# Rstudio Run Playwright Tests

> How to run RStudio Playwright tests in Desktop and Server modes. Use this skill whenever the user asks to run, execute, or launch Playwright tests against RStudio - whether on Desktop (local) or Server (remote). Also use when the user asks about the test command, environment variables, or how to point tests at a server URL. Trigger on phrases like "run the test", "execute on server", "run it on desktop", "run against <IP>", or any request involving npx playwright test for the RStudio test suite.

- Skill: `rstudio/rstudio-run-playwright-tests` (Agent Skill)
- Install (CLI): `npx skillmds@latest add rstudio/rstudio-run-playwright-tests`
- Raw SKILL.md: https://api.skillmd.com/api/skills/rstudio/rstudio-run-playwright-tests/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: rstudio (https://skillmd.com/u/rstudio)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/rstudio/rstudio-run-playwright-tests

---


# Running RStudio Playwright Tests

Run from `e2e/rstudio/`. Setup, env vars, tags, sandbox, external-server config,
and the cross-env / dotenv helpers all live in `e2e/rstudio/README.md` -- open
it when you need any of that.

## The four run modes

| Mode | Command | Platforms |
|------|---------|-----------|
| Installed desktop | `npm run test:desktop` | macOS, Linux, Windows |
| Dev desktop build | `npm run test:desktop-dev` | macOS, Linux, Windows |
| Installed server | `npm run test:server` | Linux |
| Dev server build | `npm run test:server-dev` | macOS, Linux |

Append a test path or Playwright flags after the script name:

```bash
npm run test:desktop -- tests/path/to/test.test.ts
npm run test:server-dev -- -g "test name here"
```

### `test:desktop-dev` prerequisites (from repo root)

1. `cmake --build build` -- C++ session
2. `(cd src/gwt && ant draft)` -- GWT transpile (2-5 min; rerun after Java edits)
3. `(cd src/node/desktop && npm ci)` -- Electron deps

In a secondary worktree, run `scripts/bootstrap-worktree.sh` instead of steps
1 and 3: when the worktree has no configured `build/`, the wrapper skips the
cmake build and automatically points the launcher at the worktree's
`build-dev-shim` (worktree GWT + main checkout's built session). Step 2 is
still on you -- the wrapper only warns when `src/gwt/src` is newer than the
precompiled bootstrap. Do NOT symlink the worktree's `build/` at the main
checkout's: its conf would silently serve main's GWT.

Tests that exercise `doRestart()` (e.g. uninstall Posit Assistant) aren't
supported in this mode.

## Test running protocol

Before the first run in a conversation, pick a mode -- ask the user which of
the four they want (use `AskUserQuestion` if available), filtering out modes
unsupported by the host platform. If a `build/` directory exists at the repo
root, list `test:desktop-dev` first in the options. Then run the tests
directly; don't prompt for approval before kicking off the run. Prefer
`npm run ...` over raw `npx playwright test`.

After the first run, don't re-ask to re-run the same file in the same mode --
just go. Switching modes (not files) warrants a fresh mode-pick.

## Profiling a slow test

When a test passes but is slower than expected, don't guess at the cause --
capture a trace and read per-action timing. Re-run with `--trace on`, then
unzip the `trace.zip` and pair the `before`/`after` events in `test.trace` by
`callId` to rank actions by duration. The full recipe (with a ready-to-run
Node parser) is in the "Profiling a slow test" section of
`e2e/rstudio/README.md`.

Common culprit it surfaces: a value-reading action (e.g. `locator.inputValue()`)
on an element not yet in the DOM blocks on the action timeout -- probe with
`locator.count()` instead and open the editor/popup before reading from it.