Bugfix/issue 3896 (#3910)

* only check contents if length > 0. Closes #3896

Author: cscheid

news/changelog-1.3.md

@@ -3,6 +3,7 @@
 ## Jupyter Notebooks
 
 - Add support for embedding cell outputs in quarto documents using `{{< embed >}}`. You can address cells by Id, Tag, or label, such as `{{< embed mynotebook.ipynb#fig-output >}}` which would embed the output of a cell with the label `fig-output`). You can also provide a list of ids like `{{< embed mynotebook.ipynb#fig-output,tbl-out >}}`.
+- Only attempt to postprocess `text/plain` output if it's nonempty ([#3896](https://github.com/quarto-dev/quarto-cli/issues/3896)).
 
 ## Code Annotation
 

src/core/jupyter/jupyter.ts

@@ -1061,7 +1061,9 @@ async function mdFromCodeCell(
     if (output.output_type === "execute_result") {
       const textPlain = (output as JupyterOutputDisplayData).data
         ?.[kTextPlain] as string[] | undefined;
-      if (textPlain && textPlain[0].startsWith("[<matplotlib")) {
+      if (
+        textPlain && textPlain.length && textPlain[0].startsWith("[<matplotlib")
+      ) {
         return false;
       }
     }

tests/docs/smoke-all/2023/01/09/file_1.ipynb

@@ -0,0 +1,79 @@
+{
+ "cells": [
+  {
+   "cell_type": "raw",
+   "id": "dbd7953c",
+   "metadata": {},
+   "source": [
+    "---\n",
+    "title: Some title\n",
+    "author: Some name\n",
+    "date: '2022-01-09'\n",
+    "format:\n",
+    "  html:\n",
+    "    toc: true\n",
+    "    toc-depth: 2\n",
+    "    code-fold: true\n",
+    "    self-contained: true\n",
+    "---"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "id": "54f3e4bb",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": []
+     },
+     "execution_count": 16,
+     "metadata": {},
+     "output_type": "execute_result"
+    },
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "┌─────────┬─────────┬────────┬────────┐\n",
+      "│\u001b[1m         \u001b[0m│\u001b[1m cv_elpd \u001b[0m│\u001b[1m cv_avg \u001b[0m│\u001b[1m weight \u001b[0m│\n",
+      "├─────────┼─────────┼────────┼────────┤\n",
+      "│\u001b[1m model_2 \u001b[0m│    0.00 │   0.00 │   0.79 │\n",
+      "│\u001b[1m model_3 \u001b[0m│   -1.51 │  -0.01 │   0.18 │\n",
+      "│\u001b[1m model_1 \u001b[0m│   -3.28 │  -0.02 │   0.03 │\n",
+      "│\u001b[1m model_4 \u001b[0m│  -13.14 │  -0.07 │   0.00 │\n",
+      "└─────────┴─────────┴────────┴────────┘\n"
+     ]
+    }
+   ],
+   "source": [
+    "loo_compare(loo_model1, loo_model2, loo_model3, loo_model4)\n",
+    "# Past results\n",
+    "# ┌─────────┬─────────┬────────┬────────┐\n",
+    "# │         │ cv_elpd │ cv_avg │ weight │\n",
+    "# ├─────────┼─────────┼────────┼────────┤\n",
+    "# │ model_2 │    0.00 │   0.00 │   0.84 │\n",
+    "# │ model_3 │   -1.77 │  -0.01 │   0.14 │\n",
+    "# │ model_1 │   -3.70 │  -0.02 │   0.02 │\n",
+    "# │ model_4 │  -13.94 │  -0.07 │   0.00 │\n",
+    "# └─────────┴─────────┴────────┴────────┘"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "julia6 1.8.4",
+   "language": "julia",
+   "name": "julia6-1.8"
+  },
+  "language_info": {
+   "file_extension": ".jl",
+   "mimetype": "application/julia",
+   "name": "julia",
+   "version": "1.8.4"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

tests/smoke/smoke-all.test.ts

@@ -26,6 +26,8 @@ import {
 } from "../verify.ts";
 import { readYamlFromMarkdown } from "../../src/core/yaml.ts";
 import { outputForInput } from "../utils.ts";
+import { jupyterToMarkdown } from "../../src/core/jupyter/jupyter.ts";
+import { jupyterNotebookToMarkdown } from "../../src/command/convert/jupyter.ts";
 
 async function fullInit() {
   await initYamlIntelligenceResourcesFromFilesystem();
@@ -119,7 +121,7 @@ function resolveTestSpecs(
 const globOutput = Deno.args.length
   ? expandGlobSync(Deno.args[0])
   : expandGlobSync(
-    "docs/smoke-all/**/*.qmd",
+    "docs/smoke-all/**/*.{qmd,ipynb}",
   );
 
 await initYamlIntelligenceResourcesFromFilesystem();
@@ -129,7 +131,9 @@ for (
 ) {
   const input = fileName;
 
-  const metadata = readYamlFromMarkdown(Deno.readTextFileSync(input));
+  const metadata = input.endsWith("qmd")
+    ? readYamlFromMarkdown(Deno.readTextFileSync(input))
+    : readYamlFromMarkdown(await jupyterNotebookToMarkdown(input, false));
   const testSpecs = [];
 
   if (hasTestSpecs(metadata)) {