Ruby Practice Practicum - Currency Converter

Overview

In this practicum you will implement a currency converter: Given a from currency, an amount in that currency, and a to currency, you will provide the equivalent amount in the to currency. Input to the program consists of lines containing comma-separated values (CSV) of the form:

from_currency,amount,to_currency

where from_currency and to_currency are strings identifying the currencies to use (USD for U.S. dollars, CAN for Canadian dollars, EUR for Euros, AUD for Australian dollars, and GBP for Great Britain Pounds sterling and amount is the amount to be converted. For example:

EUR,50,HRK

converts 50 Euros to Kuna and

GPB,33.75,USD

converts 33.75 British pounds to U.S. dollars.

You may assume that all input lines are well-formed (have exactly 3 fields) and syntactically correct (the first and third fields are supported currency Strings and the second field is a String representing a number - use the to_f method on String to convert this to a numeric value).

Program Specification & Testing

You will first complete the three methods in currency_util.rb:

parse(line)

Parse the String line, containing a CSV line, into an String array using the String split method with a comma delimiter (pattern) and return this array. Note that this must work for any String with any number of fields.

to_dollars(currency,amount)

Convert the amount of the given currency to dollars. A hash, mapping each currency to the dollar conversion rate, is provided. Multiplying the amount by the appropriate rate gives the equivalent dollars. Use the round method in Float to round the result to 2 fractional digits.

from_dollars(currency,amount)

Convert the amount of dollars to the given currency. A hash, mapping each currency to the dollar conversion rate, is provided. Dividing the dollar amount by the appropriate rate gives the equivalent amount of the currency. Use the round method in Float to round the result to 2 fractional digits.

You must also test these three methods - see the test framework in currency_test.rb.

You must add at least one more test each for to_dollars and from_dollars; these tests must exercise behavior different from the ones provided. They do NOT need to be as thorough in testing all cases as are the provided tests.
You must add at least two distinct tests for parse testing two (2) different behaviors. Input lines that all have three fields consisting of two strings and a number are not different from a behavior point of view, even if the strings and numbers are different.

After completing the methods and unit testing them, you will complete the main "driver" program in currency.rb which provides for processing conversion requests from standard in and displaying results to standard out.

Instructions

Download the files linked to above into a new directory named Practicum-1 located at the root directory of your Git repository (not in a sub-directory!). For reference, here are links to the files again:

currency.rb - Contains the main "driver" program.
currency_util.rb - Contains the utility methods.
currency_test.rb - Ruby unit tests for the utility methods.

Your code should follow proper Ruby style guidelines (2 space indentation per level; 80 characters max. per line, etc.). You need not add any further documentation.

Submission

You only need to submit these files to your repository if required by your instructor.

The three files must be in directory Practicum-1 at the top of your Git repository.
You must add and commit and push your changes to have them show up in the repository.
We suggest adding. committing, and pushing after each significant addition or change to maximize potential credit.