 
   # Public: Returns true for extensions associated with compressed files.
   isCompressedExtension: (ext) ->
-    _.has(COMPRESSED_EXTENSIONS, ext)
+    COMPRESSED_EXTENSIONS.hasOwnProperty(ext)
 
   # Public: Returns true for extensions associated with image files.
   isImageExtension: (ext) ->
-    _.has(IMAGE_EXTENSIONS, ext)
+    IMAGE_EXTENSIONS.hasOwnProperty(ext)
 
   # Public: Returns true for extensions associated with pdf files.
   isPdfExtension: (ext) ->


  # Public: Returns true for extensions associated with binary files.
  isBinaryExtension: (ext) ->
    _.has(BINARY_EXTENSIONS, ext)

  # Public: Returns true for files named similarily to 'README'
  isReadmePath: (readmePath) ->


  # Public: Returns true for extensions associated with Markdown files.
  isMarkdownExtension: (ext) ->
    MARKDOWN_EXTENSIONS.hasOwnProperty(ext)

  # Public: Is the filesystem case insensitive?
  #
