feat(cli): add docs (#4837)

feat(cli): add docs

docs/README.md

@@ -23,6 +23,7 @@ Playwright is a library to automate [Chromium](https://www.chromium.org/Home), [
     - [Core concepts](./core-concepts.md)
     - [Debugging](./debug.md)
     - [Supported languages](./languages.md)
+    - [Using Playwright CLI](./cli.md)
 1. Guides
     - [Selectors](./selectors.md)
     - [Input](./input.md)

docs/cli.md

@@ -0,0 +1,157 @@
+# Playwright CLI
+
+Playwright comes with the command line tools that run via `npx` or as a part of the `npm` scripts.
+
+<!-- GEN:toc -->
+- [Usage](#usage)
+- [Generate code](#generate-code)
+- [Open pages](#open-pages)
+  * [Emulate devices](#emulate-devices)
+  * [Emulate color scheme and viewport size](#emulate-color-scheme-and-viewport-size)
+  * [Emulate geolocation, language and timezone](#emulate-geolocation-language-and-timezone)
+- [Inspect selectors](#inspect-selectors)
+    - [playwright.$(selector)](#playwrightselector)
+    - [playwright.$$(selector)](#playwrightselector-1)
+    - [playwright.inspect(selector)](#playwrightinspectselector)
+    - [playwright.selector(element)](#playwrightselectorelement)
+- [Take screenshot](#take-screenshot)
+- [Generate PDF](#generate-pdf)
+- [Known limitations](#known-limitations)
+<!-- GEN:stop -->
+
+## Usage
+
+```sh
+$ npx playwright --help
+```
+
+Running from `package.json` script
+```json
+{
+  "scripts": {
+    "help": "playwright --help"
+  }
+}
+```
+
+## Generate code
+
+```sh
+$ npx playwright codegen wikipedia.org
+```
+
+Run `codegen` and perform actions in the browser. Playwright CLI will generate JavaScript code for the user interactions. `codegen` will attempt to generate resilient text-based selectors.
+
+<img src="https://user-images.githubusercontent.com/284612/92536033-7e7ebe00-f1ed-11ea-9e1a-7cbd912e3391.gif">
+
+## Open pages
+
+With `open`, you can use Playwright bundled browsers to browse web pages. Playwright provides cross-platform WebKit builds that can be used to reproduce Safari rendering across Windows, Linux and macOS.
+
+```sh
+# Open page in Chromium
+npx playwright open example.com
+```
+
+```sh
+# Open page in WebKit
+npx playwright wk example.com
+```
+
+### Emulate devices
+`open` can emulate mobile and tablet devices ([see all devices](https://github.com/microsoft/playwright/blob/master/src/server/deviceDescriptors.ts)).
+
+```sh
+# Emulate iPhone 11.
+npx playwright --device="iPhone 11" open wikipedia.org
+```
+
+### Emulate color scheme and viewport size
+```sh
+# Emulate screen size and color scheme.
+npx playwright --viewport-size=800,600 --color-scheme=dark open twitter.com
+```
+
+### Emulate geolocation, language and timezone
+```sh
+# Emulate timezone, language & location
+# Once page opens, click the "my location" button to see geolocation in action
+npx playwright --timezone="Europe/Rome" --geolocation="41.890221,12.492348" --lang="it-IT" open maps.google.com
+```
+
+## Inspect selectors
+During `open` or `codegen`, you can use following API inside the developer tools console of any browser.
+
+<img src="https://user-images.githubusercontent.com/284612/92536317-37dd9380-f1ee-11ea-875d-daf1b206dd56.png">
+
+#### playwright.$(selector)
+
+Query Playwright selector, using the actual Playwright query engine, for example:
+
+```js
+> playwright.$('.auth-form >> text=Log in');
+
+<button>Log in</button>
+```
+
+#### playwright.$$(selector)
+
+Same as `playwright.$`, but returns all matching elements.
+
+```js
+> playwright.$$('li >> text=John')
+
+> [<li>, <li>, <li>, <li>]
+```
+
+#### playwright.inspect(selector)
+
+Reveal element in the Elements panel (if DevTools of the respective browser supports it).
+
+```js
+> playwright.inspect('text=Log in')
+```
+
+#### playwright.selector(element)
+
+Generates selector for the given element.
+
+```js
+> playwright.selector($0)
+
+"div[id="glow-ingress-block"] >> text=/.*Hello.*/"
+```
+
+## Take screenshot
+
+```sh
+# See command help
+$ npx playwright screenshot --help
+```
+
+```sh
+# Wait 3 seconds before capturing a screenshot after page loads ('load' event fires)
+npx playwright \
+  --device="iPhone 11" \
+  --color-scheme=dark \
+  screenshot \
+    --wait-for-timeout=3000 \
+    twitter.com twitter-iphone.png
+```
+
+```sh
+# Capture a full page screenshot
+npx playwright screenshot --full-page en.wikipedia.org wiki-full.png
+```
+
+## Generate PDF
+
+PDF generation only works in Headless Chromium.
+
+```sh
+# See command help
+$ npx playwright pdf https://en.wikipedia.org/wiki/PDF wiki.pdf
+```
+
+## Known limitations
+Opening WebKit Web Inspector will disconnect Playwright from the browser. In such cases, code generation will stop.

docs/intro.md

@@ -66,10 +66,10 @@ firefox.launch({ headless: false, slowMo: 50 });
 
 ## Record scripts
 
-[Playwright CLI](https://www.npmjs.com/package/playwright-cli) can be used to record user interactions and generate JavaScript code.
+[Playwright CLI](./cli.md) can be used to record user interactions and generate JavaScript code.
 
-```
-npx playwright-cli codegen wikipedia.org
+```sh
+npx playwright codegen wikipedia.org
 ```
 
 ## TypeScript support