Kata's

Description

A project containing Kata`s for practicing TDD using Kotlin. Each kata has its own package, and each exercise goals are described below.

1. String Calculator

package name: string

1. An empty string returns zero
2. A single number returns the value
3. Two numbers, comma delimited, returns the sum
4. Two numbers, new line delimited, returns the sum
5. Three numbers, delimited either way, returns the sum
6. Negative numbers throw an exception
7. Numbers greater then 1000 are ignored

2. Password Verifier

package name: password

1. Password should be larger than 8 chars
2. Password should have one uppercase letter at least
3. Password should have one lowercase letter at least
4. Password should have one number at least
5. Each one of these should throw an exception with a different message of your choosing
6. Password is OK if the previous conditions are satisfied

3. Greeter

package name greet

1. Should return greeting for given name:
   input "name"
   output Hello, name.
2. Should return generic greeting when no or empty name provided:
   input "" or null
   output Hello, my fiend
3. Should return shouting greeting when shouting name provided:
   input "NAME"
   output HELLO NAME!
4. Should return greeting for both when two names provided:
   input "name1", "name2"
   output Hello, name1 and name2.
5. Should return greeting for all when more than two names provided:
   input "name1", "name2", "name3"
   output Hello, name1, name2 and name3.
6. Should return greeting when mixing shouting names with normal names:
   input "name1", "NAME2", "name3"
   output Hello, name1 and name3. AND HELLO NAME2!
7. Should return greeting when coma separated names provided as input:
   input "name1", "name2, name3"
   output Hello, name1, name2, and name3.

4. FizzBuzz

package name fizzbuzz

1. Should print numbers from 1 to 100
2. For the multiples of 3 print Fizz instead of the number
3. For the multiples of 5 print Buzz instead of the number
4. For the multiples of both 3 and 5 print FizzBuzz instead of the number
5. A number is Fizz if it is dividable by 3 or if it contains 3 inside
6. A number is Buzz if it is dividable by 5 or if it contains 5 inside

5. Roman to decimal numbers

package name roman

Converter to resolve input from Roman numerals into decimal. The values of the roman numerals are shown in the following table.

Symbol	Value
I	1
V	5
X	10
L	50
C	100
D	500
M	100

Numbers are formed by combining symbols together and adding the values. Generally, symbols are placed in order of value, starting with the largest values. When smaller values precede larger values, the smaller values are subtracted from the larger values, and the result is added to the total:

Roman Number	Computation	Value	Comment
IV	5 - 1	4	only subtraction
VI	5 + 1	6	only addition
MMVI	1000 + 1000 + 5 + 1	2006	only addition
MCMXLIV	1000 + (1000 - 100) + (50 - 10) + (5 - 1)	1944	addition and subtraction

6. Banking Kata

package name banking

Simple bank application with the following features

- Deposit into Account
- Withdraw from an Account
- Print the Account statement to the console

Statement should have transactions in the following format:

DATE       | AMOUNT  | BALANCE
10/04/2014 | 500.00  | 1400.00
02/04/2014 | -100.00 | 900.00
01/04/2014 | 1000.00 | 1000.00

Constraints:

1. Start with a class with the following structure

   public class Account {
   
     public void deposit(int amount)
   
     public void withdraw(int amount)
   
     public void printStatement()
   }
   

2. You are not allowed to add any other public methods in this class

3. Use Strings and Integers for dates and amounts (keep it simple)

4. Don't worry about the spacing in the statement printed in the console

6. Point of sale Kata

package name sales

Simple app for scanning bar codes to sell products

Stage 1 - Sell one item

Scanning a barcode should display its price

- Barcode '12345' should display price '$7.25'
- Barcode '23456' should display price '$12.50'
- Barcode '99999' should display 'Error: barcode not found'
- Empty barcode should display 'Error: empty barcode'

Stage 2 - Sell multiple items

- Introduce a concept of scanning multiple items
- Introduce a concept of `total` command that would display the sum of the scanned products

7. Refactoring legacy code

package name legacy

Legacy code that has to be improved. We have to make the code better while making sure we preserve the same behaviour. The idea is to cover the legacy code with tests to make sure we won't break its functionality, and once we are confident we can start refactoring, use as much as possible automated refactoring and minimise the manual refactoring for extra safety.