-
Notifications
You must be signed in to change notification settings - Fork 1.6k
Device Tests & Coverage Report
Only a subset of this library can be tested reasonably with unit tests. Mocking the serial converter chips would hardly represent their real behavior, so I decided to use tests on real devices where the device is connected to:
- Android executing Android instrumented tests
- Windows/Linux host with a real serial port running a RFC-2217 server
The instrumented test uses the RFC-2217 server to control the other end of the serial line over Wi-Fi.
By default the USB port is used for ADB debugging, but ADB can also use Wi-Fi. To enable Wi-Fi you have to enable it in Android Settings -> Developer options, connect with USB ADB and enable Wi-Fi with adb tcpip 5555, see more details here.
You need python + pyserial 3.4 which includes a rfc2217_server.py. You can install pyserial with pip install serial
On Linux the rfc2217_server.py is typically available in usr/share/doc/python-serial/examples. On Windows you have to take it from github.
On a Raspi 3 you have to configure the PL011-UART instead of the mini-UART for the GPIO pins.
Before executing the test, start the rfc2217 server with: python rfc2217_server.py -v com-port
To see all data apply this patch and use -v -v option.
Over the time I collected various serial breakout boards, but each device comes with a different pin assignment, so I created my own and soldered mini adapters vor every device.
My pin assignment is:
| 1 | 2 | 3 | 4 | 5 |
|---|---|---|---|---|
| GND | TxD | Rxd | n.c. | +5V |
+5V is connected at all serial devices to provide power to other devices that are not self powered.
The Raspi needs a level shifter because it is not 5V tolerant. I used a 74HC21 which is not the most commonly used level shifter, but that's what I found over the weekend in my parts collection. +5V is not connected as the Raspi as it is self powered.
The Arduino Pro Micro has to be programmed with arduino_leonardo_bridge.ino
- Start
rfc2217_server.pyon your Windows/Linux host - Configure the ip address of your rfc2217 server host in
usbSerialForAndroid/build.gradle -> testInstrumentationRunnerArguments -> rfc2217_server_host. Depending on the host type enable/disable the othertestInstrumentationRunnerArguments. - Connect your device
- Start
DeviceTest - When requested, confirm USB permission dialog on your Android device
Tests are sometimes flaky, as they depend on real hardware, which can have varying performance or some data left in receive buffers from previous failing tests. Retrying multiple times, re-attaching the serial device or restarting the rfc2217_server.py typically helps. Else try increasing the timeouts in DeviceTest.java.
Enable apply from: 'coverage.gradle' in usbSerialForAndroid/build.gradle.
Remove previous test results with gradle clean or Android Studio : Menu -> Build -> Clean Project
For each flavor defined in coverage.gradle execute the corresponding createFlavorDebugAndroidTestCoverage task. You can find these tasks in Android Studios Gradle window in the usb-serial-for-android -> usbSerialForAndroid -> other folder. You can show this window with Android Studio : Menu -> View -> Tool Windows -> Gradle.
As tests can be flaky, it's best to first execute DeviceTest as this shows the test results and errors much better and on success execute the createFlavorDebugAndroidTestCoverage task.
Upload coverage reports to codecov.io using the bash uploader. On Windows execute in Git Bash. I tried to merge the test reports locally, but the recommended jacocoTestReport task for whatever reason did nothing.