A proposed refactoring, relevant to ruby, lisp-like languages, python (?), and could be badly emulated in PHP.  Name probably needs to be adjusted (to ExecuteAroundPattern from KentBeck's SmalltalkBestPracticePatterns).  Thoughts?

Replace:

	def test_thing_creates_record
	  before_count = record_count('foo')
	  thing
	  assert_equal before_count + 1, record_count('foo')
	end

With:

	def assert_creates_record_in_foo
	  before_count = record_count('foo')
	  yield
	  assert_equal before_count + 1, record_count('foo')
	end

	def test_thing_creates_record
	  assert_creates_record_in_foo do
	    thing
	  end
	end

See also AssertYinYang

''I think a rationale and explanation would be helpful, but perhaps I'm showing my lack of Ruby knowledge.  Is it obvious to Ruby programmers?'' -- DaveVoorhis

It's obvious to a non-Ruby programmer having been exposed to Smalltalk, Lisp and Ruby. All you need to know is 'yield' means 'call functor'. This is P''''''arameterizedExtractMethod, or something along those lines. Or maybe E''''''xtractAllButMethod/E''''''xtractFrame.

''Ah hah!  In my mind 'yield' was evocative of the Java platform's Thread.yield(), and confusion ensued.  Note to self: IwannaLearnRuby.'' -- DV

To me it was more evocative of 'yield' in the coroutine sense, probably because I didn't see any thread goo in the area.  CeeSharp has added a yield keyword to facilitate writing iterators as some sort of half-ass coroutines, transforming the iterator's frame into a heap-allocated object. -- JH

Motivations to do so, off the top of my head (and I've just done this on a real live project, so some of these are real):

* SelfDocumentingCode - especially if the wrapping code is heavy, this is much easier to read.
* You can then PullUpMethod
* OnceAndOnlyOnce - if you have multiple different "things" that you want to assert create a record in foo.

Hmm, refactoring example was doing proposed refactoring ''and'' AddParameter.  Now fixed.

----

The really good news is intensive research, involving hundreds of programmer-years, has not yet found a way to abuse blocks in RubyLanguage. If you are writing a method, and you don't know what to write next, you just write ''yield'', and let the calling code figure it out.

Furtherless, ExecuteAroundPattern is a much, much better idiom for ResourceAcquisitionIsInitialization than destructors OR ''finally'' blocks. You just put the ''finally'' or ''ensure'' after the ''yield''. --PhlIp

----

ExtractFrame is the best so far, I think, but not quite accurate.   ExtractDonut?

''Is this just a variation on ExtractMethod where the method gets a parameter that just happens to be a code block?  You could do basically the same thing in a lot of languages by passing a lambda / function pointer / subroutine reference / etc to the new function.''