Subject: bug#72750: 29.3; indent-region changes semantics of python code

From: Michael Arndt <[email-masked]>
Date: Wed, 21 Aug 2024 20:06:52 +0200

Hi,

I have a problem when indenting python files. There seems to be a case
when using indent-region changes the semantics of the python code. When
there is no blank line after an if-statement, the next line becomes part
of the if statement.

The problem can be reproduced by the following steps:

1. Start emacs -Q
2. Create a python file with the following contents:

if False:
      print("output1")
print("output2")

3. Use M-x mark-whole-buffer
4. Use M-x indent-region
5. The file contents change into:

if False:
      print("output1")
      print("output2")

The problem can be avoided by adding a blank line after the if statement.
Because I use a custom indentation function that calls (indent-region
(point-min) (point-max)) this can happen pretty quickly. Is this a
limitation of python-indent-region?

Greetings
Michael

In GNU Emacs 29.3 (build 1, x86_64-pc-linux-gnu, GTK+ Version 2.24.33,
cairo version 1.18.0) of 2024-04-02 built on titan
Repository revision: ae8f815613c2e072e92aa8fe7b4bcf2fdabc7408
Repository branch: HEAD
Windowing system distributor 'The X.Org Foundation', version 11.0.12101011
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