From: "David A. Black" <dblack@...>
Date: 2008-12-01T04:17:25+09:00
Subject: Re: How to reset constants in tests?

Hi --

On Mon, 1 Dec 2008, Ben Johnson wrote:

> I am writing tests for configuration options that make class level
> changes. Because they are class level, the changes get carried over to
> the next test. What would be the best way to accomplish "transactions"
> for ruby constants. Basically a way to rollback any class level changes
> that were made during the test.

The first thing that comes to mind is something like this (untested,
and you'd have to adapt it a lot anyway):

   def change_option(const_name, value, klass)
     old_value = klass.const_get(const_name)
     klass.const_set(const_name, value)
     yield
     klass.const_set(const_name, old_value)
   end

   def test_something
     change_option("OPTION", value, klass) do
       ...
     end
   end


David

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