git/list[1] front-page[2] threads[3] people[4] search[5] about
 

Re: end-of-line diff checkout direction dependence problem

From
TVThomas Vieten <tvie@ivision.de>
Date
Jul 2, 2015, 14:00 UTC
Message-ID
<559543E9.5040706@ivision.de>
In-Reply-To
<5593F73E.60305@ivision.de>
Answers and new response below.
Thomas Vieten wrote:
Show 83 quoted lines
> On 2015-06-30 16.12, Thomas Vieten wrote:
>> We face a very inconvenient problem with end-of-line diffs which are 
>> not "real".
>> We know the end-of-line problem very well as we thought.
>> But now we found a new phenomenon and nobody mentioning it.
>>
>> Consider the following repository structure:
>>
>>           -----------|----|------------->branch1
>>         /
>> master
>>         \
>> ----------|-------|---------|--------------->branch2
>>
>> The branches are based on master/head.
>> We just consider one branch here, e.g. branch1 .
>>
>> Working with the head of branch1 gives no problems. No end-of-line 
>> diffs.
>> Also going back in the direction of master - no problems.
>> Only in the case if we do a checkout from branch1 to master, then
>> all of a sudden end-of-line diffs appear.
>> The files might be changed, but the end-of-line attributes in 
>> gitattributes are
>> not changed in the branch.
>>
>> It seems to be the case that since the last change to the files which 
>> pop up
>> with eol differences, gittattributes where changed and touch their 
>> extensions.
>>
>> With the operation
>>
>> git ls-files -z | xargs -0 rm -f  # delete all the files of this 
>> version - here
>> master/head
>> git reset --hard                  # force checkout of master/head and 
>> reset index
>>
>> The problem disappears! No eol problems anymore. Something like a 
>> brute force
>> checkout.
>>
>> Also checking out versions in the direction of branch1 give never 
>> end-of-line
>> diffs.
>>
>> What has changed somewhen are the gitattributes.
>>
>> We estimate that this becomes a problem when applying the diffs from 
>> branch1 in
>> the direction of
>> the master. Finally then the diffs result in a different state from 
>> the master.
>>
>> But when the master is checked out freshly, this difference does not 
>> appear.
>>
>> Very, very annoying.
>>
>> We check now every time when these end-of-line diffs appear, if they 
>> are really
>> end of line diffs
>>
>> git diff --ignore-space-at-eol
>>
>> and then try the procedure above.
>>
>> But to have a dependence from the direction of the checkout is 
>> somewhat irritating.
>>
>> If this is not a bug - then how to avoid it ?
>>
>> bye for now
>>
>> Thomas
>>
> The things which are described don't sound unfamilar.
> First some questions:
> Which Git/OS are you running on ?
>
> CYGWIN ?
> Git-for-Windows ?

git version 1.9.2.msysgit.0 +tortoisegit, for viewing and conflicts

> Linux ?
> Other ?
Windows 7 Pro
>
> Which versions ?
> How does your .gitattribute file look like ?
>
see the file attachend to the end of this message
Show 7 quoted lines
> It may be, that you need to "nornalize" your repo:
>
> https://www.kernel.org/pub/software/scm/git/docs/gitattributes.html
> The search for this text
> "When text=auto normalization"
> and follow the instructions:
>

in principle we know all this. What is remarkable that we are able to checkout a version of master which is not consistent with the repo, and more, dependent from the checkout direction (if the direction is the positive or negative history in time). And on the other hand we can checkout a version of master which is in sync with the master.

Normally such conflicts with not normalised repos appear immediately also in positive history direction. And then it is possible to detect them. The other way around - negative history and diffs - it causes a big questionmark.

On the other hand this would lead to the mandatory work flow advice: 
"Always normalize the repository after changes within the gitattributes 
file"
And then: Should this then not be automatically be done somehow in the 
background by git ?
Reasoning: if the "git machine" is causing this behaviour 
systematically, shouldn't the machine itself have compensation, correction?
Depending on your point of view this could be seen as a bug.

There is also a big question open: will normalisation really help ? Because there must be one commit with the new gitattributes and then you normalize. But the "wrong diff" is in the repo and will cause the problem when going back to master in the negative direction. This is how understand it up to now.

But at this point git is complex and we are not really the experts.
best regards
Thomas V.
--------------------------------------------------------------------------------------------------------
.gitattributes
#Set default behaviour, in case users don't have core.autocrlf set.
* text=auto
*.PC                text
*.in                text
*.hex               text
*.inc               text
*.DAT               binary
*.lic               binary
*.chm               binary
*.dat               binary
*.cam               binary
*.cam.new           binary
*.cam.cam           binary
*.am                text
*.cc                text
*.m4                eol=lf
*.exe               binary
*.sys               binary
*.dll               binary
*.cxf               eol=lf
*.vcproj            eol=crlf
*.vcxproj           text
*.vcxproj.filters   text
*.sln               eol=crlf
*.dsp               eol=crlf
*.dsw               eol=crlf
*.sh                text
*.txt               text
*.png               binary
*.jpg               binary
*.tif               binary
*.odt               binary
*.db                binary
*.vsd               binary
*.dbf               binary
*.zip               binary
*.emf               binary
*.psp               binary
*.dot               binary
*.doc               diff=word
*.sql               text
*.vsd               binary
*.sys               binary
*.xls               binary
*.vxd               binary
*.jpg               binary
*.jpeg              binary
*.sch               binary
*.pdf               binary
*.s#*               binary
*.ocx               binary
*.gif               binary
*.gz                binary
*.obj               binary
*.ncb               binary
*.bin               binary
*.bmp               binary
*.cmd               eol=crlf
*.bat               eol=crlf
*.htm               eol=crlf
*.html              eol=crlf
*.dsp               eol=crlf
*.dbf               binary
*.vtg               binary
*.mdb               binary
*.msi               binary
*.cbproj            binary
*.groupproj         binary
*.bdsgroup          binary
*.tgr               binary
*.pbd               binary
*.pbl               binary
*.tag               binary
makefile            text
*.c                 text
*.cpp               text
*.h                 text
*.hpp               text
Previous: Torsten BögershausenNext: Torsten Bögershausen
Message 3 of 4 in “end-of-line diff checkout direction dependence problem”
  1. Thomas VietenJun 30, 2015
  2. Torsten BögershausenJun 30, 2015
  3. Thomas VietenJul 2, 2015
  4. Torsten BögershausenJul 6, 2015

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.