I'm interested about using 2 different classes in 2 different environment. Both classes should share the same structure (methods), but the one used in production would be "light", with less verifications or less funtionnality or different actions.
Example: a SQL query class which doesn't check the type/existence of fields. Other example: a error handling class who logs and doesn't display messages.
I presume a specific design pattern already exists, but I don't really know which one I should digg into.
This may just be me...but that's a really bad idea.
You shouldn't have code running in live that you're not running in Development/Test. Otherwise, there's no way to verify that the code is working properly (other than, of course, pushing it in to production and crossing your fingers).
For that reason, I don't think you're going to find a good example of what you're looking for.
Update
What you described is slightly different than how your original question reads. If that's the case, you can have your 'framework' read for a configuration file that specifies validation and logging levels. That way, your configuration file can differ between environments and still be running the same code base.