cheat sheets.

== Implemented assertions

* should.<predicate> and should.be.<predicate>
* should.equal
* should.match
* should.be.identical_to / should.be.same_as
* should.raise(*exceptions) { }
* should.change { }
* should.throw(symbol) { }
* should.satisfy { |object| }


== Added core predicates

* Object#true?
* Object#false?
* Proc#change?
* Proc#raise?
* Proc#throw?
* Numeric#close?

== before/after

before and after need to be defined before the first specification in
a context and are run before and after each specification.

  describe 'A new array' do
    before do
      @ary = Array.new
    end
    # ...
  end

== Shared contexts

  shared "an empty container" do
    it "should have size zero" do
    end

    it "should be empty" do
    end
  end

  context "A new array" do
    behaves_like "an empty container"
  end

These contexts are not executed on their own, but can be included with
behaves_like in other contexts.  You can use shared contexts to
structure suites with many recurring specifications.

== Matchers

  def shorter_than(max_size)
    lambda { |obj| obj.size < max_size }
  end

  [1,2,3].should.be shorter_than(5)

You can use modules and extend to group matchers for use in multiple
contexts.