Add preview test fixtures and update skill with testing learnings

Test fixtures for T1-T10: single-file Python, project website, keep-ipynb,
plain qmd, and knitr. Project scaffolded via quarto create.

Skill updated with: venv activation requirement, Windows SIGINT limitation
for cleanup testing, simplified background process examples.

Author: cderv

.claude/commands/quarto-preview-test/SKILL.md

@@ -18,15 +18,20 @@ Interactive testing of `quarto preview` with automated browser verification.
 ## Prerequisites
 
 - Quarto dev version built (`./configure.sh` or `./configure.cmd`)
+- Test environment configured (`tests/configure-test-env.sh` or `.ps1`)
 - `/agent-browser` CLI installed (preferred), OR Chrome + Chrome DevTools MCP connected
 
 ## Starting Preview
 
+Preview needs the test venv for Jupyter tests. Activate it first (`tests/.venv`), matching how `run-tests.sh` / `run-tests.ps1` do it.
+
 ```bash
 # Linux/macOS
+source tests/.venv/bin/activate
 ./package/dist/bin/quarto preview <file-or-dir> --no-browser --port 4444
 
-# Windows
+# Windows (Git Bash)
+source tests/.venv/Scripts/activate
 ./package/dist/bin/quarto.cmd preview <file-or-dir> --no-browser --port 4444
 ```
 
@@ -38,21 +43,20 @@ Use `--no-browser` to control browser connection. Use `--port` for a predictable
 ./package/dist/bin/quarto preview <file> --no-browser --port 4444 --log-level debug 2>&1 | tee preview.log
 ```
 
-Filter log entries with `grep` or `jq` for structured output.
-
 ### In background
 
 ```bash
-# Linux/macOS
+# Linux/macOS (after venv activation)
 ./package/dist/bin/quarto preview <file> --no-browser --port 4444 &
 PREVIEW_PID=$!
 # ... run verification ...
 kill $PREVIEW_PID
 
-# Windows (PowerShell)
-$proc = Start-Process -PassThru -NoNewWindow ./package/dist/bin/quarto.cmd preview, <file>, --no-browser, --port, 4444
+# Windows (Git Bash, after venv activation)
+./package/dist/bin/quarto.cmd preview <file> --no-browser --port 4444 &
+PREVIEW_PID=$!
 # ... run verification ...
-Stop-Process $proc
+kill $PREVIEW_PID
 ```
 
 ## Edit-Verify Cycle
@@ -64,7 +68,7 @@ The core test pattern:
 3. Edit source file, wait 3-5 seconds for re-render
 4. Verify content updated in browser
 5. Check filesystem for unexpected artifacts
-6. Stop preview (Ctrl+C or kill), verify cleanup
+6. Stop preview, verify cleanup
 
 ## What to Verify
 
@@ -74,6 +78,10 @@ The core test pattern:
 
 **On filesystem**: No orphaned temp files, cleanup happens on exit.
 
+## Windows Limitations
+
+On Windows, `kill` from Git Bash does not trigger Quarto's `onCleanup` handler (SIGINT doesn't propagate to Windows processes the same way). Cleanup-on-exit verification requires an interactive terminal with Ctrl+C. For automated testing, verify artifacts *during* preview instead.
+
 ## Context Types
 
 Preview behaves differently depending on input:
@@ -92,9 +100,9 @@ See `llm-docs/preview-architecture.md` for the full architecture.
 - Testing render output only (no live preview needed) — use `quarto render`
 - CI environments without browser access
 
-## Test Cases
+## Test Fixtures and Cases
 
-Specific test matrices live in `tests/docs/manual/preview/README.md`. This skill covers the general workflow.
+Test fixtures live in `tests/docs/manual/preview/`. The full test matrix is in `tests/docs/manual/preview/README.md`.
 
 ## Baseline Comparison
 

tests/docs/manual/preview/14281-quarto-ipynb-accumulation.qmd

@@ -36,4 +36,4 @@ with file-save events that cannot be triggered in automated smoke tests.
 
 Edit the line below to trigger re-renders:
 
-Current value: 8
+Current value: 11

tests/docs/manual/preview/keep-ipynb.qmd

@@ -0,0 +1,15 @@
+---
+title: "Keep ipynb Test"
+execute:
+  keep-ipynb: true
+---
+
+## T7: keep-ipynb: true
+
+File should persist after preview exit. No _1 variants during preview.
+
+```{python}
+print("keep-ipynb test")
+```
+
+Edit counter: 0

tests/docs/manual/preview/knitr.qmd

@@ -0,0 +1,14 @@
+---
+title: "Knitr Test"
+engine: knitr
+---
+
+## T10: R/knitr engine
+
+No .quarto_ipynb should be created. Knitr does not use Jupyter.
+
+```{r}
+print("Hello from R")
+```
+
+Edit counter: 0

tests/docs/manual/preview/plain.qmd

@@ -0,0 +1,9 @@
+---
+title: "Plain QMD Test"
+---
+
+## T9: No code cells
+
+No .quarto_ipynb should ever be created.
+
+Edit counter: 0

tests/docs/manual/preview/project-preview/.gitignore

@@ -0,0 +1,2 @@
+/.quarto/
+**/*.quarto_ipynb

tests/docs/manual/preview/project-preview/_quarto.yml

@@ -0,0 +1,19 @@
+project:
+  type: website
+
+website:
+  title: "Preview Test Project"
+  navbar:
+    left:
+      - href: index.qmd
+        text: Home
+      - about.qmd
+
+format:
+  html:
+    theme: cosmo
+    css: styles.css
+    toc: true
+
+
+

tests/docs/manual/preview/project-preview/about.qmd

@@ -0,0 +1,5 @@
+---
+title: "About"
+---
+
+About this site

tests/docs/manual/preview/project-preview/index.qmd

@@ -0,0 +1,11 @@
+---
+title: "Preview Test Project"
+---
+
+## T3/T4: Project preview with Python cell
+
+```{python}
+print("Hello from project preview")
+```
+
+Edit counter: 0

tests/docs/manual/preview/project-preview/styles.css

@@ -0,0 +1 @@
+/* css styles */