[tahoe-dev] [tahoe-lafs] #943: "tahoe mv" deleted my files?

[tahoe-lafs]

#943: "tahoe mv" deleted my files?
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 Reporter:  zooko                            |           Owner:       
     Type:  defect                           |          Status:  new  
 Priority:  major                            |       Milestone:  1.6.1
Component:  code-frontend-cli                |         Version:  1.6.0
 Keywords:  tahoe-mv usability preservation  |   Launchpad_bug:       
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Comment(by davidsarah):

 Normally, {{{tahoe mv}}} would not result in any data loss because the
 issuer of the command must have the cap that starts the destination path.
 In the case described in this bug, however, we delete one of the links in
 that path, because it is the same as the source link.

 Therefore, the potential data loss can be fixed by checking whether any of
 the destination links are the same as the link that is to be moved. This
 should match the expectations of users accustomed to Unix {{{mv}}} or
 moving files in a Windows filesystem, which would fail in the same
 situation. Note that we are '''not''' enforcing that it is impossible to
 create loops using {{{tahoe mv}}} -- that's not necessary to fix this bug.

 The link to be moved must be from a mutable directory, therefore it has an
 SI. So, the definition of "same as" for links can be "same parent
 directory SI, and same child name" (comparing child names as Unicode
 strings without normalization).

 The later {{{mv}}}s reporting OK is a separate issue that we haven't
 investigated yet.

-- 
Ticket URL: <http://allmydata.org/trac/tahoe/ticket/943#comment:4>
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