[GRASS-dev] [GRASS GIS] #3392: t.register: encoding error

[GRASS GIS]

#3392: t.register: encoding error
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  Reporter:  mlennert     |      Owner:  grass-dev@…
      Type:  defect       |     Status:  new
  Priority:  normal       |  Milestone:  7.2.2
 Component:  Temporal     |    Version:  svn-trunk
Resolution:               |   Keywords:  t.register encoding
       CPU:  Unspecified  |   Platform:  Unspecified
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Comment (by zarch):

 Hi Anna,

 Replying to [comment:12 annakrat]:
 > The problem mostly comes from calling gisenv function from script.utils
 which returns unicode. This was done some time ago to make the library
 Python3 compatible. So we eventually need to move towards unicode, but to
 have a quick fix for the release, we can keep the temporal library using
 bytestrings.


 I didn't have time to test your solution yet.

 Actually for me it is still not clear where should we use `unicode` and
 where `bytes`.
 Do you have some general guidelines?

 In the changes that I did, I transformed everything in bytes, and now the
 tests that I added to reproduce the ticket's error are passing, so the
 ticket is "theoretically" fixed. However this solution can only work with
 python2, because in the temporal library now I'm summing bytes with
 unicode, that can work only with python2 that does not distinguish between
 them.
 In python3 this operation raise an error. In general due to bytes
 limitation in python3 (mainly there is not format) perhaps we should use
 just unicode within the python code...

 Therefore I was thinking to replace all the `grass.script.utils` `encode`
 function that I added in `grass/lib/temporal` with `decode` to ensure that
 everything is unicode. And then replace the `print` function with
 `pygrass.messages.Messager` to eventually translate all the python unicode
 back to bytes just before printing them to system terminal.

 So I'm not sure when is the right moment to transform unicode to bytes.

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Ticket URL: <https://trac.osgeo.org/grass/ticket/3392#comment:13>
GRASS GIS <https://grass.osgeo.org>