From e8c0b01f24b12792c99440d672244fa7563a3a37 Mon Sep 17 00:00:00 2001
From: Adam Vandenberg <flangy@gmail.com>
Date: Sun, 29 Apr 2012 11:51:04 -0700
Subject: [PATCH] patches - support detection of compression types

---
 Library/Homebrew/formula.rb |  9 ++---
 Library/Homebrew/patches.rb | 73 ++++++++++++++++++++++++++-----------
 2 files changed, 56 insertions(+), 26 deletions(-)

diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 86985b7b9d..ed2cec904a 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -525,17 +525,16 @@ private
     patch_list = Patches.new(patches)
     return if patch_list.empty?
 
-    unless patch_list.external_curl_args.empty?
+    if patch_list.external_patches?
       ohai "Downloading patches"
-      # downloading all at once is much more efficient, especially for FTP
-      curl(*patch_list.external_curl_args)
+      patch_list.download!
     end
 
     ohai "Patching"
     patch_list.each do |p|
       case p.compression
-        when :gzip  then safe_system "/usr/bin/gunzip",  p.download_filename
-        when :bzip2 then safe_system "/usr/bin/bunzip2", p.download_filename
+        when :gzip  then safe_system "/usr/bin/gunzip",  p.compressed_filename
+        when :bzip2 then safe_system "/usr/bin/bunzip2", p.compressed_filename
       end
       # -f means don't prompt the user if there are errors; just exit with non-zero status
       safe_system '/usr/bin/patch', '-f', *(p.patch_args)
diff --git a/Library/Homebrew/patches.rb b/Library/Homebrew/patches.rb
index e3cab1ed92..a671782bca 100644
--- a/Library/Homebrew/patches.rb
+++ b/Library/Homebrew/patches.rb
@@ -15,9 +15,8 @@ class Patches
     end
   end
 
-  # Collects the urls and output names of all external patches
-  def external_curl_args
-    @patches.select{|p| p.external?}.collect{|p| p.curl_args}.flatten
+  def external_patches?
+    not external_curl_args.empty?
   end
 
   def each(&blk)
@@ -27,8 +26,26 @@ class Patches
     @patches.empty?
   end
 
+  def download!
+    return unless external_patches?
+
+    # downloading all at once is much more efficient, especially for FTP
+    curl(*external_curl_args)
+
+    external_patches.each{|p| p.stage!}
+  end
+
 private
 
+  def external_patches
+     @patches.select{|p| p.external?}
+  end
+
+  # Collects the urls and output names of all external patches
+  def external_curl_args
+    external_patches.collect{|p| p.curl_args}.flatten
+  end
+
   def normalize_patches patches
     if patches.kind_of? Hash
       patches
@@ -40,29 +57,21 @@ private
 end
 
 class Patch
+  # Used by formula to unpack after downloading
   attr_reader :compression
-  attr_reader :url
-  attr_reader :download_filename
+  attr_reader :compressed_filename
 
   def initialize patch_p, filename, url
     @patch_p = patch_p
     @patch_filename = filename
-    @compression = false
+    @compressed_filename = nil
+    @compression = nil
     @url = nil
 
     if url.kind_of? File # true when DATA is passed
       write_data url
     elsif looks_like_url(url)
-      @download_filename = @patch_filename
-      @url = url # Save URL
-      case @url
-      when /\.gz$/
-        @compression = :gzip
-        @download_filename += '.gz'
-      when /\.bz2$/
-        @compression = :bzip2
-        @download_filename += '.bz2'
-      end
+      @url = url # Save URL to mark this as an external patch
     else
       # it's a file on the local filesystem
       # use URL as the filename for patch
@@ -70,12 +79,22 @@ class Patch
     end
   end
 
-  def external?
-    !!@url
+  # rename the downloaded file to take compression into account
+  def stage!
+    return unless external?
+    detect_compression!
+    case @compression
+    when :gzip
+      @compressed_filename = @patch_filename + '.gz'
+      FileUtils.mv @patch_filename, @compressed_filename
+    when :bzip2
+      @compressed_filename = @patch_filename + '.bz2'
+      FileUtils.mv @patch_filename, @compressed_filename
+    end
   end
 
-  def compressed?
-    !!@compression
+  def external?
+    not @url.nil?
   end
 
   def patch_args
@@ -83,11 +102,23 @@ class Patch
   end
 
   def curl_args
-    [@url, '-o', @download_filename]
+    [@url, '-o', @patch_filename]
   end
 
 private
 
+  # Detect compression type from the downloaded patch.
+  def detect_compression!
+    # If nil we have not tried to detect yet
+    if @compression.nil?
+      path = Pathname.new(@patch_filename)
+      if path.exist?
+        @compression = path.compression_type
+        @compression ||= :none # If nil, convert to :none
+      end
+    end
+  end
+
   # Write the given file object (DATA) out to a local file for patch
   def write_data f
     pn = Pathname.new @patch_filename