This command was undocumented, only for autotools, and it is enough to do
`brew install foo -i` and then `./configure --help` in two steps.

* 4.3.3 is the latest on 10.7
* Give up if we don't know what the latest is (10.8 and beyond)

In 1.8, Pathname.find would work (and do nothing) if the
source path didn't exist. In 1.9 this throws an exception
instead, so check whether the file exists before trying.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Pathname is one of the basic building block classes in Homebrew, and as
such it is preferrable that `require`ing it does not drag in other
Homebrew code; thus avoiding circular dependency situations. Its
dependency on bottles.rb gave it an implicit dependency on formula.rb,
among other things.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Since methods were being called on it without verifying its type.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

0.9.2 includes the formula specs refactoring.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Tools like `brew create` need to create and manipulate SoftwareSpec
objects. It is useful to be able to do this directly, rather than by
proxy through the special methods that serve the main formula DSL.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Now that a URL, version, and the (for lack of a better term) "specs"
associated with said URL (e.g. the VCS revision, or a download strategy
hint) are neatly bundled up in a SoftwareSpec object, it doesn't make
sense to pass them individually to download strategy constructors. These
constructors now take only the formula name and a SoftwareSpec as
parameters.

This allows us to move mirror handling out out of Formula#fetch and into
the download strategies themselves. While doing so, we adjust the mirror
implementation a bit; mirrors now assume the same "specs" as their
owner's URL. They are still only useable by the CurlDownloadStrategy,
but this provides a basis for extending mirror support to other
strategies.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

testing_env already requires utils; set up the ARGV and ENV extensions
there as well.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

IO#popen is called for each call to Hardware.is_64_bit?; this becomes
costly when it is repeatedly invoked. Luckily it is an invariant, so we
can store it in a class variable.

False is a valid value for this method, so the usual ||= idiom is not
applicable.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

 - pkg-config no longer defaults to checking /usr/X11/lib/pkgconfig;
   instead this path is added via ENV.x11 or depends_on :x11. Formulae
   that expect X11 libs should be explicitly marked as depends_on :x11.
 - Remove warning about /usr/X11 as a symlink.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Some formulae ask for the x11 environment with ENV.libpng; mirror this
in the new dependency form.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Shortened the part about the CLT-only systems, because this message is
never shown to them.

Closes Homebrew/homebrew#13061.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Signed-off-by: Jack Nagel <jacknagel@gmail.com>