Fix preview crash on re-render (BadResource error)

news/changelog-1.9.md

@@ -125,6 +125,10 @@ All changes included in 1.9:
 
 - ([#4426](https://github.com/quarto-dev/quarto-cli/issues/4426)): New `quarto install verapdf` command installs [veraPDF](https://verapdf.org/) for PDF/A and PDF/UA validation. When verapdf is available, PDFs created with the `pdf-standard` option are automatically validated for compliance. Also supports `quarto uninstall verapdf`, `quarto update verapdf`, and `quarto tools`.
 
+### `preview`
+
+- ([#13804](https://github.com/quarto-dev/quarto-cli/pull/13804)): Fix intermittent preview crashes during re-renders by properly managing project context lifecycle. Resolves issues with missing temporary directories and `quarto_ipynb` files when editing notebooks and qmd files together.
+
 ## Extensions
 
 - Metadata and brand extensions now work without a `_quarto.yml` project. (Engine extensions do too.) A temporary default project is created in memory.

src/command/preview/preview.ts

@@ -4,7 +4,7 @@
  * Copyright (C) 2020-2022 Posit Software, PBC
  */
 
-import { info, warning } from "../../deno_ral/log.ts";
+import { debug, info, warning } from "../../deno_ral/log.ts";
 import {
   basename,
   dirname,
@@ -424,6 +424,15 @@ export async function renderForPreview(
   pandocArgs: string[],
   project?: ProjectContext,
 ): Promise<RenderForPreviewResult> {
+  // Invalidate file cache for the file being rendered so changes are picked up.
+  // The project context persists across re-renders in preview mode, but the
+  // fileInformationCache contains file content that needs to be refreshed.
+  // TODO(#13955): Consider adding a dedicated invalidateForFile() method on ProjectContext
+  if (project?.fileInformationCache) {
+    debug(`[renderForPreview] Invalidating file information cache for ${file}`);
+    project.fileInformationCache.delete(file);
+  }
+
   // render
   const renderResult = await render(file, {
     services,
@@ -485,8 +494,6 @@ export async function renderForPreview(
     [],
   ));
 
-  renderResult.context.cleanup();
-
   return {
     file,
     format: renderResult.files[0].format,

src/core/sass/cache.ts

@@ -145,7 +145,9 @@ class SassCache implements Cloneable<SassCache> {
   // add a cleanup method to register a cleanup handler
   cleanup(temp: TempContext | undefined) {
     const registerCleanup = temp ? temp.onCleanup : onCleanup;
+    const cachePath = this.path;
     registerCleanup(() => {
+      log.debug(`SassCache cleanup executing for ${cachePath}`);
       try {
         this.kv.close();
         if (temp) safeRemoveIfExists(this.path);