By always passing around a single, unnested array rather than splatting
and then defensively flattening and compacting things, we can avoid
allocating a bunch of unnecessary arrays. This gives a performance boost
of roughly 4% when enumerating 2500 formulae, and has the side effect of
cleaning up the dependency API.
These tests document the relative precedence of the stable, bottle,
devel, and head specifications, and the conditions that can influence
which is selected (e.g. command-line flags).
The initializer for Formula does a number of validations, but it does
them in a weird order, and some attributes aren't validated under
certain circumstances. This became even more of a mess when most
software package attributes were moved into the SoftwareSpec class.
This commit removes the last vestiges of storing these attributes as
instance variables. In particular, it eliminates #set_instance_variable
and #validate_variable, replacing them with methods that operate on
SoftwareSpec instances, and generate more useful errors.
Doing these validations unconditionally in the initializer means we bail
out much earlier if the formula has invalid attributes or is not fully
specified, and no longer need to validate in #prefix.
Technically we don't need to validate in #brew either, but we continue
to do so anyway as a safety measure, and because we cannot enforce calls
to super in subclasses.
Build 211 can build most things, but I've seen intermittent
miscompilation and slower code. Also it comes from Xcode 4.2, so most
people don't have it anyway. Let's use 218 as the minimum viable
version.
This was meant to support:
env do |req|
append_path 'PATH', req.some_method
...
end
i.e., the block was evaluated in the context of ENV. But it turned out
to be not so useful after all, so I'm ripping it out before something
actually depends on it.
