All entries for Monday 12 June 2006

BDD Meta–programming

I'm working on a Boo macro library for Rhino Mocks . I'm "dog-fooding" my Specter behaviour driven development framework in the process.
I have to be able to specify how a macro should expand into real code. The spec code is now looking like this:

specify "x as int arg is sent as 0":
  check(
    ast { disallow foo.Bar(x as int) },
    ast { foo.Bar(0); Rhino.Mocks.LastCall.Repeat.Never() }
  )

I'm loving how flexible the Boo language is. It's hard to believe that the code is still Boo!

"check" is a function that expands the first argument using the macro being spec'd and makes sure it matches the second argument. (check is actual a partial application of a general check function that takes the macro first)

check = { input as MacroStatement, expected as Node | CheckMacro(macro, input, expected) }

def CheckMacro(macro as AbstractAstMacro, input as MacroStatement, expected as Node):
    m = Method()
    m.Body.Add(input)
    NUnit.Framework.Assert.AreEqual(
        expected.ToCodeString().Trim(),
        macro.Expand(input).ToCodeString().Trim()
    )

: 12 Jun 2006 22:35 |  Tags: Bdd Boo Coding Dotnet |  Comments (0) |  Close comments |  Report a problem