National encodings support enhancement

[Former user]

Adds new engine parameter (client_encoding) and makes all strings coming to/from client from/to server to be converted using this encoding.

Also adds automatic convertion to Unicode column types if "client_encoding" is specified

[Former user]

simple test script

[Former user]

It seems to me that there is an error in encodings.diff. Function convert_result_value is receiving strings from database, not from client, so it shouldn't convert values like this:

20  +                return unicode(value, engine.client_encoding).encode(engine.encoding)

but like this:

20  +                return unicode(value, engine.encoding).encode(engine.client_encoding)

You could also consider avoiding conversion if engine.encoding == engine.client_encoding like this:

10  +            if engine.client_encoding and engine.client_encoding!=engine.encoding and isinstance(value, str):
19  +            if engine.client_encoding and engine.client_encoding!=engine.encoding and isinstance(value, str):

[Former user]

(original author: redvasily) Thank you, Qvx

You are right. Here's a corrected diff

[Former user]

diff corrected according to notes made by Qvx

[Mike Bayer]

this ones a little over my head, being an american and all, but there was some continued debate over the appropriateness of this one. since i am not thrilled about building extra conditionals into all string types by default, might want to see this implemented as an optional extension. going to mark as 'wontfix' for now.