[Python-Dev] Need some patches checked (original) (raw)

Guido van Rossum guido@python.org
Sun, 11 May 2003 20:20:18 -0400

Since I am trying to tackle patches that were not written by me for the first time I need someone to check that I am doing the right thing.

http://www.python.org/sf/649742 is a patch to make adding headers to urllib2's Request object have consistent case. I cleaned up the patch and everything seems reasonable and I don't see how doing this will hurt backwards-compatibilty short of code that tried to add multiple headers of the same name with different case which is not legal anyway for HTTP.

Good! I just noticed with disgust that the headers dict is case currently case-sensitive, so that if I want to change the Content-type header, I have to use the exact case used in the source. I can't imagine b/w compatibility issues with this.

http://www.python.org/sf/639139 is a patch wanting to remove an isinstance assertion. Raymond initially suggested weakening the assertion to doing attribute checks. I personally see no reason we can't just take the check out entirely since the code does not appear to have any place where it will mask an AttributeError exception and the comment for the assert says it is just for checking the interface. But since Raymond initially wanted to go another direction I need someone to step in and give me some advice (or Raymond can look at it again; patch is old).

The advantage of the assert (or some other check) is to catch a type error early, rather than 4 call levels deeper, where the source of the AttributeError may not be obvious when it happens. But I agree that that is a minor issue, and for correct code removing the assert is fine. Checking exactly for the attributes that are (or may be) used is probably overly expensive.

--Guido van Rossum (home page: http://www.python.org/~guido/)