Wrong warning "unknown keyword argument"

[linuswagner]

When I execute the following lines:

import Node;
getKeywordParameters("f"(10, "abc", height=0));

I get

Warning: calling function with extra unknown keyword argument: height
map[str, value]: ("height":0)

The warning comes from interprete(), specifically here.

The way I understand the code through the debugger, kwFormals is something empty-like, so the whole outer if around the warning should be skipped. However, the check fails and evaluates to true.

Did I spot the bug correctly?

[linuswagner]

Also thanks Lisa for observing the warning in the first place!