From: Rick DeNatale <rick.denatale@...>
Date: 2009-09-19T03:58:03+09:00
Subject: Re: Compare 2 files with different names (checksum?)

On Fri, Sep 18, 2009 at 12:05 PM, Max Williams
<toastkid.williams@gmail.com> wrote:
> Hey all
>
> I've been using File.compare to see if two files are the same, but now i
> have the case where one is a renamed copy of the other.  I'd like to
> treat these two as the same in this case.  Can anyone suggest a test
> that doesn't care about names?
>
> The files that have been renamed are xml (ie text format) if that makes
> life easier but a solution that works with binaries as well would be
> ideal.
>
> I've been trying to google checksums in ruby but haven't seen a useful
> example, maybe i was just being blind.  Will a checksum ignore the name
> of the file?

google for Ruby digest.  A SHA1 hash is a good alternative.

require 'digest/sha1'

def contents_equal?(path_to_file_1, path_to_file_2)
   Digest::SHA1.file(path_to_file_1).hexdigest ==
Digest::SHA1.file(path_to_file_2).hexdigest
end


-- 
Rick DeNatale

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