[Zope3-dev] zc.buildout: When is recipe.install run?

[Daniel Nouri]

While using buildout in our recent project[1] we have discovered that 
some recipe's `install` method is being run although neither the recipe 
nor the configuration has changed.

 From reading the documentation I got the impression that whenever 
`install` is called, the parts directory (i.e. whatever I returned on 
last `install`) should have been cleaned up.

However in our case, the `openoffice` recipe is seemingly been run 
although there haven't been any changes to the recipe or configuration. 
  Further, the parts directory of the recipe is still in place when 
`install` is run.

What can a recipe assume in `install`?  And could the fact that I'm 
using `develop` in `[buildout]` trigger the install on each run?  And 
shouldn't the parts directory be cleaned up everytime I am run?

I was thinking that an `update` method would be useful for recipes to 
check if they need to do something even if recipe and configuration are 
the same.  Any recipe that checks out from SVN would be using that 
update method.

Daniel


[1] https://infrae.com/svn/buildout/oooconv-dev/trunk/buildout.cfg