carthage 0.3.1 (new formula)

Closes Homebrew/homebrew#34807.

Formula/carthage.rb

@@ -0,0 +1,26 @@
+require "formula"
+
+class Carthage < Formula
+  homepage "https://github.com/Carthage/Carthage"
+  url "https://github.com/Carthage/Carthage.git", :tag => "0.3.1",
+                                                  :shallow => false
+  head "https://github.com/Carthage/Carthage.git", :shallow => false
+
+  depends_on :xcode => ["6.1.1", :build]
+
+  def install
+    # Carthage likes to do stuff with submodules itself so we need a "real"
+    # git clone rather than letting it play with our cache.
+    cp_r cached_download/".git", "."
+
+    system "make", "prefix_install", "PREFIX=#{prefix}"
+
+    # Carthage puts some stuff in /tmp so clean it up after we're done.
+    system "make", "clean"
+  end
+
+  test do
+    (testpath/"Cartfile").write 'github "jspahrsummers/xcconfigs"'
+    system "#{bin}/carthage", "update"
+  end
+end