testrocket: My entry to the CodeBrawl.com "Ruby testing libraries" contest

README

TestRocket is a simple, tiny testing library for Ruby 1.9.

If => in a hash is a "hash rocket", then +-> and --> for tests should be
"test rockets"!

Simple syntax:

+-> { block that should succeed }
--> { block that should fail }

These tests would both pass:

+-> { 2 == 2 }
--> { 10 / 0 }

See the demonstration test "suite" for more.

Unique features (I hope):

* Unary plus/minus to denote expectations.
* Ability to fit the entire library into a single tweet/single line.

testrocket.rb

# A SINGLE FILE CONTAINING THE TEST LIBRARY
# A CLASS TO TEST, AND THE TESTS THEMSELVES

# ===========================================================
# TESTROCKET TESTING LIBRARY
module TestRocket
  def _test(a, b)
    send((call rescue()) ? a : b)
  end

  def +@; puts _test :_pass, :_fail; end
  def -@; puts _test :_fail, :_pass; end

  def _pass; '   OK'; end
  def _fail; " FAIL @ #{source_location.join(':')}"; end
end

Proc.send :include, TestRocket

# A functionally equivalent single liner. I figured you'd rather be able to read the code and output though.
# class Proc;def _t;call rescue();end;def +@;p _t ? '.' : _f; end;def -@; p _t ? _f : '.'; end;def _f; "F "+to_s;end;end




# ===========================================================
# "DIE" - Simple dice simulator for us to test
class Die
  attr_reader :sides
  
  def initialize(sides = 6)
    raise ArgumentError if sides < 2
    @sides = sides
  end  
  
  def roll
    rand(@sides) + 1
  end
end




# ===========================================================
# EXAMPLE TEST "SUITE" FOR "DIE"
#
# USAGE
# +-> { block that should succeed }
# --> { block that should fail }

+-> { Die.new(2) }
--> { Die.new(1) }
+-> { (1..6) === Die.new(6).roll }
+-> { Die.new.sides == 6 }

+-> { die = Die.new(6)
      1000.times { raise unless (1..6) === die.roll } }

+-> { die = Die.new(6)
      1000.times { raise if die.roll.zero? } }

# These two tests will deliberately fail
+-> { raise }
--> { true }

Awesome!

I like this approach and extended this test suite a litte bit (with "description" and "pending" operators).

Woah, I haven't seen the @ part of the method definition before. What's the deal with it? Does it only work for Procs?
Would someone be so kind as to point me to the documentation for it? It's one of those things that's hard to Google...

@peterbrowne I haven't seen it before also. Some googling led me to know it's overloading the unary method definition.

It means you can to things like

class String
    def !@
      "!! " << self << " !!"
    end
end
! "Hello World" # output =>  "!! Hello World !!"

The @ is for the (four) unary operators, which can be overloaded.

Maybe we should read !@ like "operator in front of object", wrote another example code for showing differences.