bpo-38821: Fix crash in argparse when using gettext (GH-17192)
diff --git a/Lib/argparse.py b/Lib/argparse.py
index 94e1b8a..5a8eff2 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -2148,10 +2148,11 @@
OPTIONAL: _('expected at most one argument'),
ONE_OR_MORE: _('expected at least one argument'),
}
- default = ngettext('expected %s argument',
+ msg = nargs_errors.get(action.nargs)
+ if msg is None:
+ msg = ngettext('expected %s argument',
'expected %s arguments',
action.nargs) % action.nargs
- msg = nargs_errors.get(action.nargs, default)
raise ArgumentError(action, msg)
# return the number of arguments matched
diff --git a/Misc/NEWS.d/next/Library/2019-11-16-23-26-25.bpo-38821.-albNN.rst b/Misc/NEWS.d/next/Library/2019-11-16-23-26-25.bpo-38821.-albNN.rst
new file mode 100644
index 0000000..2e7a22f
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-11-16-23-26-25.bpo-38821.-albNN.rst
@@ -0,0 +1 @@
+Fix unhandled exceptions in :mod:`argparse` when internationalizing error messages for arguments with ``nargs`` set to special (non-integer) values. Patch by Federico Bond.