jwmerrill@gmail.com
6/6/2007 5:07:00 AM
If I wanted to show them how eXtreme I was, I would start by writing
some tests:
-----
# fizzbuzz_test.rb
require 'spec'
require 'fizzbuzz'
describe :fizzbuzz do
# This is just so we can read the results of all those 'puts'
before do
@output = StringIO.new()
$stdout = @output
fizzbuzz()
@output.rewind
@lines = @output.readlines.map {|str| str.chop}
end
after do
$stdout = STDOUT
end
it "should print 1 as the first line" do
@lines[0].to_i.should == 1
end
end
-----
Then we make it pass
-----
# fizzbuzz.rb
def fizzbuzz()
puts 1
end
if __FILE__ == $0
fizzbuzz()
end
-----
Add another test
-----
# fizzbuzz_test.rb
it "should have 100 lines" do
@lines.size.should == 100
end
-----
Make it pass
-----
# fizzbuzz.rb
def fizzbuzz()
(1..100).each do |num|
puts num
end
end
-----
Keep the rhythm going
-----
# fizzbuzz_test.rb
it "should print 'Fizz' as the third line" do
@lines[2].should == 'Fizz'
end
-----
# fizzbuzz.rb
def fizzbuzz()
(1..100).each do |num|
if num % 3 == 0
puts 'Fizz'
else
puts num
end
end
end
-----
# fizzbuzz_test.rb
it "should print 'Buzz' as the fifth line" do
@lines[4].should == 'Buzz'
end
-----
# fizzbuzz.rb
def fizzbuzz()
if num % 3 == 0
puts 'Fizz'
elsif num % 5 == 0
puts 'Buzz'
else
puts num
end
end
end
-----
# fizzbuzz_test.rb
it "should print 'FizzBuzz' as the fifteenth line" do
@lines[14].should == 'FizzBuzz'
end
-----
# fizzbuzz.rb
def fizzbuzz()
(1..100).each do |num|
if num % 15 == 0
puts 'FizzBuzz'
elsif num % 3 == 0
puts 'Fizz'
elsif num % 5 == 0
puts 'Buzz'
else
puts num
end
end
end
-----
And one more for good measure:
-----
# fizzbuzz_test.rb
it "should print 'Buzz' as the last line" do
@lines.last.should == 'Buzz'
end
-----
The final results are
-----
# fizzbuzz.rb
def fizzbuzz()
(1..100).each do |num|
if num % 15 == 0
puts 'FizzBuzz'
elsif num % 3 == 0
puts 'Fizz'
elsif num % 5 == 0
puts 'Buzz'
else
puts num
end
end
end
if __FILE__ == $0
fizzbuzz()
end
-----
# fizzbuzz_test.rb
require 'spec'
require 'fizzbuzz'
describe :fizzbuzz do
# This is just so we can read the results of all those 'puts'
before do
@output = StringIO.new()
$stdout = @output
fizzbuzz()
@output.rewind
@lines = @output.readlines.map {|str| str.chomp}
end
after do
$stdout = STDOUT
end
it "should print 1 as the first line" do
@lines[0].to_i.should == 1
end
it "should print 100 lines" do
@lines.size.should == 100
end
it "should print 'Fizz' as the third line" do
@lines[2].should == 'Fizz'
end
it "should print 'Buzz' as the fifth line" do
@lines[4].should == 'Buzz'
end
it "should print 'FizzBuzz' as the fifteenth line" do
@lines[14].should == 'FizzBuzz'
end
it "should print 'Buzz' as the last line" do
@lines.last.should == 'Buzz'
end
end
-----
Now before pulling such a stunt, I might ask plainly if they were
looking for a trivial solution to a trivial problem, in which case I
would immediately write down the final answer, or if they wanted me to
suspend disbelief and imagine this is a part of a large and important
system rather than a one off game, in which case I might do the
previous. After all, who wants to work for people that make you guess
what they want?
Jason Merrill