#748 Rename local changes named-parameter arguments

[Gunnlaugur Thor Briem]

When using the Rename refactoring to rename a local variable inside a function, an occurrence of a named parameter with the same name is changed also. Example:

def t_plus_three(dt, holidays):
days = 0
while(days < 3):
dt = dt + datetime.timedelta(days = 1)
if(dt.isoweekday() < 6 and not dt in holidays):
days = days + 1
return dt

When I try to rename the local variable "days" to "biz_days", I get this:

dt = dt + datetime.timedelta(biz_days = 1)

which is of course incorrect.

That's not a big deal in this case (it produces a compile-time TypeError so you can't miss it) but could easily introduce sneaky bugs in cases where a named parameter with the new name also exists.