I ran this solution against my test suite and some tests failed.

I pointed out some of those cases in the "Discussion" section.

For example, for "1000" I think it outputs "ten hundred" instead of "one thousand". For "20", I think it displays "twenty zero". etc.

Let me know if I'm mistaken :)

Hi guys, I was intrigued by the top solution and then I decided to run it against my tests and some tests failed.

I think this kata should contain more tests (sorry, I never suggested something to a kata, I don't know how to do this)

But here are some that failed (I can probably send my whole suite if you are interested)

Test.assert_equals(int_to_english(1000), 'one thousand')

Test.assert_equals(int_to_english(100), 'one hundred')

Test.assert_equals(int_to_english(30), 'thirty')

Test.assert_equals(int_to_english(20), 'twenty')

Test.assert_equals(int_to_english(14), 'fourteen')

p1 == p2 should be p1.equals(p2)
http://stackoverflow.com/a/513839/2277505
Tests are passing but if input was read from IO, this would break.