Extract Environment#absolute? into Sprockets.absolute? and make it wo…

…rk right on Windows.

lib/sprockets.rb

@@ -3,6 +3,33 @@
 require "yaml"
 require "fileutils"
 
+module Sprockets
+  class << self
+    def running_on_windows?
+      RUBY_PLATFORM =~ /(win|w)32$/
+    end
+
+    def absolute?(location)
+      same_when_expanded?(location) || platform_absolute_path?(location)
+    end
+
+    protected
+      def same_when_expanded?(location)
+        location[0, 1] == File.expand_path(location)[0, 1]
+      end
+
+      def platform_absolute_path?(location)
+        false
+      end
+
+      if Sprockets.running_on_windows?
+        def platform_absolute_path?(location)
+          location[0, 1] == File::SEPARATOR && File.expand_path(location) =~ /[A-Za-z]:[\/\\]/
+        end
+      end
+  end
+end
+
 require "sprockets/version"
 require "sprockets/error"
 require "sprockets/environment"
@@ -12,3 +39,4 @@
 require "sprockets/concatenation"
 require "sprockets/preprocessor"
 require "sprockets/secretary"
+

lib/sprockets/environment.rb

@@ -22,7 +22,7 @@ def register_load_location(location)
     end
 
     def find(location)
-      if absolute?(location) && File.exists?(location)
+      if Sprockets.absolute?(location) && File.exists?(location)
         pathname_from(location)
       else
         find_all(location).first
@@ -39,13 +39,9 @@ def constants(reload = false)
     end
 
     protected
-      def absolute?(location)
-        location[0, 1] == File::SEPARATOR
-      end
-
       def absolute_location_from(location)
         location = location.to_s
-        location = File.join(root.absolute_location, location) unless absolute?(location)
+        location = File.join(root.absolute_location, location) unless Sprockets.absolute?(location)
         File.expand_path(location)
       end
 

lib/sprockets/secretary.rb

@@ -72,7 +72,7 @@ def expand_paths(paths, options = {})
       end
 
       def from_root(path)
-        if path[0, 1] == File::SEPARATOR
+        if Sprockets.absolute?(path)
           path
         else
           File.join(@options[:root], path)