String calculator using TDD | Team Cheese 🧀

String Calculator

class StringCalculator
    def self.add(numbers_string)
        invalid_input?(numbers_string) ? "Invalid Input" : add_all_numbers(numbers_string)
    end

    def self.invalid_input?(input_string)
        input_string.include?('-') || input_string.include?('.')
    end

    def self.add_all_numbers(numbers)
        numbers.split(/:|,/).reduce(0) {|sum,n| sum + n.to_i}
    end
end



//tests
require 'string_calculator'

describe StringCalculator do
    it "returns 0 for an empty string" do
        expect(StringCalculator.add("")).to eq(0)
    end
    
    it "returns 1 for '1'" do
        expect(StringCalculator.add("1")).to eq(1)
    end
    
    it "returns 2 for '1,1'" do 
        expect(StringCalculator.add("1,1")).to eq(2)
    end
    
    it "returns 10 for '10'" do
        expect(StringCalculator.add("10")).to eq(10)
    end
    
    it "returns 106 for '1,100,5' " do 
        expect(StringCalculator.add("1,100,5")).to eq(106)
    end
    
    it "returns 5 for '2:3'" do 
        expect(StringCalculator.add("2:3")).to eq(5)
    end

    it "returns 76 for '45:22,9'" do 
        expect(StringCalculator.add("45:22,9")).to eq(76)
    end
    
    it "returns 'Invalid Input' for '-1'" do
        expect(StringCalculator.add("-1")).to eq("Invalid Input")
    end

    it "returns 'Invalid Input' for '45:22,-9'" do 
        expect(StringCalculator.add("45:22,-9")).to eq("Invalid Input")
    end

    it "returns 'Invalid Input' for '12,5.5'" do 
        expect(StringCalculator.add("12,5.5")).to eq("Invalid Input")
    end
end