hw2.2-converters

Learning objectives

After completing the assignment, you should have gained experience with:

Writing tests
Debugging existing programs
The horrors of the imperial measurement system

Deliverables

A repo containing at least converter.rb and converter_test.rb

Requirements

Explorer Mode

There's an existing program, available for download here, or below:

`# A class to convert units of measurement
# To use: Converter.new(32).f_to_c == 0
class Converter

  attr_accessor :number

  def initialize(number)
    @number = number
  end

  def c_to_f
   # Multiply by 9, then divide by 5, then add 32
   # For instance, 12C == 53.6F
   ((number * 9)/5) + 32
  end

  def f_to_c
    # Deduct 32, then multiply by 5, then divide by 9
    # For instance, 23F == -5C
    ((number - 32) * 5)/9
  end

  def quarts_to_cups
    # Four cups in a quart
    # So, 2 quarts == 8 cups
    number * 4
  end

  def cups_to_quarts
    number / 4
  end

  def inches_to_feet
    number / 12
  end

  def feet_to_inches
    number * 12
  end

  def seconds_to_milliseconds
    # 1000 milliseconds per second
    number * 1000
  end

  def milliseconds_to_seconds
    number / 1000
  end

  def feet_to_miles
    # A mile is 5280 feet
    # So, 13200 feet == 2.5 miles
    number / 5280
  end

  def miles_to_feet
    number * 5280
  end

  def feet_to_meters
    # A meter is 3.28084 feet
    # So, A mile == 1609.344 meters (when rounded to three decimals)
    (number / 3.28084).round(3)
  end

  def meters_to_feet
    number * 3.28084
  end

  def ounce_to_gram
    # One ounce == 28.3495 grams
    number * 28.3495
  end

  def gram_to_ounce
    number / 28.3495
  end

end`

It has no tests, and you strongly suspect there are bugs lurking in this program.

So, let's write some tests.

Each method (other than the attr_accessor methods and initialize) should have at least one associated test in converter_test.rb
Those tests should pass. Of note: Some of these methods have bugs in them. If you run into one, fix it.

Adventure Mode

Write a converter method for days into years. Write the test(s) for this method first. For our purposes, a year is 365.25 days (leap days)
Write the opposite conversion, again while writing the tests first.
Write two other conversions of your choice.

Epic Mode

Use your now thoroughly tested class in a command line tool. Ask the user for a number and unit, then convert it to it's companion.
If a unit has more than one companion, ask the user which unit they'd like to convert it into.
Use the ruby-tty tools for the above