How to write codes for TDD

Rails
1

Hi all,
I am a newbie in rails. I have done some small applications in
rails but can’t know how to make TDD and BDD in RSpec and other
tools. I have tried by reading the rpesc tutorial from rspec.info
website, But can’t understand where to start coding and run for Red,
Green behaviour of code. Please help,

Thanks
deb

2

On Jul 27, 11:59 am, debadatta [email protected] wrote:

Hi all,
I am a newbie in rails. I have done some small applications in
rails but can’t know how to make TDD and BDD in RSpec and other
tools. I have tried by reading the rpesc tutorial from rspec.info
website, But can’t understand where to start coding and run for Red,
Green behaviour of code. Please help,

The theory is quite simple: instead of writing some code and then a
test to exercise, write a test first (that sets out what you are
trying to achieve) and then write the code for it. That flip in
mindset is somewhat independent to the actual tool use use to write
your tests (although some encourage it more than others)

Fred

3

Thanks
deb

The Ruby-on-Rails tutorial book (http://railstutorial.org/) is a good
starting point. See section Mostly static pages/Our first tests.

Adrian

4

Buy “The RSpec Book” from Pragmatic. It’s outstanding, and will give you
extremely useful insight on TDD and BDD.

Cheers!!

5

Juan P. Genovese wrote:

Buy “The RSpec Book” from Pragmatic. It’s outstanding, and will give you
extremely useful insight on TDD and BDD.

Take this really simple example of a spec (test) from “The RSpec Book.”

greeter_spec.rb

describe “RSpec Greeter” do
it “should say ‘Hello RSpec!’ when it receives the greet() message” do
greeter = RSpecGreeter.new
greeting = greeter.greet
greeting.should == “Hello RSpec!”
end
end

Now run that file with:

spec greeter_spec.rb

Obviously it will fail. There is no code to implement RSpecGreeter
class. You now have a successful failure. Failure is what you expected
at this point.

You are now at “Red.”

You’re next goal is to get to “Green.” You do that by implementing just
enough code to make the above spec pass. This involves creating the
RSpecGreeter class and implementing a “greet” method that returns the
string “Hello RSpec!” This is exactly what the spec says to implement.
Nothing more, nothing less.

Now run the spec again, which should now pass. You are at “Green.”

Next step is “Refactor.” This is your opportunity to review the code you
wrote and clean it up by removing duplication, improving formatting,
etc. You can now do that refactoring with confidence because you have
the spec that will tell you if you’ve broken anything, according to the
specified requirement.

The next step in the process is to get back to “Red” by writing another
spec (or test).

This is a basic BDD cycle. Keep repeating this cycle until you can’t
think of any more specs to write. At that point you should have
something to release (or at least be able to complete a feature story).