Dump original implementation.
Add test specification boilerplate.
Add specifications for valid sides.
Add specifications for invalid sides.
Implement minimum required code to make  context test fail.
Implemented minimum required code to make  context fail.
Fix name error in negativity or zero test.
Add private Triangle class interface.
Add missing Triangle#scalene? method.
Implement minimum required code to make equitalateral test pass.
Remove Triangle#scalene? method as not needed.
Add minimum required code to make isosceles test pass.
Add minimum required code to make scalene test pass.
Add minimum required code to make invalid side value test pass.
Add minimum required code to make violates inequality test pass.
Implement minimum required code to make negative or zero length side test pass.