Re: "git-diff-tree -R A B == git-diff-tree B A"?

From: Junio C Hamano <junkio@cox.net>
Date: May 20, 2005, 15:29 UTC
Message-ID: <7v64xdvru5.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <Pine.LNX.4.58.0505200806150.2206@ppc970.osdl.org>

>>>>> "LT" == Linus Torvalds <torvalds@osdl.org> writes:

LT> On Fri, 20 May 2005, Junio C Hamano wrote:

Show 20 quoted lines

>> 
>> I was preparing a set of tests for diff family because I wanted
>> to have something that catches screwups I am going to inflict
>> upon them during the coming couple of days.  One of the tests
>> accidentally found out that the above is not true in the current
>> implementation.  Just an excerpt of relevant lines [*1*]:
>> 
>> $ git-diff-tree -r $tree_B $tree_A
>> 
>> +100644 blob 7e426fb079479fd67f6d81f984e4ec649a44bc25 AN
>> +100644 blob 68a6d8b91da11045cf4aa3a5ab9f2a781c701249 DF/DF
>> -100644 blob 71420ab81e254145d26d6fc0cddee64c1acd4787 DF
>> -100644 blob 3c4d8de5fbad08572bab8e10eef8dbb264cf0231 DM
>> 
>> $ git-diff-tree -R $tree_A $tree_B
>> 
>> +100644 blob 7e426fb079479fd67f6d81f984e4ec649a44bc25 AN
>> -100644 blob 71420ab81e254145d26d6fc0cddee64c1acd4787 DF
>> +100644 blob 68a6d8b91da11045cf4aa3a5ab9f2a781c701249 DF/DF
>> -100644 blob 3c4d8de5fbad08572bab8e10eef8dbb264cf0231 DM

LT> Ahh.. "diff-tree" uses the wrong algorithm for selecting name ordering.

LT> It thinks that "DF" and "DF/" sort equally because it just looks at the LT> name, not the type. So then, becuse the names sort the same, it will sort LT> them according to where they come from, and you get the behaviour you see.

LT> It doesn't really matter, but you're right, I should fix it to be LT> consistent.

Don't bother.  I already have a fix with the test case.