diff tests/test-chg.t @ 44261:04a3ae7aba14

chg: force-set LC_CTYPE on server start to actual value from the environment

Python 3.7+ will "coerce" the LC_CTYPE variable in many instances, and this can
cause issues with chg being able to start up. D7550 attempted to fix this, but a
combination of a misreading of the way that python3.7 does the coercion and an
untested state (LC_CTYPE being set to an invalid value) meant that this was
still not quite working.

This change will cause differences between chg and hg: hg will have the LC_CTYPE
environment variable coerced, while chg will not. This is unlikely to cause any
detectable behavior differences in what Mercurial itself outputs, but it does
have two known effects:

-   When using hg, the coerced LC_CTYPE will be passed to subprocesses, even
    non-python ones. Using chg will remove the coercion, and this will not
    happen. This is arguably more correct behavior on chg's part.
-   On macOS, if you set your region to Brazil but your language to English,
    this isn't representable in locale strings, so macOS sets LC_CTYPE=UTF-8. If
    this value is passed along when ssh'ing to a non-macOS machine, some
    functions (such as locale.setlocale()) may raise an exception due to an
    unsupported locale setting. This is most easily encountered when doing an
    interactive commit/split/etc. when using ui.interface=curses.

Differential Revision: https://phab.mercurial-scm.org/D8039

--- a/tests/test-chg.t	Mon Feb 03 09:00:05 2020 +0100
+++ b/tests/test-chg.t	Wed Jan 29 13:39:50 2020 -0800
@@ -332,8 +332,8 @@
   YYYY/MM/DD HH:MM:SS (PID)> log -R cached
   YYYY/MM/DD HH:MM:SS (PID)> loaded repo into cache: $TESTTMP/cached (in  ...s)
 
-Test that chg works even when python "coerces" the locale (py3.7+, which is done
-by default if none of LC_ALL, LC_CTYPE, or LANG are set in the environment)
+Test that chg works (sets to the user's actual LC_CTYPE) even when python
+"coerces" the locale (py3.7+)
 
   $ cat > $TESTTMP/debugenv.py <<EOF
   > from mercurial import encoding
@@ -347,9 +347,22 @@
   >         if v is not None:
   >             ui.write(b'%s=%s\n' % (k, encoding.environ[k]))
   > EOF
+(hg keeps python's modified LC_CTYPE, chg doesn't)
+  $ (unset LC_ALL; unset LANG; LC_CTYPE= "$CHGHG" \
+  >    --config extensions.debugenv=$TESTTMP/debugenv.py debugenv)
+  LC_CTYPE=C.UTF-8 (py37 !)
+  LC_CTYPE= (no-py37 !)
+  $ (unset LC_ALL; unset LANG; LC_CTYPE= chg \
+  >    --config extensions.debugenv=$TESTTMP/debugenv.py debugenv)
+  LC_CTYPE=
+  $ (unset LC_ALL; unset LANG; LC_CTYPE=unsupported_value chg \
+  >    --config extensions.debugenv=$TESTTMP/debugenv.py debugenv)
+  LC_CTYPE=unsupported_value
+  $ (unset LC_ALL; unset LANG; LC_CTYPE= chg \
+  >    --config extensions.debugenv=$TESTTMP/debugenv.py debugenv)
+  LC_CTYPE=
   $ LANG= LC_ALL= LC_CTYPE= chg \
   >    --config extensions.debugenv=$TESTTMP/debugenv.py debugenv
   LC_ALL=
-  LC_CTYPE=C.UTF-8 (py37 !)
-  LC_CTYPE= (no-py37 !)
+  LC_CTYPE=
   LANG=