string url, ParserContext context, string? anchor)
 	{
+		// TODO revisit when we refactor our documentation set graph
+		// This method grew too complex, we need to revisit our documentation set graph generation so we can ask these questions
+		// on `DocumentationFile` that are mostly precomputed
 		var urlPathPrefix = context.Build.UrlPathPrefix ?? string.Empty;
 
 		if (!url.StartsWith('/') && !string.IsNullOrEmpty(url))
@@ -303,16 +306,19 @@ private static void UpdateLinkUrl(LinkInline link, string url, ParserContext con
 				? context.CurrentUrlPath[urlPathPrefix.Length..]
 				: urlPathPrefix;
 
-			var markdownPath = context.MarkdownSourcePath.Name;
+			// if we are trying to resolve a relative url from a _snippet folder ensure we eat the _snippet folder
+			// as it's not part of url by chopping of the extra parent navigation
+			if (url.StartsWith("../") && context.DocumentationFileLookup(context.MarkdownSourcePath) is SnippetFile snippetFile)
+				url = url.Substring(3);
 
+			// TODO check through context.DocumentationFileLookup if file is index vs "index.md" check
+			var markdownPath = context.MarkdownSourcePath;
 			// if the current path is an index e.g /reference/cloud-k8s/
 			// './' current path lookups should be relative to sub-path.
 			// If it's not e.g /reference/cloud-k8s/api-docs/ these links should resolve on folder up.
-			var siblingsGoToCurrent = url.StartsWith("./") && markdownPath == "index.md";
 			var lastIndexPath = subPrefix.LastIndexOf('/');
-			if (lastIndexPath >= 0 && !siblingsGoToCurrent)
+			if (lastIndexPath >= 0 && markdownPath.Name != "index.md")
 				subPrefix = subPrefix[..lastIndexPath];
-
 			var combined = '/' + Path.Combine(subPrefix, url).TrimStart('/');
 			url = Path.GetFullPath(combined);
 		}
@@ -341,6 +347,7 @@ private static void UpdateLinkUrl(LinkInline link, string url, ParserContext con
 			url = url[..^5];
 
 		link.Url = string.IsNullOrEmpty(anchor) ? url : $"{url}#{anchor}";
+
 	}
 
 	private static bool IsCrossLink([NotNullWhen(true)] Uri? uri) =>

src/Elastic.Markdown/Myst/ParserContext.cs

@@ -53,6 +53,7 @@ public class ParserContext : MarkdownParserContext, IParserResolvers
 	public ConfigurationFile Configuration { get; }
 	public ICrossLinkResolver CrossLinkResolver { get; }
 	public IFileInfo MarkdownSourcePath { get; }
+	public IFileInfo? MarkdownParentPath { get; }
 	public string CurrentUrlPath { get; }
 	public YamlFrontMatter? YamlFrontMatter { get; }
 	public BuildContext Build { get; }
@@ -67,15 +68,16 @@ public ParserContext(ParserState state)
 		Configuration = state.Configuration;
 		YamlFrontMatter = state.YamlFrontMatter;
 		SkipValidation = state.SkipValidation;
+		MarkdownParentPath = state.ParentMarkdownPath;
 
 		CrossLinkResolver = state.CrossLinkResolver;
 		MarkdownSourcePath = state.MarkdownSourcePath;
 		DocumentationFileLookup = state.DocumentationFileLookup;
-		var parentPath = state.ParentMarkdownPath;
 
-		CurrentUrlPath = DocumentationFileLookup(parentPath ?? MarkdownSourcePath) is MarkdownFile md
+		CurrentUrlPath = DocumentationFileLookup(state.ParentMarkdownPath ?? MarkdownSourcePath) is MarkdownFile md
 			? md.Url
 			: string.Empty;
+
 		if (SkipValidation && string.IsNullOrEmpty(CurrentUrlPath))
 		{
 			//TODO investigate this deeper.

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

@@ -70,7 +70,7 @@ protected DirectiveTest(ITestOutputHelper output, [LanguageInjection("markdown")
 		var context = new BuildContext(Collector, FileSystem);
 		var linkResolver = new TestCrossLinkResolver();
 		Set = new DocumentationSet(context, logger, linkResolver);
-		File = Set.DocumentationFileLookup(FileSystem.FileInfo.New("docs/index.md")) ?? throw new NullReferenceException();
+		File = Set.DocumentationFileLookup(FileSystem.FileInfo.New("docs/index.md")) as MarkdownFile ?? throw new NullReferenceException();
 		Html = default!; //assigned later
 		Document = default!;
 	}

tests/Elastic.Markdown.Tests/Inline/InlneBaseTests.cs

@@ -117,7 +117,7 @@ protected InlineTest(
 		};
 		var linkResolver = new TestCrossLinkResolver();
 		Set = new DocumentationSet(context, logger, linkResolver);
-		File = Set.DocumentationFileLookup(FileSystem.FileInfo.New("docs/index.md")) ?? throw new NullReferenceException();
+		File = Set.DocumentationFileLookup(FileSystem.FileInfo.New("docs/index.md")) as MarkdownFile ?? throw new NullReferenceException();
 		Html = default!; //assigned later
 		Document = default!;
 	}