Coding Dojo at OrlandoPHP.org: Roman Numerals

main.php

<?php
/**
 * Given a decimal number like 1, 3 7, 13, 57, 42, convert to its Roman Numeral
 * equivalent. For example, "46" is "XLVI", "973" is "CMLXXIII", "1984" is
 * "MCMLXXXIV".
 */
function toRoman($decimal){
    $romanNumerals = array(
        "1"=>"I",
        "2"=>"II",
        "3" => "III",
        "4" => "IV",
        "5"=>"V",
        "10"=>"X",
        "50"=>"L",
        100 => 'C',
        500 => 'D',
        1000 => 'M',
    );

    #array_key_exists
    return @$romanNumerals[$decimal];

}

test.php

<?php

require_once 'main.php';

class Test extends PHPUnit_Framework_TestCase
{
    function test_something ( )
    {
        //$this->assertTrue(false, 'This will never work');

        //$this->assertEquals(true, false, 'Some message');

        //$this->assertFalse((boolean) 0);
    }

    // call function toRoman() with 46, assertEquals() "XLVI"
    /**
     * in   | out
     * 1    | I
     * 5    | V
     * 10   | X
     * 50   | L
     * 100  | C
     * 500  | D
     * 1000 | M
     * 2    | II
     * 3    | III
     * 4    | IV
     * 6    | VI
     * 7    | VII
     * 8    | VIII
     * 9    | IX
     * 20   | XX
     * 30   | XXX
     * 40   | XL
     * 46   | XLVI
     * 60   | LX
     * 70   | LXX
     * 80   | LXXX
     * 90   | XC
     * 200  | CC
     * 300  | CCC
     * 973  | CMLXXIII
     */

    function getRomanNumerals()
    {
        return array(
            array('I', 1),
            array('V', 5),
            array('X', 10),
            array('L', 50),
            array('C', 100),
            array('D', 500),
            array('M', 1000),
        );
    }

    /**
     * Check out "Data Providers" in the PHPUnit manual: http://j.mp/154sCgt
     *
     * @dataProvider getRomanNumerals
     */
    function test_toRoman($numeral, $decimal)
    {
        $this->assertEquals($numeral, toRoman($decimal), 'Input: ' . $decimal);
    }

    function test_toRomanReturnsIForOne()
    {
        $this->assertEquals('I', toRoman(1));
    }

    function test_toRomanReturnsVForFive()
    {
        $this->assertEquals('V', toRoman(5), 'Input of 5 should return V');
    }

    function test_toRomanReturnsXForTen()
    {
        $this->assertEquals('X', toRoman(10), 'Input 10 should return X');
    }

    function test_toRomanReturnsLForFifty()
    {
        $this->assertEquals('L', toRoman(50), 'Input 50 should return L');
    }

    function test_toRomanReturnsIIForTwo()
    {
        $this->assertEquals('II', toRoman(2), 'Input 2 should return II');
    }

    function test_toRomanReturnsIIIForThree()
    {
        $this->assertEquals('III', toRoman(3), 'Input 3 should return III');
    }

    function test_toRomanReturnsIVForFour()
    {
        $this->assertEquals('IV', toRoman(4), 'Input 4 should return IV');
    }
}