compilemessages shouldn't return with exit code 0 when it fails

[Aymeric Augustin]

When compilemessages is run on a read-only location, it displays a messages to standard error and terminates with exit code 0. It should have exit code 1.

Patch:

diff --git a/django/core/management/commands/compilemessages.py b/django/core/management/commands/compilemessages.py
index dbadac0..75f3c57 100644
--- a/django/core/management/commands/compilemessages.py
+++ b/django/core/management/commands/compilemessages.py
@@ -108,9 +108,9 @@ class Command(BaseCommand):
 
             # Check writability on first location
             if i == 0 and not is_writable(npath(base_path + '.mo')):
-                self.stderr.write("The po files under %s are in a seemingly not writable location. "
-                                  "mo files will not be updated/created." % dirpath)
-                return
+                raise CommandError("The po files under %s are in a seemingly "
+                                   "not writable location. mo files will not "
+                                   "be updated/created." % dirpath)
 
             args = [self.program] + self.program_options + ['-o',
                     npath(base_path + '.mo'), npath(base_path + '.po')]

With this change, the output is exactly the same, but the exit code reflects the failure and the --traceback option works.

I don't quite have the motivation to write tests for this change :-/

[Claude Paroz]

The reason of the current behaviour is that compilemessages run compile_messages for all paths of settings.LOCALE_PATHS. The idea was to not stop running the command if only one path is read-only but not the others. When #24159 will be fixed, it's probable that compile_messages will be launched for all apps in INSTALLED_APPS. Then we don't want to fail when some app is read-only (maybe a third-party app in a non-readable location).

[Aymeric Augustin]

We have a problem akin to test discovery here. I think the right solution is to ignore anything outside the current working directory and error if a non-writable location is encountered.

[Claude Paroz]

See #21732 for the initial use case about non-writable paths.

Ignoring paths outside current directory could be a solution, but might be backwards incompatible.

[Claude Paroz]

​PR

[Claude Paroz <claude@…>]

In a77f2188:

Fixed #24384 -- Allowed compilemessages to continue running after nonfatal errors.

Thanks Aymeric Augustin for the report and Carlton Gibson and Tim Graham for
the reviews.