From 5938024bc220d5238ce427aaad98366fb21fc9e2 Mon Sep 17 00:00:00 2001
From: Gordon Woodhull <gordon.woodhull@posit.co>
Date: Fri, 19 Dec 2025 18:39:42 -0500
Subject: [PATCH] bug fix: HR vs YAML block parsing in breakQuartoMd

---
 src/core/lib/break-quarto-md.ts               |  4 +--
 .../break-quarto-md/break-quarto-md.test.ts   | 35 +++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/src/core/lib/break-quarto-md.ts b/src/core/lib/break-quarto-md.ts
index dfe7ba3a02b..563f78cfa0f 100644
--- a/src/core/lib/break-quarto-md.ts
+++ b/src/core/lib/break-quarto-md.ts
@@ -168,11 +168,11 @@ export async function breakQuartoMd(
       return false;
     }
 
-    // if a yaml delimiter is surrounded by whitespace-only lines,
+    // if a yaml delimiter is followed by a whitespace-only line,
     // then it is actually an HR element; treat it as such.
+    // (YAML opening delimiters are followed by content like "key: value")
     if (
       skipHRs &&
-      index > 0 && srcLines[index - 1].substring.trim() === "" &&
       index < srcLines.length - 1 && srcLines[index + 1].substring.trim() === ""
     ) {
       return false;
diff --git a/tests/unit/break-quarto-md/break-quarto-md.test.ts b/tests/unit/break-quarto-md/break-quarto-md.test.ts
index 2e2a8ee1db3..21b9bdda24f 100644
--- a/tests/unit/break-quarto-md/break-quarto-md.test.ts
+++ b/tests/unit/break-quarto-md/break-quarto-md.test.ts
@@ -133,3 +133,38 @@ And what about this?
   const cells = (await breakQuartoMd(qmd, false)).cells;
   assert(cells.length <= 2 || cells[2].cell_type === "markdown");
 });
+
+unitTest("break-quarto-md - hr after content (no blank line before)", async () => {
+  await initYamlIntelligenceResourcesFromFilesystem();
+  // HR directly after heading, followed by blank line, then more content with another HR later
+  // The first HR should NOT start a YAML block that consumes content until the second HR
+  const qmd = `---
+title: marimo + quarto
+format: html
+---
+
+# Heading
+---
+
+Some content here.
+
+---
+
+More content.
+`;
+
+  const cells = (await breakQuartoMd(qmd, false)).cells;
+
+  // Check if there's a spurious raw cell after the front matter
+  const rawCells = cells.filter(cell => cell.cell_type === "raw");
+
+  // The HR on line 7 should NOT create a second raw cell
+  // There should only be 1 raw cell (the front matter)
+  assert(rawCells.length === 1, `Expected 1 raw cell (front matter only), got ${rawCells.length}`);
+
+  // All non-front-matter cells should be markdown
+  assert(
+    cells.slice(1).every(cell => cell.cell_type === "markdown"),
+    "All cells after front matter should be markdown"
+  );
+});