Always create a REVISION file when building a package.

Rakefile

@@ -53,12 +53,6 @@ END
   require 'rake/gempackagetask'
   require 'lib/haml'
 
-  # Before we run the package task,
-  # we want to create a REVISION file
-  # if we've checked out Haml from git
-  # and we aren't building for a release.
-  create_revision = Haml.version[:rev] && !Rake.application.top_level_tasks.include?('release')
-
   spec = Gem::Specification.new do |spec|
     spec.name = 'haml'
     spec.summary = "An elegant, structured XHTML/XML templating engine.\nComes with Sass, a similar CSS templating engine."
@@ -79,9 +73,9 @@ END
     readmes = FileList.new('*') do |list|
       list.exclude(/(^|[^.a-z])[a-z]+/)
       list.exclude('TODO')
+      list.include('REVISION')
     end.to_a
     spec.executables = ['haml', 'html2haml', 'sass', 'css2sass']
-    readmes << 'REVISION' if create_revision
     spec.files = FileList['lib/**/*', 'bin/*', 'test/**/*', 'Rakefile', 'init.rb'].to_a + readmes
     spec.autorequire = ['haml', 'sass']
     spec.homepage = 'http://haml.hamptoncatlin.com/'
@@ -105,7 +99,13 @@ END
 
   desc "This is an internal task."
   task :revision_file do
-    File.open('REVISION', 'w') { |f| f.puts Haml.version[:rev] } if create_revision
+    if Haml.version[:rev] && !Rake.application.top_level_tasks.include?('release')
+      File.open('REVISION', 'w') { |f| f.puts Haml.version[:rev] }
+    elsif Rake.application.top_level_tasks.include?('release')
+      File.open('REVISION', 'w') { |f| f.puts "(release)" }
+    else
+      File.open('REVISION', 'w') { |f| f.puts "(unknown)" }
+    end
   end
   Rake::Task[:package].prerequisites.insert(0, :revision_file)
 

lib/haml.rb

@@ -937,7 +937,10 @@ module Haml
 
     if File.exists?(scope('REVISION'))
       rev = File.read(scope('REVISION')).strip
-    elsif File.exists?(scope('.git/HEAD'))
+      rev = nil if rev !~ /a-f0-9+/
+    end
+
+    if rev.nil? && File.exists?(scope('.git/HEAD'))
       rev = File.read(scope('.git/HEAD')).strip
       if rev =~ /^ref: (.*)$/
         rev = File.read(scope(".git/#{$1}")).strip