New Formula: Tup

Tup is a build tool that fills a role similar to make---except much more
efficient for large source trees.

Closes Homebrew/homebrew#7636.

Signed-off-by: Charlie Sharpsteen <source@sharpsteen.net>

Formula/tup.rb

@@ -0,0 +1,34 @@
+require 'formula'
+
+class Tup < Formula
+  homepage 'http://gittup.org/tup/'
+  head 'https://github.com/gittup/tup.git'
+  url 'https://github.com/gittup/tup.git', :tag => 'v0.4.1'
+  version '0.4.1'
+
+  depends_on 'pkg-config' => :build
+  depends_on 'fuse4x'
+
+  def install
+    if `kextfind -b org.fuse4x.kext.fuse4x`.chomp.empty?
+      onoe <<-EOS.undent
+        Tup requires the fuse4x kernel extension to be loadable in order to
+        build. Pleas follow the directions givein by `brew info fuse4x-kext`
+        and try again!
+      EOS
+      exit 1
+    end
+
+    # Tup hard-wires CC to clang on OS X.
+    inreplace ['bootstrap.sh', 'macosx.tup'], /^([ \t]*CC[ \t]*=[ \t]*).*$/, "\\1#{ENV.cc}"
+    inreplace 'Tupfile', '`git describe`', version
+
+    system "./bootstrap.sh"
+    bin.install 'tup'
+    man1.install 'tup.1'
+  end
+
+  def test
+    system "tup -v"
+  end
+end