+review changes

Author: manovasanth1227

lib/docx/document.rb

@@ -25,6 +25,7 @@ def initialize(path_or_io, options = {})
 
       # if path-or_io is string && does not contain a null byte
       if (path_or_io.instance_of?(String) && !/\u0000/.match?(path_or_io))
+        raise Errno::EIO.new('invalid file format') if !File.extname(path_or_io).eql?('.docx')
         @zip = Zip::File.open(path_or_io)
       else
         @zip = Zip::File.open_buffer(path_or_io)
@@ -37,8 +38,6 @@ def initialize(path_or_io, options = {})
       @doc = Nokogiri::XML(@document_xml)
       load_styles
       yield(self) if block_given?
-    rescue Zip::Error => e
-      raise 'File not supported'
     ensure
       @zip.close unless @zip.nil?
     end