This patch makes sure that the function name always appears in the error

message, and tries to make the messages more consistent and helpful when
the wrong number of arguments or duplicate keyword arguments are supplied.
Comes with more tests for test_extcall.py and and an update to an error
message in test/output/test_pyexpat.

Lib/test/test_extcall.py

@@ -1,5 +1,6 @@
 from UserList import UserList
 from test_support import TestFailed
+import string
 
 def f(*a, **k):
     print a, k
@@ -172,3 +173,32 @@ except TypeError:
     pass
 else:
     raise TestFailed, 'expected TypeError; no exception raised'
+
+a, b, d, e, v, k = 'A', 'B', 'D', 'E', 'V', 'K'
+funcs = []
+maxargs = {}
+for args in ['', 'a', 'ab']:
+    for defargs in ['', 'd', 'de']:
+        for vararg in ['', 'v']:
+            for kwarg in ['', 'k']:
+                name = 'z' + args + defargs + vararg + kwarg
+                arglist = list(args) + map(
+                    lambda x: '%s="%s"' % (x, x), defargs)
+                if vararg: arglist.append('*' + vararg)
+                if kwarg: arglist.append('**' + kwarg)
+                decl = 'def %s(%s): print "ok %s", a, b, d, e, v, k' % (
+                    name, string.join(arglist, ', '), name)
+                exec(decl)
+                func = eval(name)
+                funcs.append(func)
+                maxargs[func] = len(args + defargs)
+
+for name in ['za', 'zade', 'zabk', 'zabdv', 'zabdevk']:
+    func = eval(name)
+    for args in [(), (1, 2), (1, 2, 3, 4, 5)]:
+        for kwargs in ['', 'a', 'd', 'ad', 'abde']:
+            kwdict = {}
+            for k in kwargs: kwdict[k] = k + k
+            print func.func_name, args, kwdict, '->',
+            try: apply(func, args, kwdict)
+            except TypeError, err: print err