Gem Version Build Status Documentation

ArduinoCI Ruby gem (arduino_ci)

Arduino CI is a Ruby gem for executing Continuous Integration (CI) tests on an Arduino library -- both locally and as part of a service like Travis CI.

Installation In Your GitHub Project And Using Travis CI

Add a file called Gemfile (no extension) to your Arduino project:

source 'https://rubygems.org' gem 'arduino_ci' 

Next, you need this in .travis.yml

sudo: false language: ruby script: - bundle install - bundle exec arduino_ci_remote.rb 

That's literally all there is to it on the repository side. You'll need to go to https://travis-ci.org/profile/ and enable testing for your Arduino project. Once that happens, you should be all set. The script will test all example projects of the library and all unit tests.

Note: arduino_ci_remote.rb expects to be run from the root directory of your Arduino project library.

Unit tests in test/

All .cpp files in the test/ directory of your Arduino library are assumed to contain unit tests. Each and every one will be compiled and executed on its own.

The most basic unit test file is as follows:

#include <ArduinoUnitTests.h> #include "../do-something.h" unittest(your_test_name) { assertEqual(4, doSomething()); } unittest_main() 

This test defines one unittest (a macro provided by ArduionUnitTests.h), called your_test_name, which makes some assertions on the target library. The unittest_main() is a macro for the int main() boilerplate required for unit testing.

Using GODMODE

Complete control of the Arduino environment is available in your unit tests through a construct called GODMODE().

unittest(example_godmode_stuff) { GodmodeState* state = GODMODE(); // get access to the state state->reset(); // does a full reset of the state. state->resetClock(); // - you can reset just the clock (to zero) state->resetPins(); // - or just the pins state->micros = 1; // manually set the clock such that micros() returns 1 state->digitalPin[4]; // tells you the commanded state of digital pin 4 state->digitalPin[4] = HIGH; // digitalRead(4) will now return HIGH state->analogPin[3]; // tells you the commanded state of analog pin 3 state->analogPin[3] = 99; // analogRead(3) will now return 99 } 

Pin Histories

Of course, it's possible that your code might flip the bit more than once in a function. For that scenario, you may want to examine the history of a pin's commanded outputs:

unittest(pin_history) { GodmodeState* state = GODMODE(); int myPin = 3; state->reset(); // pin will start LOW digitalWrite(myPin, HIGH); digitalWrite(myPin, LOW); digitalWrite(myPin, LOW); digitalWrite(myPin, HIGH); digitalWrite(myPin, HIGH); // pin history is queued in case we want to analyze it later. // we expect 6 values in that queue. assertEqual(6, state->digitalPin[1].size()); bool expected[6] = {LOW, HIGH, LOW, LOW, HIGH, HIGH}; bool actual[6]; // convert history queue into an array so we can verify it int numMoved = state->digitalPin[myPin].toArray(actual, 6); assertEqual(6, numMoved); // verify each element for (int i = 0; i < 6; ++i) { assertEqual(expected[i], actual[i]); } } 

Pin Futures

Reading the pin more than once per function is also a possibility. In that case, we want to queue up a few values for the digitalRead or analogRead to find.

unittest(pin_read_history) { GodmodeState* state = GODMODE(); state->reset(); int future[6] = {33, 22, 55, 11, 44, 66}; state->analogPin[1].fromArray(future, 6); for (int i = 0; i < 6; ++i) { assertEqual(future[i], analogRead(1)); } // for digital pins, we have the added possibility of specifying // a stream of input bytes encoded as ASCII bool bigEndian = true; state->digitalPin[1].fromAscii("Yo", bigEndian); // digitial history as serial data, big-endian bool expectedBits[16] = { 0, 1, 0, 1, 1, 0, 0, 1, // Y 0, 1, 1, 0, 1, 1, 1, 1 // o }; for (int i = 0; i < 16; ++i) { assertEqual(expectedBits[i], digitalRead(1)); } } 

Serial Data

Basic input and output verification of serial port data can be done as follows:

unittest(reading_writing_serial) { GodmodeState* state = GODMODE(); state->serialPort[0].dataIn = ""; // the queue of data waiting to be read state->serialPort[0].dataOut = ""; // the history of data written // When there is no data, nothing happens assertEqual(-1, Serial.peek()); assertEqual("", state->serialPort[0].dataIn); assertEqual("", state->serialPort[0].dataOut); // if we put data on the input and peek at it, we see the value and it's not consumed state->serialPort[0].dataIn = "a"; assertEqual('a', Serial.peek()); assertEqual("a", state->serialPort[0].dataIn); assertEqual("", state->serialPort[0].dataOut); // if we read the input, we see the value and it's consumed assertEqual('a', Serial.read()); assertEqual("", state->serialPort[0].dataIn); assertEqual("", state->serialPort[0].dataOut); // when we write data, it shows up in the history -- the output buffer Serial.write('b'); assertEqual("", state->serialPort[0].dataIn); assertEqual("b", state->serialPort[0].dataOut); // when we print more data, note that the history // still contains the first thing we wrote Serial.print("cdefg"); assertEqual("", state->serialPort[0].dataIn); assertEqual("bcdefg", state->serialPort[0].dataOut); } 

A more complicated example: working with serial port IO. Let's say I have the following function:

void smartLightswitchSerialHandler(int pin) { if (Serial.available() > 0) { int incomingByte = Serial.read(); int val = incomingByte == '0' ? LOW : HIGH; Serial.print("Ack "); digitalWrite(pin, val); Serial.print(String(pin)); Serial.print(" "); Serial.print((char)incomingByte); } } 

