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royosherove/string_calculator_test_unit1.rb

Created October 11, 2012 13:34
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simplest string calculator with test_unit and ruby
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string_calculator_test_unit1.rb
require "test/unit"
class StringCalculator
NEGATIVES_MSG = "negatives not allowed"
START_OF_CUSTOMDELIM_INDEX = 3
TOO_LARGE = 1001
def add(numbers)
cleaned = clean(numbers)
unless cleaned.include?(",")
return handle_single_number(cleaned)
end
cleaned = replace_delimters(cleaned)
actual = turn_into_actual_numbers(cleaned)
disallow_negatives(actual)
good_numbers = filter_allowable_numbers(actual)
return good_numbers.inject(&:+)
end
def clean(numbers)
numbers.strip.gsub("\n", ",")
end
def replace_delimters(numbers)
return numbers unless numbers.include?("//")
endindex = numbers.index(",")
delims = numbers[START_OF_CUSTOMDELIM_INDEX..endindex].delete("[").split("]")
delims.each do |delim|
numbers = numbers.gsub!(delim,",")
end
delim_char = numbers[2].chr
return numbers.gsub(delim_char,",")
end
def handle_single_number(number)
raise "#{NEGATIVES_MSG} #{number}" if number.include?("-")
return number.to_i
end
def turn_into_actual_numbers(numbers)
numbers.split(',').map(&:to_i)
end
def disallow_negatives(numbers)
negatives= numbers.find_all do |number|
number<0
end
raise "#{NEGATIVES_MSG} #{negatives}" unless negatives.empty?
end
def filter_allowable_numbers(numbers)
numbers.find_all do |number|
number < TOO_LARGE
end
end
end
class StringCalculatorTests < Test::Unit::TestCase
def calc
StringCalculator.new
end
def test_add_emptystring_zero
result = calc.add("")
assert_equal 0,result
end
def test_add_singlenumber_returnsThatNumber
result = calc.add("1")
assert_equal 1,result
end
def test_add_singlenumber_returnsThatNumber_1
result = calc.add("2")
assert_equal 2,result
end
def test_add_twonumbers_sumsThem
result = calc.add("1,2")
assert_equal 3,result
end
def test_add_twonumbers_sumsThem1
result = calc.add("1,3")
assert_equal 4,result
end
def test_add_twolargernumbers_sumsThem1
result = calc.add("10,30")
assert_equal 40,result
end
def test_add_newline_zero
result = calc.add("\n")
assert_equal 0,result
end
def test_add_newlinebetweennumbers_treatsasseperator
result = calc.add("1\n2")
assert_equal 3,result
end
def test_add_differentDelimiter_usedToParseTheSum
result = calc.add("//A\n1A2")
assert_equal 3,result
end
def test_add_differentDelimiter_usedToParseTheSum2
result = calc.add("//B\n1B2")
assert_equal 3,result
end
def test_add_neagative_throws
ex = assert_raise RuntimeError do
calc.add("-1")
end
assert_match /negatives not/, ex.message
end
def test_add_multiple_neagative_throws
ex = assert_raise RuntimeError do
calc.add("-1,-2")
end
assert_match /-1/, ex.message
assert_match /-2/, ex.message
end
def test_add_negativeandpositive_throwsonlythenegative
ex = assert_raise RuntimeError do
calc.add("-1,2")
end
assert_match /-1/, ex.message
assert_no_match /2/, ex.message
end
def test_add_numbersbiggerthan1000_ignored
result= calc.add("2,1001")
assert_equal 2,result
end
def test_add_delimiterslongerthanonechar_stillaccepted
result= calc.add("//AAA\n1AAA2AAA3")
assert_equal 6,result
end
def test_add_multipledelimiters_allused
result= calc.add("//[A][b]\n1A2b3")
assert_equal 6,result
end
def test_add_multipledelimiters_allused2
result= calc.add("//[AB][bc]\n1AB2bc3")
assert_equal 6,result
end
end
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