| 1 | `async`/`await` and the Web Driver Control Flow
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| 2 | ===============================================
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| 3 |
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| 4 | The Web Driver Control Flow is used to synchronize your commands so they reach
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| 5 | the browser in the correct order (see [control-flow.md](
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| 6 | ../../docs/control-flow.md) for details). In the future, the control flow is
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| 7 | being removed, however (see [github issue](
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| 8 | https://github.com/SeleniumHQ/selenium/issues/2969) for details). Instead of
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| 9 | the control flow, you can synchronize your commands with promise chaining or the
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| 10 | upcomming ES7 feature `async`/`await`. However, you cannot use a mix of
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| 11 | `async`/`await` and the control flow: `async`/`await` causes the control flow to
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| 12 | become unreliable (see [github issue](
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| 13 | https://github.com/SeleniumHQ/selenium/issues/3037)). So if you `async`/`await`
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| 14 | anywhere in a spec, you should use `await` or promise chaining to handle all
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| 15 | asynchronous activity (e.g. any command interacting with the browser) for the
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| 16 | rest of that test.
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| 17 |
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| 18 | In the near future there will be an option to disable the Web Driver control
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| 19 | flow entierly (see https://github.com/angular/protractor/issues/3691). If you
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| 20 | are using `async`/`await`, it is highly recommended that you disable the Web
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| 21 | Driver control flow.
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| 22 |
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| 23 |
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| 24 | Compiling `async`/`await` syntax
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| 25 | ================================
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| 26 |
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| 27 | `async`/`await` syntax is currently accessible via typescript if you compile
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| 28 | using `tsc -t ES2015 <files>`. You can also compile it using [regenerator](
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| 29 | https://github.com/facebook/regenerator).
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