diff mercurial/util.py @ 44436:09f3e003fc2a

phabricator: avoid a stacktrace when command arguments are missing

Previously, the TypeError wasn't properly converted to a SignatureError when
improper arguments were supplied to the inner function, because the stack depth
is 2 inside the vcrcommand decorator.  The `__name__` and `__doc__` attributes
need to be reassigned to the new wrapper so that the help summary is available.

Differential Revision: https://phab.mercurial-scm.org/D8209

--- a/mercurial/util.py	Fri Jan 24 15:51:19 2020 -0800
+++ b/mercurial/util.py	Wed Mar 04 00:45:54 2020 -0500
@@ -1846,14 +1846,14 @@
     return pycompat.ossep.join(([b'..'] * len(a)) + b) or b'.'
 
 
-def checksignature(func):
+def checksignature(func, depth=1):
     '''wrap a function with code to check for calling errors'''
 
     def check(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except TypeError:
-            if len(traceback.extract_tb(sys.exc_info()[2])) == 1:
+            if len(traceback.extract_tb(sys.exc_info()[2])) == depth:
                 raise error.SignatureError
             raise