First cuke. No implementation.
Added steps file. All pending.
Implemented Given.
First pass at When. Broken: calculator doesn't exist yet.
First pass at calculator. Empty implementation. Test still broken.
Implemented double function. Test passes. Then section unimplemented still.
Installed expect.js. Implemented Then section. Broken: scope problem in test.
Fixed scope problem. Test fails: expected 4 to equal 2.
Fixed calc implementation. Test passes.
Wrench in the works: unimplemented steps.
Added steps for bad input. Broken: no err message.
Implementation fixed. Tests pass.
Added more tests.