SimpleArduinoFake is a simple mocking framework for Arduino,, based on FakeIt. Its goal is to allow unit testing of your Arduino project natively, with no Arduino. This supports:

1. Complex testing that might exceed physical board limits. E.g. RAM
2. Unit test coverage, which is not possible on a physical board.

This project is a hard fork of ArduinoFake, with some simplifications and bug fixes:

1. No proxies. Arduino classes (E.g. Stream) are mocked directly rather than via a proxy object, so code is DRY
2. No object slicing
3. No memory leaks
4. More modern code style for a simpler code base: no macros, use of namespaces & no dynamic memory allocation
5. Compiles on Windows, using mingw64.

You should include the following header in your test file:

#include <SimpleArduinoFake.h>

Assuming we have the following arduino code:

// src/main.cpp
void loop()
{
    // turn the LED on (HIGH is the voltage level)
    digitalWrite(LED_BUILTIN, HIGH);
    // wait for a second
    delay(100);
    // turn the LED off by making the voltage LOW
    digitalWrite(LED_BUILTIN, LOW);
     // wait for a second
    delay(100);
}

It can be tested using SimpleArduinoFake:

#include <SimpleArduinoFake.h>

using namespace fakeit;

// test/test_main.cpp
void test_loop(void)
{
	auto &functionFake = SimpleArduinoFake::getContext()._Function;
    
	When(Method(functionFake, digitalWrite)).AlwaysReturn();
    When(Method(functionFake, delay)).AlwaysReturn();

    loop();

    Verify(Method(functionFake, digitalWrite).Using(LED_BUILTIN, HIGH)).Once();
    Verify(Method(functionFake, digitalWrite).Using(LED_BUILTIN, LOW)).Once();
    Verify(Method(functionFake, delay).Using(100)).Exactly(2_Times);
}

Look at the examples or the tests for examples.

If you get a segfault while running your unit tests, eg:

Program errored with 3221225477 code

Check to make sure you have stubbed all the Arduino methods you are calling.

Contributions are welcome:

1. The project uses PlatformIO for building, unit testing and CI.
2. Make sure your changes are covered by unit tests.