# Testing

Tests describe the behaviour of a driver and can be used to help with development. They are also useful in describing the intended usage of a driver.

For example usage, see:

* [Extron DXP spec](https://github.com/acaprojects/aca-device-modules/blob/master/modules/extron/switcher/dxp_spec.rb)
* [Denon BluRay spec](https://github.com/acaprojects/aca-device-modules/blob/master/modules/denon/bluray/dn500bd_spec.rb)
* [ClearOne Converge spec](https://github.com/acaprojects/aca-device-modules/blob/master/modules/clear_one/converge_spec.rb)
  * Waits for login prompt before processing commands
* [Panasonic Projector spec](https://github.com/acaprojects/aca-device-modules/blob/master/modules/panasonic/projector/tcp_spec.rb)
  * Waits for encryption key
  * Injects password before transmitting data

## Checking Values

The Engine test framework uses [rspec-expectations](https://github.com/rspec/rspec-expectations) for verifying status variables and command results returned expected values.

## Helper Functions

| Helper                  | Arguments                        | Description                                                                          |
| ----------------------- | -------------------------------- | ------------------------------------------------------------------------------------ |
| `transmit` / `responds` | string / hex string / byte array | emulates a device sending data to the module                                         |
| `exec`                  | `function_name, *arguments`      | calls the function requested on the module with the arguments provided               |
| `should_send`           | string / hex string / byte array | this is the data the driver is expected to send to the device                        |
| `result`                |                                  | provides access to the result of the last executed request                           |
| `status`                |                                  | provides access to the current status of the driver                                  |
| `temporary_disconnect`  |                                  | emulates a connection drop followed by re-establishment                              |
| `device_offline`        |                                  | emulates a connection drop where communications have failed to be re-established     |
| `device_online`         |                                  | emulates connection re-establishment. Should only be called after a `device_offline` |
| `wait_tick`             | times = 1                        | resumes the test after the specified number of ticks through the event loop          |
| `wait`                  | milliseconds                     | resumes the test after waiting the specified amount of time                          |

## Debugging

[Byebug](https://github.com/deivid-rodriguez/byebug) makes it possible to

1. Step through code one line at a time
2. Pause the driver at some event or specified instruction, to examine the current state.
3. Interact with the state by executing code dynamically at the breakpoint

Byebug Resources:

* [Usage Tutorial](https://www.sitepoint.com/the-ins-and-outs-of-debugging-ruby-with-byebug/)
* [Video Tutorial](https://www.youtube.com/watch?v=toZrovVX4ug)

## Running Tests

There is a rake task where you can specify the file containing the driver spec. Drivers themselves are resolved and loaded internally, as they would be in a running system.

* `rake module:test['../aca-device-modules/modules/extron/switcher/dxp_spec.rb']`

To simplify the process of running tests, when using the [development setup](https://github.com/acaprojects/setup-dev), you can run tests in the browser.

* Your system is scanned and spec files are listed on the right
* Selecting a spec will attempt to load the driver file
  * You will see any load errors that occur (such as syntax errors)
  * Discovery information is listed in a table
  * The test is executed in an interactive console, allowing for interactive debugging
  * Click the refresh icon to re-run the test at any point

![](https://user-images.githubusercontent.com/368013/28649530-e6ecf98c-72b8-11e7-86d8-1977aef69007.png)


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