Memoize .helpers

[dqminh]

In one of my apps, I have some specs that expect .helpers to be consistent for the same instance of presenter. However, it seems that Draper instantiates new instance of HelpersWrapper everytime helpers is accessed

This does not create new instance of HelpersWrapper every time ".helpers" is accessed

[steveklabnik]

So, this can be dangerous. The reason is that the context can change, like when you enter into a do block in a helper.

I guess that we are memozing the wrapper, and not Rails' context. Hm.

[haines]

Memoizing the wrapper will memoize the context because we pass it in and store it in an instance variable in the wrapper.

[steveklabnik]

Hmmm yeah. So I'm not sure this won't break stuff. That integration suite and app would be useful now...

[dqminh]

Hmm, I thought that draper is also performing memoization of the view context with Thread.current. Is it susceptible to view_context change as well ?

[steveklabnik]

Wellllllllll maybe. I'm not sure. See #124 for the weirdness.

I'm actually planning on re-writing the entire view context code later today. I had some discussions with @wycats about it, and we can do much better.

I'm gonna merge this for now, and we'll see if it breaks things.