fix: ignore headings quoted in {noformat} and {code} blocks

PanoramicData.IssueAssessment.Tests/Text/IssueTextTests.cs

@@ -161,4 +161,40 @@ public void HeadingLevel_MapsBothDialectsToOneScale(string? line, int expected)
 	{
 		IssueText.HeadingLevel(line).Should().Be(expected);
 	}
+
+	// Issue #9 (MS-26773): a sample ticket quoted in a literal block brought its own headings with it.
+	public static TheoryData<string, string> QuotedSamples => new()
+	{
+		{ "{noformat}", "{noformat}" },
+		{ "{code}", "{code}" },
+		{ "{code:none}", "{code}" }
+	};
+
+	private static string WithQuotedSample(string open, string close)
+		=> "h2. Summary\r\nAdds a sample.\r\n\r\nh2. Acceptance Criteria\r\n# MUST: the sample renders.\r\n\r\nh2. Notes\r\n"
+			+ open + "\r\nh2. Acceptance Criteria\r\n# MUST: quoted.\r\nh2. Rollback plan\r\nRestore the backup.\r\nh2. Owner\r\nOps.\r\n" + close + "\r\n";
+
+	[Theory]
+	[MemberData(nameof(QuotedSamples))]
+	public void CriteriaHeadings_IgnoresHeadingsInsideLiteralBlocks(string open, string close)
+		=> IssueText.CriteriaHeadings(WithQuotedSample(open, close)).Should().Equal("Acceptance Criteria");
+
+	[Theory]
+	[MemberData(nameof(QuotedSamples))]
+	public void SectionBody_IgnoresHeadingsInsideLiteralBlocks(string open, string close)
+		=> IssueText.SectionBody(WithQuotedSample(open, close), "rollback").Should().BeNull();
+
+	[Theory]
+	[MemberData(nameof(QuotedSamples))]
+	public void SectionBody_KeepsTheLiteralBlockTextUnchanged(string open, string close)
+		=> IssueText.SectionBody(WithQuotedSample(open, close), "notes").Should().Contain("h2. Rollback plan\r\nRestore the backup.");
+
+	[Theory]
+	[MemberData(nameof(QuotedSamples))]
+	public void PanelLayoutOf_IgnoresHeadingsInsideLiteralBlocks(string open, string close)
+	{
+		var layout = IssueText.PanelLayoutOf(WithQuotedSample(open, close));
+
+		layout.Unpanelled.Concat(layout.Panelable).Should().NotContain("Rollback plan");
+	}
 }

PanoramicData.IssueAssessment/Text/IssueText.LiteralBlocks.cs

@@ -0,0 +1,67 @@
+using System.Text.RegularExpressions;
+
+namespace PanoramicData.IssueAssessment.Text;
+
+/// <summary>
+/// Keeps text quoted in <c>{noformat}</c> and <c>{code}</c> blocks from being read as the ticket's own structure.
+/// </summary>
+public static partial class IssueText
+{
+	/// <summary>
+	/// Blanks the first visible character of every line inside a literal block, so headings, list items and table rows
+	/// quoted there are not parsed. Length and positions are unchanged, so indexes still map onto the original text.
+	/// </summary>
+	private static string MaskLiteralBlocks(string text)
+	{
+		if (!LiteralBlockToken.IsMatch(text))
+		{
+			return text;
+		}
+
+		char[] masked = text.ToCharArray();
+		string? openKind = null;
+		int lineStart = 0;
+		while (lineStart < text.Length)
+		{
+			int lineEnd = text.IndexOf('\n', lineStart);
+			if (lineEnd < 0)
+			{
+				lineEnd = text.Length;
+			}
+
+			string line = text[lineStart..lineEnd];
+			int firstVisible = line.Length - line.TrimStart().Length;
+			if (openKind is not null && firstVisible < line.Length && line[firstVisible] != '{')
+			{
+				masked[lineStart + firstVisible] = ' ';
+			}
+
+			openKind = LiteralStateAfter(line, openKind);
+			lineStart = lineEnd + 1;
+		}
+
+		return new string(masked);
+	}
+
+	/// <summary>
+	/// The open block kind after <paramref name="line"/>: <c>{noformat}</c> closes only <c>{noformat}</c>, and inside
+	/// a <c>{code}</c> block only <c>{code}</c> closes it.
+	/// </summary>
+	private static string? LiteralStateAfter(string line, string? openKind)
+	{
+		foreach (Match token in LiteralBlockToken.Matches(line))
+		{
+			string kind = token.Groups[1].Value.ToLowerInvariant();
+			if (openKind is null)
+			{
+				openKind = kind;
+			}
+			else if (openKind == kind && !token.Value.Contains(':', StringComparison.Ordinal))
+			{
+				openKind = null;
+			}
+		}
+
+		return openKind;
+	}
+}

