How can I unit test Arduino code?

Question

I'd like to be able to unit test my Arduino code. Ideally I would be able to run any tests without having to upload the code to the Arduino. Are there any tools or libraries out there which can help me with this?

Update: There is an Arduino emulator in development which could be useful but it doesn't yet seem to be ready for use.

Update: AVR Studio from Atmel contains a chip simulator which could be useful but I can't see how I would use it in conjunction with the Arduino IDE.

Answer 1

I am not aware of any platform which can test Arduino code.

However, there is the Fritzing platform, which you can use to model the hardware and later on export PCB diagrams and stuff.

Worth checking.

Answer 2

I have considerable success unit testing my Pic code by abstracting out the hardware access and mocking it in my tests.

For example I abstract PORTA with

#define SetPortA(v) {PORTA = v;}

then SetPortA can easily be mocked, without adding overhead code in the Pic version.

Once the hardware abstraction has been tested a while I soon find that generally code goes from the test rig to the Pic and works first time.

Update:

I use a #include seam for the unit code, #including the unit code in a c++ file for the test rig, and a c file for the target code.

As an example I want to multiplex four 7 segment displays, one port driving the segments and a second selecting the display. The display code interfaces with the displays via SetSegmentData(char) and SetDisplay(char). I can mock these in my c++ test rig and check that I get the data I expect. For the target I use #define so that I get a direct assignment without the overhead of a function call

#define SetSegmentData(x) {PORTA = x;}

Answer 3

In the absence of any pre-existing unit test frameworks for Arduino, I have created ArduinoUnit. Here's a simple Arduino sketch demonstrating its use:

#include <ArduinoUnit.h>

// Create test suite
TestSuite suite;

void setup() {
}

// Create a test called 'addition' in the test suite
test(addition) {
    assertEquals(3, 1 + 2);
}

void loop() {
    // Run test suite, printing results to the serial port
    suite.run();
}

Answer 4

Here's two resources for unit testing embedded code (although neither can be used directly with Arduino sketches).

• Embedded Unit
• This paper discusses ways to unit test embedded code

Answer 5

It seems that emulino would do the job perfectly.

Answer 6

simavr is an AVR simulator using avr-gcc.

It already supports a few ATTiny and ATMega µC, and - according to the author - it's easy to add some more.

In the examples lies simduino, an arduino emulator. It supports running the arduino bootloader and can be programmed with avrdude through socat (a modified netcat).

Answer 7

We are using Arduino boards for data acquisition in a large scientific experiment. Subsequently, we have to support several Arduino boards with different implementations. I wrote python utilities to dynamically load Arduino hex images during unit testing. The code found on the link below supports Windows and OSX via configuration file. To find out where your hex images are placed by the Arduino IDE, hit the shift key before you hit the build (play) button. Hit the shift while hitting upload to find out where your avrdude (command line upload utility) is located on your system / version of Arduino. Alternatively, you can look at the included config files and use your install location (currently on Arduino 0020).

http://github.com/toddstavish/Python-Arduino-Unit-Testing