Tweaks to Python 3.x

Take features from Python (2.x) formula up to the Python 3.x formula.

Formula/python3.rb

@@ -1,30 +1,56 @@
-# Lightly modified from the Python 2.6.5 formula.
 require 'formula'
 
+<<-COMMENTS
+Versions
+--------
+This formula is currently tracking version 3.1.x.
+
+Python 2.x is available as a separate formula:
+  brew install python
+
+COMMENTS
+
+# Was a Framework build requested?
+def build_framework?; ARGV.include? '--framework'; end
+
+# Are we installed or installing as a Framework?
+def as_framework?
+  (self.installed? and File.exists? prefix+"Frameworks/Python.framework") or build_framework?
+end
+
 class Python3 <Formula
   url 'http://www.python.org/ftp/python/3.1.2/Python-3.1.2.tar.bz2'
   homepage 'http://www.python.org/'
   md5 '45350b51b58a46b029fb06c61257e350'
 
-  depends_on 'readline' => :optional  # Prefer over OS X's libedit.
-  depends_on 'sqlite' => :optional  # Prefer over OS X's copy.
+  depends_on 'readline' => :optional  # Prefer over OS X's libedit
+  depends_on 'sqlite'   => :optional  # Prefer over OS X's older version
   depends_on 'gdbm'     => :optional
-  # With all dependencies installed should only have ossaudiodev and spwd not
-  # built from the stdlib.
 
   def options
     [
       ["--framework", "Do a 'Framework' build instead of a UNIX-style build."],
-      ["--universal", "Build for both 32 & 64 bit Intel."]
+      ["--universal", "Build for both 32 & 64 bit Intel."],
+      ["--static", "Build static libraries."]
     ]
   end
 
-  # XXX Overriding skip_clean? is deprecated
-  def skip_clean? path
-    # Need to keep the versioned binaries.
-    # Also, don't strip out pre-compiled # bytecode files.
-    path == bin+'python3' or path == bin+'python3.1' or
-    path == lib+'python3.1'
+  skip_clean ['bin', 'lib']
+
+  def site_packages
+    # The Cellar location of site-packages
+    if as_framework?
+      # If we're installed or installing as a Framework, then use that location.
+      return prefix+"Frameworks/Python.framework/Versions/3.1/lib/python3.1/site-packages"
+    else
+      # Otherwise, use just the lib path.
+      return lib+"python3.1/site-packages"
+    end
+  end
+
+  def prefix_site_packages
+    # The HOMEBREW_PREFIX location of site-packages
+    HOMEBREW_PREFIX+"lib/python3.1/site-packages"
   end
 
   def install
@@ -32,13 +58,33 @@ class Python3 <Formula
     # both gcc and LLVM support this, so switch it on.
     args = ["--prefix=#{prefix}", "--with-computed-gotos"]
 
-    args << "--enable-framework" if ARGV.include? '--framework'
     if ARGV.include? '--universal'
-      args.push "--enable-universalsdk=/", "--with-universal-archs=intel"
+      args << "--enable-universalsdk=/" << "--with-universal-archs=intel"
+    end
+
+    if build_framework?
+      args << "--enable-framework=#{prefix}/Frameworks"
+    else
+      args << "--enable-shared" unless ARGV.include? '--static'
     end
 
     system "./configure", *args
     system "make"
+    ENV.j1 # Installs must be serialized
     system "make install"
+
+    # Add the Homebrew prefix path to site-packages via a .pth
+    prefix_site_packages.mkpath
+    (site_packages+"homebrew.pth").write prefix_site_packages
+  end
+
+  def caveats
+    <<-EOS.undent
+      The site-packages folder for this Python is:
+        #{site_packages}
+
+      We've added a "homebrew.pth" file to also include:
+        #{prefix_site_packages}
+    EOS
   end
 end