FakeI2CBusDriver.java

package frc.robot.utilities;

import edu.wpi.first.wpilibj.I2C;

public class FakeI2CBus extends I2C {

    public FakeI2CBus(int address) {
        super(I2C.Port.kOnboard, address);
    }

    public byte[] readOnly() {
        byte[] buffer = new byte[16];
        for (int i = 0; i < buffer.length; i++) {
            if (i%2 != 0) {
                buffer[i] = 2;
            }
        }

        buffer[0] = 15;
        buffer[2] = 14;
        buffer[4] = 16;
        buffer[6] = 25;
        buffer[8] = 26;
        buffer[10] = 17;
        buffer[12] = 16;
        buffer[14] = 15;
        buffer[16] = 14;

        return buffer;
    }

}

LineFollowerSensorTest.java

package frc.robot.sensors;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertTrue;

import org.junit.Test;

import frc.robot.sensors.LineFollowerSensorArray;
import frc.robot.utilities.*;

public class LineFollowerSensorTest {
    FakeI2CBus i2cBus = new FakeI2CBus(9);
    LineFollowerSensorArray lfs = new LineFollowerSensorArray(i2cBus);

    @Test
    public void isThereLineTest() {
        boolean boolBufTest[] = new boolean[8];
        // Set data
        boolBufTest[0] = false;
        boolBufTest[1] = false;
        boolBufTest[2] = false;
        boolBufTest[3] = true;
        boolBufTest[4] = true;
        boolBufTest[5] = false;
        boolBufTest[6] = false;
        boolBufTest[7] = false;
        boolBufTest[8] = false;

        boolean[] boolBuf = lfs.isThereLine();
        assertArrayEquals(boolBufTest, boolBuf);
    }

    @Test
    public void getSensorReadingTest() {
        /*
        Needs to:
        - pass dummy i2c device
        - have dummy i2c device return predefined data
        - Make sure math works
        */
        System.out.println(lfs.getSensorReading().lineFound);
        assertTrue(lfs.getSensorReading().lineFound);    
    }
}