Alex Y. wrote:
Allow me to shamelessly copy and paste from an old post of mine:
$ cat testable.rb
module Test; module Unit; class TestCase; end; end; end
module Testable
def test_case(&block)
Class.new(Test::Unit::TestCase).module_eval &block
end
end
$ cat builtin_tests.rb
require ‘testable’
class MyWorkingClass
extend Testable
def foo(a,b)
return a+b
end
test_case {
def test_foo_null
assert_equal 2, MyWorkingClass.new.foo(1,1)
end
}
end
if FILE == $0
puts MyWorkingClass.new.foo(1,1)
end
$ ruby builtin_tests.rb
2
$ testrb builtin_tests.rb
Loaded suite builtin_tests.rb
Started
.
Finished in 0.00095 seconds.
1 tests, 1 assertions, 0 failures, 0 errors
$
Something like that?
No, the whole approach is different. I’d say the movies I linked to can
explain it far better than I can.
With DBC, if contracts are enabled (in Eiffel you can disable contracts
to get better performance), your method is tested everytime you call the
method. It tests pre-conditions and/or post-conditions (providing you
the old state for your post-conditions). Also after every call to a
method the class invariant is tested to validate your object. That’s the
basic idea.
One way that could probably be implemented (though, only as of ruby 1.9
due to &block params) might look this:
class DayOfTime
extend DBC
invariant {
@hour.between?(0,23)
@min.between?(0,59)
@sec.between?(0,59)
}
define(:min=) {
pre_condition { |value|
value.kind_of?(Numeric)
value.between?(0,59)
}
body { |value|
@value = value
}
post_condition { |old, value|
@hour == old.hour
@min == value
@sec == old.second
}
}
end
Regards
Stefan