This function has 3 side effects: it drains the serial port's receive buffer, affects a pin, and puts data in the serial port's send buffer. Or, if the receive buffer is empty, it does nothing at all.

unittest(does_nothing_if_no_data) { // configure initial state GodmodeState* state = GODMODE(); int myPin = 3; state->serialPort[0].dataIn = ""; state->serialPort[0].dataOut = ""; state->digitalPin[myPin] = LOW; // execute action smartLightswitchSerialHandler(myPin); // assess final state assertEqual(LOW, state->digitalPin[myPin]); assertEqual("", state->serialPort[0].dataIn); assertEqual("", state->serialPort[0].dataOut); } unittest(two_flips) { GodmodeState* state = GODMODE(); int myPin = 3; state->serialPort[0].dataIn = "10junk"; state->serialPort[0].dataOut = ""; state->digitalPin[myPin] = LOW; smartLightswitchSerialHandler(myPin); assertEqual(HIGH, state->digitalPin[myPin]); assertEqual("0junk", state->serialPort[0].dataIn); assertEqual("Ack 3 1", state->serialPort[0].dataOut); state->serialPort[0].dataOut = ""; smartLightswitchSerialHandler(myPin); assertEqual(LOW, state->digitalPin[myPin]); assertEqual("junk", state->serialPort[0].dataIn); assertEqual("Ack 3 0", state->serialPort[0].dataOut); } 

Pin History as ASCII

For additional complexity, there are some cases where you want to use a pin as a serial port. There are history functions for that too.

 int myPin = 3; // digitial history as serial data, big-endian bool bigEndian = true; bool binaryAscii[24] = { 0, 1, 0, 1, 1, 0, 0, 1, // Y 0, 1, 1, 0, 0, 1, 0, 1, // e 0, 1, 1, 1, 0, 0, 1, 1 // s }; // "send" these bits for (int i = 0; i < 24; digitalWrite(myPin, binaryAscii[i++])); // The first bit in the history is the initial value, which we will ignore int offset = 1; // We should be able to parse the bits as ascii assertEqual("Yes", state->digitalPin[myPin].toAscii(offset, bigEndian)); 

Instead of queueing bits as ASCII for future use with toAscii, you can send those bits directly (and immediately) to the output using outgoingFromAscii. Likewise, you can reinterpret/examine (as ASCII) the bits you have previously queued up by calling incomingToAscii on the PinHistory object.

Interactivity of "Devices" with Observers

Even pin history and input/output buffers aren't capable of testing interactive code. For example, queueing the canned responses from a serial device before the requests are even sent to it is not a sane test environment; the library under test will see the entire future waiting for it on the input pin instead of a buffer that fills and empties over time. This calls for something more complicated.

In this example, we create a simple class to emulate a Hayes modem. (For more information, dig into the DataStreamObserver code on which DeviceUsingBytes is based.

class FakeHayesModem : public DeviceUsingBytes { public: String mLast; FakeHayesModem() : DeviceUsingBytes() { mLast = ""; addResponseLine("AT", "OK"); addResponseLine("ATV1", "NO CARRIER"); } virtual ~FakeHayesModem() {} virtual void onMatchInput(String output) { mLast = output; } }; unittest(modem_hardware) { GodmodeState* state = GODMODE(); state->reset(); FakeHayesModem m; m.attach(&Serial); Serial.write("AT\n"); assertEqual("AT\n", state->serialPort[0].dataOut); assertEqual("OK\n", m.mLast); } 

Note that instead of setting mLast = output in the onMatchInput() function for test purposes, we could just as easily queue some bytes to state->serialPort[0].dataIn for the library under test to find on its next peek() or read(). Or we could execute some action on a digital or analog input pin; the possibilities are fairly endless in this regard, although you will have to define them yourself -- from scratch -- extending the DataStreamObserver class to emulate your physical device.

Overriding default build behavior

You can add .arduino-ci.yml files to the project directory (which will then apply to both test/ and examples/), as well as to the test/ directory and each example directory in examples/. All defined fields can be overridden.

You may define new platforms, or edit existing platform definitions:

platforms: bogo: board: fakeduino:beep:bogo package: potato:salad gcc: features: - omit-frame-pointer # becomes -fomit-frame-pointer flag defines: - HAVE_THING # becomes -DHAVE_THING flag warnings: - no-implicit # becomes -Wno-implicit flag flags: - -foobar # becomes -foobar flag zero: ~ # undefines the `zero` board completely esp8266: # redefines the existing esp8266 board: esp8266:esp8266:booo package: esp8266:esp8266 gcc: features: defines: warnings: flags: 

For your example programs, you may set external libraries to be installed and included. You may also choose the platforms on which the compilation will be attempted:

compile: libraries: - "Adafruit FONA Library" platforms: - esp8266 

For your unit tests, in addition to setting specific libraries and platforms, you may filter the list of test files that are compiled and tested. This may help speed up targeted testing.

unittest: compilers: - g++ # default - g++-4.9 - g++-7 testfiles: select: - "*-*.*" reject: - "sam-squamsh.*" libraries: - "abc123" - "def456" platforms: - bogo 

More Documentation

This software is in alpha. But SampleProjects/DoSomething has a decent writeup and is a good bare-bones example of all the features.

Known Problems

Author

This gem was written by Ian Katz ([email protected]) in 2018. It's released under the Apache 2.0 license.

See Also