PanoramicData.IssueAssessment/Text/IssueText.Panels.cs

@@ -24,6 +24,7 @@ public static PanelLayout PanelLayoutOf(string? text)
 			return PanelLayout.Empty;
 		}
 
+		text = MaskLiteralBlocks(text);
 		List<string> panelable = [];
 		List<string> unpanelled = [];
 		List<string> titled = [];

PanoramicData.IssueAssessment/Text/IssueText.Patterns.cs

@@ -35,6 +35,7 @@ public static partial class IssueText
 	private static readonly Regex PanelSectionHeading = new(@"^[ \t]*h([12])\.(.*)$", Options, Timeout);
 	private static readonly Regex PanelOpening = new(@"^[ \t]*\{panel(?::([^}]*))?\}", Options | RegexOptions.IgnoreCase, Timeout);
 	private static readonly Regex PanelBlocker = new(@"^[ \t]*\||\{(?:code|noformat)\b", Options | RegexOptions.IgnoreCase, Timeout);
+	private static readonly Regex LiteralBlockToken = new(@"\{(noformat|code)(?::[^}\r\n]*)?\}", Options | RegexOptions.IgnoreCase, Timeout);
 
 	private static readonly Regex PlaceholderListMarker = new(@"(?m)^[ \t]*(?:[-*#>]+|\d+\.)[ \t]*", Options, Timeout);
 	private static readonly Regex PlaceholderPunctuation = new(@"[\*_`{}\[\]\(\)\|:;,\.\-–—/\\]", Options, Timeout);

PanoramicData.IssueAssessment/Text/IssueText.cs

@@ -47,19 +47,22 @@ public static partial class IssueText
 		Regex heading = RegexCache.GetOrAdd(@"(?im)^[ \t]*(?:h[1-6]\.|#{1,6}[ \t]|\*{1,2}(?=[^\r\n]*\*{1,2}[ \t]*\r?$))[^\r\n]*" + headingKeywordPattern + @"[^\r\n]*");
 		Regex label = RegexCache.GetOrAdd(@"(?im)^[ \t]*(?![hH][1-6]\.)(?=[A-Za-z])[^\r\n:#*]{0,60}?" + headingKeywordPattern + @"[^\r\n:]{0,60}:[ \t]*\r?$");
 
-		IEnumerable<Match> openings = heading.Matches(text).Concat(label.Matches(text));
+		// Sections are found in the masked text; bodies are cut from the original, which has the same positions.
+		string scan = MaskLiteralBlocks(text);
+		IEnumerable<Match> openings = heading.Matches(scan).Concat(label.Matches(scan));
 
 		// In wiki text a "#" line is a list item, so it cannot open a section; only a "##"-or-deeper line that does not
 		// continue a "#" list may.
-		if (WikiHeadingAnywhere.IsMatch(text))
+		if (WikiHeadingAnywhere.IsMatch(scan))
 		{
-			openings = openings.Where(opening => IsWikiTextOpening(text, opening));
+			openings = openings.Where(opening => IsWikiTextOpening(scan, opening));
 		}
 
 		string? best = null;
 		foreach (Match opening in openings)
 		{
-			string body = SectionAfter(opening.Value, text[(opening.Index + opening.Length)..]);
+			int start = opening.Index + opening.Length;
+			string body = text.Substring(start, SectionAfter(opening.Value, scan[start..]).Length);
 			if (best is null || body.Length > best.Length)
 			{
 				best = body;
@@ -86,6 +89,7 @@ public static IReadOnlyList<string> CriteriaHeadings(string? text)
 			return [];
 		}
 
+		text = MaskLiteralBlocks(text);
 		string[] lines = LineBreak.Split(text);
 		List<(int Index, int Level, string Text)> headings = Headings(lines, WikiHeadingAnywhere.IsMatch(text));
 		List<string> found = [];