From 921f0e567420b841be535b1e9acf20d8320cb2ea Mon Sep 17 00:00:00 2001
From: Max Howell <max@methylblue.com>
Date: Tue, 6 Mar 2012 02:23:01 +0000
Subject: [PATCH] `brew update` will update taps

---
 Library/Homebrew/cmd/update.rb | 268 +++++++++++++--------------------
 1 file changed, 107 insertions(+), 161 deletions(-)

diff --git a/Library/Homebrew/cmd/update.rb b/Library/Homebrew/cmd/update.rb
index 7e4157a03c..3d77137844 100644
--- a/Library/Homebrew/cmd/update.rb
+++ b/Library/Homebrew/cmd/update.rb
@@ -1,192 +1,138 @@
 module Homebrew extend self
+
   def update
     abort "Please `brew install git' first." unless system "/usr/bin/which -s git"
 
-    updater = RefreshBrew.new
-    if updater.update_from_masterbrew!
-      updater.report
-    else
-      puts "Already up-to-date."
-    end
-  end
-end
-
-class RefreshBrew
-  REPOSITORY_URL = "https://github.com/mxcl/homebrew.git"
-  FORMULA_DIR = 'Library/Formula/'
-  EXAMPLE_DIR = 'Library/Contributions/examples/'
-
-  attr_reader :added_formulae, :updated_formulae, :deleted_formulae, :installed_formulae
-  attr_reader :added_examples, :deleted_examples
-  attr_reader :initial_revision, :current_revision
-
-  def initialize
-    @added_formulae, @updated_formulae, @deleted_formulae, @installed_formulae = [], [], [], []
-    @added_examples, @deleted_examples = [], [], []
-    @initial_revision, @current_revision = nil
-  end
-
-  # Performs an update of the homebrew source. Returns +true+ if a newer
-  # version was available, +false+ if already up-to-date.
-  def update_from_masterbrew!
     # ensure GIT_CONFIG is unset as we need to operate on .git/config
     ENV.delete('GIT_CONFIG')
 
-    HOMEBREW_REPOSITORY.cd do
-      if git_repo?
-        safe_system "git checkout -q master"
-        @initial_revision = read_revision
-        # originally we fetched by URL but then we decided that we should
-        # use origin so that it's easier for forks to operate seamlessly
-        unless `git remote`.split.include? 'origin'
-          safe_system "git remote add origin #{REPOSITORY_URL}"
-        end
-      else
-        begin
-          safe_system "git init"
-          safe_system "git config core.autocrlf false"
-          safe_system "git remote add origin #{REPOSITORY_URL}"
-          safe_system "git fetch origin"
-          safe_system "git reset --hard origin/master"
-        rescue Exception
-          safe_system "/bin/rm -rf .git"
-          raise
+    cd HOMEBREW_REPOSITORY
+    git_init_if_necessary
+
+    report = Report.new
+    master_updater = Updater.new
+    master_updater.pull!
+    report.merge!(master_updater.report)
+
+    Dir["Library/Taps/*"].each do |tapd|
+      cd tapd do
+        updater = Updater.new
+        updater.pull!
+        report.merge!(updater.report) do |key, oldval, newval|
+          oldval.concat(newval)
         end
       end
-
-      # ensure we don't munge line endings on checkout
-      safe_system "git config core.autocrlf false"
-      # specify a refspec so that 'origin/master' gets updated
-      refspec = "refs/heads/master:refs/remotes/origin/master"
-      rebase = "--rebase" if ARGV.include? "--rebase"
-      execute "git pull #{rebase} origin #{refspec}"
-      @current_revision = read_revision
     end
 
