convert - preserve markdown after yaml in raw cells

news/changelog-1.7.md

@@ -37,6 +37,10 @@ All changes included in 1.7:
 
 - ([#11608](https://github.com/quarto-dev/quarto-cli/pull/11608)): Do not issue error message when calling `quarto check info`.
 
+## `quarto convert`
+
+- ([#12042](https://github.com/quarto-dev/quarto-cli/issues/12042)): Preserve Markdown content that follows YAML metadata in a `raw` .ipynb cell.
+
 ## `html` format
 
 - ([#11860](https://github.com/quarto-dev/quarto-cli/issues/11860)): ES6 modules that import other local JS modules in documents with `embed-resources: true` are now correctly embedded.

src/command/convert/jupyter.ts

@@ -30,6 +30,7 @@ import {
   jupyterCellSrcAsLines,
   jupyterCellSrcAsStr,
 } from "../../core/jupyter/jupyter-shared.ts";
+import { assert } from "testing/asserts";
 
 export async function markdownToJupyterNotebook(
   file: string,
@@ -71,11 +72,15 @@ export async function jupyterNotebookToMarkdown(
         case "raw":
           // see if this is the front matter
           if (frontMatter === undefined) {
-            frontMatter = partitionYamlFrontMatter(
-              jupyterCellSrcAsStr(cell),
-            )?.yaml;
-            if (!frontMatter) {
-              md.push(...mdFromRawCell(cellWithOptions));
+            const { yaml: cellYaml, markdown: cellMarkdown } =
+              partitionYamlFrontMatter(
+                jupyterCellSrcAsStr(cell),
+              ) || {};
+            if (cellYaml) {
+              frontMatter = cellYaml;
+            }
+            if (cellMarkdown) {
+              md.push(cellMarkdown);
             }
           } else {
             md.push(...mdFromRawCell(cellWithOptions));
@@ -130,14 +135,22 @@ export async function jupyterNotebookToMarkdown(
     }
   }
 
+  // if we found front matter, then the markdown source will start with enough
+  // newlines for the front matter to have been detected in the first place.
+  // So we only need to add newlines if there was no front matter.
+  //
+  // If this invariant breaks, we have a bug of some kind, so let's just assert it
+  assert(frontMatter || !mdSource.match(/^\n\n/));
+  const maybeYamlMdBreak = frontMatter ? "" : "\n\n";
+
   // return yaml + markdown
   const yamlText = stringify(yaml, {
     indent: 2,
     lineWidth: -1,
     sortKeys: false,
     skipInvalid: true,
   });
-  return `---\n${yamlText}---\n\n${mdSource}`;
+  return `---\n${yamlText}---${maybeYamlMdBreak}${mdSource}`;
 }
 
 async function mdFromCodeCell(

tests/docs/convert/issue-12042.ipynb

@@ -0,0 +1,32 @@
+{
+  "cells": [
+    {
+      "cell_type": "markdown",
+      "metadata": {},
+      "source": [
+        "---\n",
+        "title: My Document\n",
+        "format: html\n",
+        "jupyter: python3\n",
+        "keep-ipynb: true\n",
+        "---\n",
+        "\n",
+        "\n",
+        "\n",
+        "## Introduction\n",
+        "\n",
+        "Here I place some text."
+      ]
+    }
+  ],
+  "metadata": {
+    "kernelspec": {
+      "name": "python3",
+      "language": "python",
+      "display_name": "Python 3 (ipykernel)",
+      "path": "/Users/cscheid/virtualenvs/homebrew-python3/share/jupyter/kernels/python3"
+    }
+  },
+  "nbformat": 4,
+  "nbformat_minor": 4
+}

tests/smoke/convert/convert-issue-12042.test.ts

@@ -0,0 +1,36 @@
+/*
+* convert-backticks.test.ts
+*
+* Copyright (C) 2020-2024 Posit Software, PBC
+*
+*/
+import { existsSync } from "../../../src/deno_ral/fs.ts";
+import {
+  ExecuteOutput,
+  testQuartoCmd,
+} from "../../test.ts";
+import { assert } from "testing/asserts";
+
+(() => {
+  const input = "docs/convert/backticks.ipynb";
+  testQuartoCmd(
+    "convert",
+    ["docs/convert/issue-12042.ipynb"],
+    [
+      {
+        name: "convert-markdown-after-yaml",
+        verify: async (outputs: ExecuteOutput[]) => {
+          const txt = Deno.readTextFileSync("docs/convert/issue-12042.qmd");
+          assert(txt.includes("Here I place some text."), "Markdown text not found in output");
+        }
+      }
+    ],
+    {
+      teardown: async () => {
+        if (existsSync("docs/convert/issue-12042.qmd")) {
+          Deno.removeSync("docs/convert/issue-12042.qmd");
+        }
+      }
+    },
+  );
+})();