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Author SHA1 Message Date
Junio C Hamano 1335d76e45 merge: avoid "safer crlf" during recording of merge results
When merge_recursive() decides what the correct blob object merge
result for a path should be, it uses update_file_flags() helper
function to write it out to a working tree file and then calls
add_cacheinfo().  The add_cacheinfo() function in turn calls
make_cache_entry() to create a new cache entry to replace the
higher-stage entries for the path that represents the conflict.

The make_cache_entry() function calls refresh_cache_entry() to fill
in the cached stat information.  To mark a cache entry as
up-to-date, the data is re-read from the file in the working tree,
and goes through convert_to_git() conversion to be compared with the
blob object name the new cache entry records.

It is important to note that this happens while the higher-stage
entries, which are going to be replaced with the new entry, are
still in the index.  Unfortunately, the convert_to_git() conversion
has a misguided "safer crlf" mechanism baked in, and looks at the
existing cache entry for the path to decide how to convert the
contents in the working tree file.  If our side (i.e. stage#2)
records a text blob with CRLF in it, even when the system is
configured to record LF in blobs and convert them to CRLF upon
checkout (and back to LF upon checkin), the "safer crlf" mechanism
stops us doing so.

This especially poses a problem during a renormalizing merge, where
the merge result for the path is computed by first "normalizing" the
blobs involved in the merge by using convert_to_working_tree()
followed by convert_to_git() with "safer crlf" disabled.  The merge
result that is computed correctly and fed to add_cacheinfo() via
update_file_flags() does _not_ match what refresh_cache_entry() sees
by converting the working tree file via convert_to_git().

We can work this around by not refreshing the new cache entry in
make_cache_entry() called by add_cacheinfo().  After add_cacheinfo()
adds the new entry, we can call refresh_cache_entry() on that,
knowing that addition of this new cache entry would have removed the
stale cache entries that had CRLF in stage #2 that were carried over
before the renormalizing merge started and will not interfere with
the correct recording of the result.

The test update was taken from a series by Torsten Bögershausen
that attempted to fix this with a different approach.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reviewed-by: Torsten Bögershausen <tboegi@web.de>
2016-07-12 13:06:43 -07:00
Torsten Bögershausen 6523728499 convert: unify the "auto" handling of CRLF
Before this change,
$ echo "* text=auto" >.gitattributes
$ echo "* eol=crlf" >>.gitattributes

would have the same effect as
$ echo "* text" >.gitattributes
$ git config core.eol crlf

Since the 'eol' attribute had higher priority than 'text=auto', this may
corrupt binary files and is not what most users expect to happen.

Make the 'eol' attribute to obey 'text=auto' and now
$ echo "* text=auto" >.gitattributes
$ echo "* eol=crlf" >>.gitattributes
behaves the same as
$ echo "* text=auto" >.gitattributes
$ git config core.eol crlf

In other words,
$ echo "* text=auto eol=crlf" >.gitattributes
has the same effect as
$ git config core.autocrlf true

and
$ echo "* text=auto eol=lf" >.gitattributes
has the same effect as
$ git config core.autocrlf input

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-06 11:53:51 -07:00
Brice Lambson 5f4e02e517 MinGW: update tests to handle a native eol of crlf
Some of the tests were written with the assumption that the native
eol would always be lf. After defining NATIVE_CRLF on MinGW, these
tests began failing.  This change will update the tests to also
handle a native eol of crlf.

Signed-off-by: Brice Lambson <bricelam@live.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-02 12:09:40 -07:00
Ramsay Jones a31d066524 t6038-*.sh: Pass the -b (--binary) option to sed on cygwin
The tests using the fuzz_conflict helper function (tests 5-6)
fail on cygwin in the same way they used to on MinGW, prior
to commit ca02ad3. The solution is also the same; passing the
-b (--binary) option to sed, using the SED_OPTIONS variable.
We introduce a new prerequisite SED_STRIPS_CR to use in the
conditional initialisation of SED_OPTIONS, rather than MINGW.
The new prerequisite is set in test-lib.sh for both MinGW and
Cygwin.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-08 23:36:37 -08:00
Eric Sunshine ca02ad3447 Side-step sed line-ending "corruption" leading to t6038 failure.
By default, MSYS sed throws away CR from CRLF line-endings.  Tests
t6038.5 and t6038.6 employ sed to normalize conflict output of git-merge
for validation purposes.  These tests expect CRLF line-endings to be
present in the normalized output of git-merge, and thus fail when sed
undesirably removes CR.  Fix by employing sed's -b/--binary switch to
suppress its default behavior of dropping CR characters.

Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
2010-10-03 23:29:19 +01:00
Jonathan Nieder beeeb45493 t6038 (merge.renormalize): check that it can be turned off
An unusual sort of person (not me) may even enjoy the conflicts
from line-ending changes.  But more importantly, it is useful to
document that behavior so we can more easily notice if it changes
in an uncontrolled way while no one is watching.

Cc: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:20:00 -07:00
Jonathan Nieder d347cee4de t6038 (merge.renormalize): try checkout -m and cherry-pick
checkout -m and cherry-pick have not been wired up to respect
merge.renormalize, but a naïve user would not know that.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:20:00 -07:00
Jonathan Nieder 18acb30ee4 t6038 (merge.renormalize): style nitpicks
Some tweaks to simplify adding and running tests.

 - Use test_tick for predictable, sort of realistic commit dates;

 - Use test_cmp as "test_cmp expected actual" --- some crazy
   content that was not expected should cause the test to fail;

 - Remove and re-add all files at the start of each test so the
   worktree is easier to think about;

 - Avoid using cat where not necessary for clarity.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:20:00 -07:00
Eyvind Bernhardsen 331a1838b2 Try normalizing files to avoid delete/modify conflicts when merging
If a file is modified due to normalization on one branch, and deleted on
another, a merge of the two branches will result in a delete/modify
conflict for that file even if it is otherwise unchanged.

Try to avoid the conflict by normalizing and comparing the "base" file
and the modified file when their sha1s differ.  If they compare equal,
the file is considered unmodified and is deleted.

Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-07-02 15:44:34 -07:00
Eyvind Bernhardsen f217f0e86d Avoid conflicts when merging branches with mixed normalization
Currently, merging across changes in line ending normalization is
painful since files containing CRLF will conflict with normalized files,
even if the only difference between the two versions is the line
endings.  Additionally, any "real" merge conflicts that exist are
obscured because every line in the file has a conflict.

Assume you start out with a repo that has a lot of text files with CRLF
checked in (A):

      o---C
     /     \
    A---B---D

B: Add "* text=auto" to .gitattributes and normalize all files to
   LF-only

C: Modify some of the text files

D: Try to merge C

You will get a ridiculous number of LF/CRLF conflicts when trying to
merge C into D, since the repository contents for C are "wrong" wrt the
new .gitattributes file.

Fix ll-merge so that the "base", "theirs" and "ours" stages are passed
through convert_to_worktree() and convert_to_git() before a three-way
merge.  This ensures that all three stages are normalized in the same
way, removing from consideration differences that are only due to
normalization.

This feature is optional for now since it changes a low-level mechanism
and is not necessary for the majority of users.  The "merge.renormalize"
config variable enables it.

Signed-off-by: Eyvind Bernhardsen <eyvind.bernhardsen@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-07-02 15:43:15 -07:00