-    if initial_revision && initial_revision != current_revision
-      # hash with status characters for keys:
-      # Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R)
-      @changes_map = Hash.new {|h,k| h[k] = [] }
-
-      changes = HOMEBREW_REPOSITORY.cd do
-        execute("git diff-tree -r --name-status -z #{initial_revision} #{current_revision}").split("\0")
-      end
-
-      while status = changes.shift
-        file = changes.shift
-        @changes_map[status] << file
-      end
-
-      if @changes_map.any?
-        @added_formulae   = changed_items('A', FORMULA_DIR)
-        @deleted_formulae = changed_items('D', FORMULA_DIR)
-        @updated_formulae = changed_items('M', FORMULA_DIR)
-        @added_examples   = changed_items('A', EXAMPLE_DIR)
-        @deleted_examples = changed_items('D', EXAMPLE_DIR)
-        @added_internal_commands = changed_items('A', "Library/Homebrew/cmd")
-        @deleted_internal_commands = changed_items('D', "Library/Homebrew/cmd")
-
-        @installed_formulae = HOMEBREW_CELLAR.children.
-          select{ |pn| pn.directory? }.
-          map{ |pn| pn.basename.to_s }.sort if HOMEBREW_CELLAR.directory?
-
-        return true
-      end
-    end
-    # assume nothing was updated
-    return false
-  end
-
-  def git_repo?
-    Dir['.git/*'].length > 0
-  end
-
-  def pending_formulae_changes?
-    !@updated_formulae.empty?
-  end
-
-  def pending_new_formulae?
-    !@added_formulae.empty?
-  end
-
-  def deleted_formulae?
-    !@deleted_formulae.empty?
-  end
-
-  def pending_examples_changes?
-    !@updated_examples.empty?
-  end
-
-  def pending_new_examples?
-    !@added_examples.empty?
-  end
-
-  def deleted_examples?
-    !@deleted_examples.empty?
-  end
-
-  def report
-    puts "Updated Homebrew from #{initial_revision[0,8]} to #{current_revision[0,8]}."
-    if pending_new_formulae?
-      ohai "New formulae"
-      puts_columns added_formulae
-    end
-    if deleted_formulae?
-      ohai "Removed formulae"
-      puts_columns deleted_formulae, installed_formulae
-    end
-    if pending_formulae_changes?
-      ohai "Updated formulae"
-      puts_columns updated_formulae, installed_formulae
-    end
-
-    unless @added_internal_commands.empty?
-      ohai "New commands"
-      puts_columns @added_internal_commands
-    end
-    unless @deleted_internal_commands.empty?
-      ohai "Removed commands"
-      puts_columns @deleted_internal_commands
-    end
-
-    # external commands aren't generally documented but the distinction
-    # is loose. They are less "supported" and more "playful".
-    if pending_new_examples?
-      ohai "New external commands"
-      puts_columns added_examples
-    end
-    if deleted_examples?
-      ohai "Removed external commands"
-      puts_columns deleted_examples
+    if report.empty?
+      puts "Already up-to-date."
+    else
+      puts "Updated Homebrew from #{master_updater.initial_revision[0,8]} to #{master_updater.current_revision[0,8]}."
+      report.dump
     end
   end
 
   private
 
-  def read_revision
-    execute("git rev-parse HEAD").chomp
+  def git_init_if_necessary
+    if Dir['.git/*'].empty?
+      safe_system "git init"
+      safe_system "git config core.autocrlf false"
+      safe_system "git remote add origin https://github.com/mxcl/homebrew.git"
+      safe_system "git fetch origin"
+      safe_system "git reset --hard origin/master"
+    end
+  rescue Exception
+    FileUtils.rm_rf ".git"
+    raise
   end
 
-  def filter_by_directory(files, dir)
-    files.select { |f| f.index(dir) == 0 }
+end
+
+class Updater
+  attr_reader :initial_revision, :current_revision
+
+  def pull!
+    safe_system "git checkout -q master"
+
+    @initial_revision = read_current_revision
+
+    # ensure we don't munge line endings on checkout
+    safe_system "git config core.autocrlf false"
+
+    args = ["pull"]
+    args << "--rebase" if ARGV.include? "--rebase"
+    args << "-q" unless ARGV.verbose?
+    args << "origin"
+    # the refspec ensures that 'origin/master' gets updated
+    args << "refs/heads/master:refs/remotes/origin/master"
+
+    safe_system "git", *args
+
+    @current_revision = read_current_revision
   end
 
-  def basenames(files)
-    files.map { |f| File.basename(f, '.rb') }
+  def report
+    map = Hash.new{ |h,k| h[k] = [] }
+
+    if initial_revision && initial_revision != current_revision
+      changes = `git diff-tree -r --name-status -z #{initial_revision} #{current_revision}`.split("\0")
+      changes.each_slice(2) do |status, file|
+        file = Pathname.pwd.join(file).relative_path_from(HOMEBREW_REPOSITORY)
+        map[status.to_sym] << file.to_s
+      end
+    end
+
+    map
   end
 
-  # extracts items by status from @changes_map
-  def changed_items(status, dir)
-    basenames(filter_by_directory(@changes_map[status], dir)).sort
+  private
+
+  def read_current_revision
+    `git rev-parse HEAD`.chomp
   end
 
-  def execute(cmd)
-    out = `#{cmd}`
+  def `(cmd)
+    out = Kernel.`(cmd) #`
     if $? && !$?.success?
       $stderr.puts out
-      raise "Failed while executing #{cmd}"
+      raise ErrorDuringExecution, "Failure while executing: #{cmd}"
     end
     ohai(cmd, out) if ARGV.verbose?
     out
   end
 end
+
+
+class Report < Hash
+
+  def dump
+    # Key Legend: Added (A), Copied (C), Deleted (D), Modified (M), Renamed (R)
+
+    dump_formula_report :A, "New Formula"
+    dump_formula_report :M, "Updated Formula"
+    dump_formula_report :D, "Deleted Formula"
+    dump_formula_report :R, "Renamed Formula"
+#    dump_new_commands
+#    dump_deleted_commands
+  end
+
+  def select_formula key
+    fetch(key, []).map do |path|
+      case path when %r{^Library/Formula}
+        File.basename(path, ".rb")
+      when %r{^Library/Taps/(\w+)-(\w+)/(.*)}
+        "#$1/#$2/#{File.basename(path, '.rb')}"
+      end
+    end.compact.sort
+  end
+
+  def dump_formula_report key, title
+    formula = select_formula(key)
+    unless formula.empty?
+      ohai title
+      puts_columns formula
+    end
+  end
+
+end