What happens when objects implement == incorrectly

output.txt

$ rspec example_spec.rb 
F

Failures:

  1) Pessimist never thinks its equal, even to itself
     Failure/Error: pessimist.should eq(pessimist)
       
       expected: #<Pessimist:0x007fb82a9bae80>
            got: #<Pessimist:0x007fb82a9bae80>
       
       (compared using ==)
       
       Diff:
     # ./example_spec.rb:10:in `block (2 levels) in <top (required)>'

Finished in 0.00143 seconds
1 example, 1 failure

pessamist_spec.rb

class Pessimist
  def ==(other)
    false
  end
end

describe Pessimist do
  it "never thinks its equal, even to itself" do
    pessimist = Pessimist.new
    pessimist.should eq(pessimist)
  end
end

@lucapette - thanks - I had seen that locally too but I guess I copied it to the gist before I fixed it :)