Re: svn diff produces a patch which does not reapply cleanly

On Wed, Jan 7, 2009 at 10:07 AM, Stefan Kueng <tortoisesvn_at_gmail.com> wrote:
> David Ellingsworth wrote:
>> On Wed, Jan 7, 2009 at 11:26 AM, Stefan Küng <tortoisesvn_at_gmail.com> wrote:
>>> Daniel Shahaf wrote:
>>>> David Ellingsworth wrote on Tue, 6 Jan 2009 at 19:57 -0500:
>>>>> While using TortoiseSVN 1.5.6 build 14908, I encountered an error
>>>>> while trying to apply a patch with TortoiseMerge that was previously
>>>>> created using TortoiseSVN's "Create Patch" feature. While I was unable
>>>>> to apply the patch with TortoiseMerge, I did succeed while using the
>>>>> standard patch command, but not without any fuzz.
>>>>>
>>>>> The reply to the issue I posted on TortioseSVN"s user mailing list
>>>>> indicates this is an error in svn's core since the patch generated is
>>>>> equivalent to "svn diff file > patchfile". I have verified this using
>>>>> svn client 1.5.1 and 1.5.5.
>>>>>
>>>>> Attached are some files I created which are capable of reliably
>>>>> reproducing the problem. The files are as follows: the original
>>>>> file(test.txt), the updated file(test_v2.txt), and the associated
>>>>> patch file generated from svn diff(test.patch).
>>>>>
>>>> What *exactly* should we do with these three files to reproduce the error?
>>>> (If you can package the answer in script (or transcript) form, that's
>>>> best.) I tried
>>>>
>>>> svn add wc1\trunk\test.txt
>>>> svn commit wc1 -m "add"
>>>> rm -f wc1\trunk\test.txt
>>>> cp wc1\trunk\test_v2.txt wc1\trunk\test.txt
>>>> svn diff wc1 > out
>>>> vim -Nu NONE -c "%s/\r//" -c "wq ++ff=dos" out
>>>> svn revert wc1\trunk\test.txt
>>>> patch -d wc1\trunk < out
>>>> diff -u wc1\trunk\test*.txt
>>>>
>>>> but it didn't cause any error message, and the 'diff -u' at the end also
>>>> found no differences (the expected result). Results are the same with
>>>> both 1.5 and trunk.
>>> Try
>>>
>>> svn add wc1\trunk\test.txt
>>> svn commit wc1 -m "add"
>>> cp test_v2.txt wc1\trunk\test.txt
>>> svn diff wc1 > out
>>> svn revert wc1\trunk\test.txt
>>> patch -d wc1\trunk < out
>>>
>>> Stefan
>>>
>>
>> Output is as follows, I don't have a trunk directory so it's been excluded:
>>
>> $ svn add wc1\test.txt
>> A wc1\test.txt
>>
>> $ svn commit wc1 -m "add"
>> Adding wc1\test.txt
>> Transmitting file data .
>> Committed revision 1.
>>
>> $ cp test_v2.txt wc1\test.txt
>>
>> $ svn diff wc1 > out
>>
>> $ svn revert wc1\test.txt
>> Reverted 'wc1\test.txt'
>>
>> $ patch -d wc1 < out
>> patching file 'test.txt'
>> Hunk #2 succeeded at 7 (offset 2 lines)
>
> sure, the patch can be applied, but not cleanly - 'offset 2 lines'.
> The patch should be applied cleanly, without any offset.
>
> I haven't found any clear docs on how a patch file really is defined,
> but from what I think is wrong:
>
> The chunk info line
> @@ -2,9 +5,9 @@
> is wrong. AFAIK the first number (-2) is the line number where removing
> starts, the second one the number of lines to remove (including context
> lines), the third one (5) the line number where adding starts and the
> fourth (9) the number of lines to add (also including context lines).
>
> Now, in 1.4.x, the diff would have the start line numbers adjusted. The
> first chunk is always correct, but now (>= 1.5.x) the line numbers are
> always in reference to the original file. Before those lines were
> adjusted: if a chunk before added lines or removed lines, the 'start'
> lines of the following chunks would take that into account.
>
> Does anyone know if (and where) the patch file format is documented?
> Because I may be completely wrong here - I've implemented the patch
> functionality in TortoiseMerge completely by reverse engineering the
> format...

I get the same patch with 1.4.x and ~trunk (with that line), FWIW.
You get something different with 1.4.x?

--dave

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