code-server/lib/vscode/test/smoke/README.md

# VS Code Smoke Test

Make sure you are on **Node v12.x**.

### Quick Overview

```bash
# Build extensions in repo (if needed)
yarn && yarn compile

# Install Dependencies and Compile
yarn --cwd test/smoke

# Prepare OSS in repo*
node build/lib/preLaunch.js

# Dev (Electron)
yarn smoketest

# Dev (Web - Must be run on distro)
yarn smoketest --web --browser [chromium|webkit]

# Build (Electron)
yarn smoketest --build <path to latest version> --stable-build <path to stable version>

# Build (Web - read instructions below)
yarn smoketest --build <path to server web build> --web --browser [chromium|webkit]

# Remote (Electron)
yarn smoketest --build <path to latest version> --remote
```

\* This step is necessary only when running without `--build` and OSS doesn't already exist in the `.build/electron` directory.

### Running for a release (Endgame)

You must always run the smoketest version that matches the release you are testing. So, if you want to run the smoketest for a release build (e.g. `release/1.22`), you need to check out that version of the smoke tests too:

```bash
git fetch
git checkout release/1.22
yarn && yarn compile
yarn --cwd test/smoke
```

#### Electron with --build and --stable-build

In addition to the vscode repository, you will need the latest build and the previous stable build, so that the smoketest can test data migration.

The recommended way to make these builds available for the smoketest is by downloading their archive versions (\*.zip) from the **[builds page](https://builds.code.visualstudio.com/)**, and extracting
them into two folders (e.g. with 'Extract All' on Windows). Pass the **absolute paths** of those folders to the smoketest as follows:

```bash
yarn smoketest --build <path to latest version> --stable-build <path to stable version>
```

#### Web

There is no support for testing an old version to a new one yet.
Instead, simply configure the `--build` command line argument to point to the absolute path of the extracted server web build folder (e.g. `<rest of path here>/vscode-server-darwin-web` for macOS). The server web build is available from the builds page (see previous subsection).

**macOS**: if you have downloaded the server with web bits, make sure to run the following command before unzipping it to avoid security issues on startup:

```bash
xattr -d com.apple.quarantine <path to server with web folder zip>
```

**Note**: make sure to point to the server that includes the client bits!

### Debug

- `--verbose` logs all the low level driver calls made to Code;
- `-f PATTERN` (alias `-g PATTERN`) filters the tests to be run. You can also use pretty much any mocha argument;
- `--screenshots SCREENSHOT_DIR` captures screenshots when tests fail.

### Develop

```bash
cd test/smoke
yarn watch
```

## Pitfalls

- Beware of workbench **state**. The tests within a single suite will share the same state.

- Beware of **singletons**. This evil can, and will, manifest itself under the form of FS paths, TCP ports, IPC handles. Whenever writing a test, or setting up more smoke test architecture, make sure it can run simultaneously with any other tests and even itself.	All test suites should be able to run many times in parallel.

- Beware of **focus**. **Never** depend on DOM elements having focus using `.focused` classes or `:focus` pseudo-classes, since they will lose that state as soon as another window appears on top of the running VS Code window. A safe approach which avoids this problem is to use the `waitForActiveElement` API. Many tests use this whenever they need to wait for a specific element to _have focus_.

- Beware of **timing**. You need to read from or write to the DOM... but is it the right time to do that? Can you 100% guarantee that `input` box will be visible at that point in time? Or are you just hoping that it will be so? Hope is your worst enemy in UI tests. Example: just because you triggered Quick Access with `F1`, it doesn't mean that it's open and you can just start typing; you must first wait for the input element to be in the DOM as well as be the current active element.

- Beware of **waiting**. **Never** wait longer than a couple of seconds for anything, unless it's justified. Think of it as a human using Code. Would a human take 10 minutes to run through the Search viewlet smoke test? Then, the computer should even be faster. **Don't** use `setTimeout` just because. Think about what you should wait for in the DOM to be ready and wait for that instead.