Re: [PATCH] diffcore-rename: favour identical basenames

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 21, 2007, 17:52 UTC
Message-ID: <7vfy4lw5yk.fsf@assigned-by-dhcp.pobox.com>
In-Reply-To: <alpine.LFD.0.98.0706210910390.3593@woody.linux-foundation.org>

Linus Torvalds <torvalds@linux-foundation.org> writes:

Show 7 quoted lines

> We'e also had things like
>
> 	arch/i386/kernel/pci-pc.c -> arch/i386/kernel/pci/common.c
>
> so it's not always the ending of a file that is unchanged, but you still 
> often have some "similarity" of the name (ie the "pci" substring is still 
> common there).

This is not an example to draw very useful conclusions, is it?

The heuristics to say '-pc => common' is a more likely rename than '-obscure-arch => common' heavily depends on human intelligence in the context of a particular project, the kernel, where there are rules such as "peripherals are tested most widely on PC architectures, so assume that the vendors might have tested their stuff only on PCs".

But I do agree that not limiting to basename has values. Taking example from the "I cannot draw so here is a red big X", it is quite possible that two red big X's are replaced with properly rendered icons, while their format modified, like so:

    images/ok-button.gif => images/buttons/ok.png
    images/cancel-button.gif => images/buttons/cancel.png

This suggests that we might be able to look around to see what other rename src/target candidate files there are, so that we can figure out if there is a common pattern (i.e. in the above example, "patsubst images/%-button.gif,images/buttons/%.png" is what is going on). If we find such a pattern, we can base the assignment of "basename similarity bonus" on that pattern.