Conventional Debugging vs. TDD

Conventional Debugging vs. TDD

Conventional 

• Write 10s of lines, run, hit bug: break out debugger
• Insert printfʼs to print variables while running repeatedly
• Stop in debugger, tweak/set variables to control code path
• Dammit, I thought for sure I fixed it, now have to do this all again

TDD

• Write a few lines, with test first; know immediately if broken
• Test short pieces of code using expectations
• Use mocks and stubs to control code path
• Re-run test automatically