numeric?

test_numeric.rb

require 'minitest'
require 'minitest/autorun'
require 'minitest/pride'


class TestNumeric < Minitest::Test
	def numeric?(arg)
		!/\A[+-]?\d+\z/.match(arg.to_s).nil?
	end


	def test_int
		(1..1_000_000).each do |i|
			assert numeric?(i)
			assert numeric?("+#{i}")
			assert numeric?("-#{i}")
		end
	end


	def test_float
		refute numeric?(1.2)
		refute numeric?(12.2)
		refute numeric?(1.32)
		refute numeric?('15.2')
		refute numeric?(131.12)
		refute numeric?(12_222_222_222_222.21232)
		refute numeric?(111.2331)
	end


	def test_string
		assert numeric?('0')
		assert numeric?('1')
		assert numeric?('121234')
	end


	def test_special_cases
		actual = numeric?('/jobs/12g34/new/')
		refute actual
		assert_kind_of FalseClass, actual
	end


	def test_with_sign
		assert numeric?(-12)
		assert numeric?(12)
		assert numeric?(+12)
	end
end