leiningen: disable autoinstall/autoupdate

Fixes Homebrew/homebrew#21398.

Formula/leiningen.rb

@@ -1,5 +1,10 @@
 require 'formula'
 
+class LeiningenJar < Formula
+  url 'https://leiningen.s3.amazonaws.com/downloads/leiningen-2.2.0-standalone.jar', :using => :nounzip
+  sha1 '694c01251f71954e9d1d7003b42dee1b3a393191'
+end
+
 class Leiningen < Formula
   homepage 'https://github.com/technomancy/leiningen'
   url 'https://github.com/technomancy/leiningen/archive/2.2.0.tar.gz'
@@ -8,14 +13,18 @@ class Leiningen < Formula
   head 'https://github.com/technomancy/leiningen.git'
 
   def install
-    bin.install "bin/lein"
-    system "#{bin}/lein", "self-install"
+    LeiningenJar.new.brew { libexec.install 'leiningen-2.2.0-standalone.jar' }
+    # bin/lein autoinstalls and autoupdates, which doesn't work too well for us
+    inreplace "bin/lein-pkg" do |s|
+      s.change_make_var! 'LEIN_JAR', libexec/'leiningen-2.2.0-standalone.jar'
+    end
+    bin.install "bin/lein-pkg" => 'lein'
     bash_completion.install 'bash_completion.bash' => 'lein-completion.bash'
     zsh_completion.install 'zsh_completion.zsh' => '_lein'
   end
 
   def caveats; <<-EOS.undent
-    Standalone jar and dependencies installed to:
+    Dependencies will be installed to:
       $HOME/.m2/repository
     EOS
   end