Subject: [bug#29856] [PATCH core-updates] guix: python-build-system:, Modify ".py" files in-place.

From: Hartmut Goebel <[email-masked]>
Date: Tue, 2 Jan 2018 17:13:15 +0100

Hi,

I'm afraid, this patch will lead to quite some serious problems:

  * It "kills" the doc-string, which must be the very first
    expression-statement in the program. This might be rarely used, but
  * it kills "from __future__ import", which must be the first import
    statement (or even the first statement after any doc-string) to work.

Fixing these issues would require to implement a language-aware scanner,
as discussed in
<https://lists.gnu.org/archive/html/guix-devel/2017-11/msg00022.html>.

Thus I suggest aiming to implement the solution discussed in that thread
(see esp.
<https://lists.gnu.org/archive/html/guix-devel/2017-11/msg00041.html>.

Beside of this, the patch suffers from some more issues. Sorry to say :-(

  * When converting PYTHONPATH into a list of python strings, these need
    to be quoted properly.
  * The description (commit-message) of the patch is much to terse. It
    should describe the the reason and implications. Esp. it should
    describe the case this is fixing.

BTW: The first analysis in <https://bugs.gnu.org/29824> was misleading.
I commented there.

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | [email-masked]               |
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