When comparing the index and the working tree to show which paths are
new, and comparing the tree recorded in the HEAD and the index to see if
committing the contents recorded in the index would result in an empty
commit, we would want the former comparison to say "these are new paths"
and the latter to say "there is no change" for paths that are marked as
intent-to-add.
We made a similar attempt at d95d728a ("diff-lib.c: adjust position of
i-t-a entries in diff", 2015-03-16), which redefined the semantics of
these two comparison modes globally, which was a disaster and had to be
reverted at 78cc1a54 ("Revert "diff-lib.c: adjust position of i-t-a
entries in diff"", 2015-06-23).
To make sure we do not repeat the same mistake, introduce a new internal
diffopt option so that this different semantics can be asked for only by
callers that ask it, while making sure other unaudited callers will get
the same comparison result.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a subdirectory contains nothing but i-t-a entries, we generate an
empty tree object and add it to its parent tree. Which is wrong. Such
a subdirectory should not be added.
Note that this has a cascading effect. If subdir 'a/b/c' contains
nothing but i-t-a entries, we ignore it. But then if 'a/b' contains
only (the non-existing) 'a/b/c', then we should ignore 'a/b' while
building 'a' too. And it goes all the way up to top directory.
Noticed-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 3cf773e (cache-tree: fix writing cache-tree when CE_REMOVE is
present - 2012-12-16) skips i-t-a entries when building trees objects
from the index. Unfortunately it may skip too much.
The code in question checks if an entry is an i-t-a one, then no tree
entry will be written. But it does not take into account that
directories can also be written with the same code. Suppose we have
this in the index.
a-file
subdir/file1
subdir/file2
subdir/file3
the-last-file
We write an entry for a-file as normal and move on to subdir/file1,
where we realize the entry name for this level is simply just
"subdir", write down an entry for "subdir" then jump three items ahead
to the-last-file.
That is what happens normally when the first file in subdir is not an
i-t-a entry. If subdir/file1 is an i-t-a, because of the broken
condition in this code, we still think "subdir" is an i-t-a file and
not writing "subdir" down and jump to the-last-file. The result tree
now only has two items: a-file and the-last-file. subdir should be
there too (even though it only records two sub-entries, file2 and
file3).
If the i-t-a entry is subdir/file2 or subdir/file3, this is not a
problem because we jump over them anyway. Which may explain why the
bug is hidden for nearly four years.
Fix it by making sure we only skip i-t-a entries when the entry in
question is actual an index entry, not a directory.
Reported-by: Yuri Kanivetsky <yuri.kanivetsky@gmail.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This reverts commit d95d728aba.
It turns out that many other commands that need to interact with the
result of running diff-files and diff-index, e.g. "git apply", "git
rm", etc., need to be adjusted to the new world order it brings in.
For example, it would break this sequence to correct a whitespace
breakage in the parts you changed:
git add -N file
git diff --cached file | git apply --cached --whitespace=fix
git checkout file
In the old world order, "diff" showed a patch to modify an existing
empty file by adding its full contents, and "apply" updated the
index by modifying the existing empty blob (which is what an
Intent-to-Add entry records in the index) with that patch.
In the new world order, "diff" shows a patch to create a new file
with its full contents, but because "apply" thinks that the i-t-a
entry already exists in the index, it refused to accept a creation.
Adjusting "apply" to this new world order is easy, but we need to
assess the extent of the damage to the rest of the system the new
world order brought in before going forward and adjust them all,
after which we can resurrect the commit being reverted here.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Entries added by "git add -N" are reminder for the user so that they
don't forget to add them before committing. These entries appear in
the index even though they are not real. Their presence in the index
leads to a confusing "git status" like this:
On branch master
Changes to be committed:
new file: foo
Changes not staged for commit:
modified: foo
If you do a "git commit", "foo" will not be included even though
"status" reports it as "to be committed". This patch changes the
output to become
On branch master
Changes not staged for commit:
new file: foo
no changes added to commit
The two hunks in diff-lib.c adjust "diff-index" and "diff-files" so
that i-t-a entries appear as new files in diff-files and nothing in
diff-index.
Due to this change, diff-files may start to report "new files" for the
first time. "add -u" needs to be told about this or it will die in
denial, screaming "new files can't exist! Reality is wrong." Luckily,
it's the only one among run_diff_files() callers that needs fixing.
Now in the new world order, a hierarchy in the index that contain
i-t-a paths is written out as a tree object as if these i-t-a
entries do not exist, and comparing the index with such a tree
object that would result from writing out the hierarchy will result
in no difference. Update a test in t2203 that expected the i-t-a
entries to appear as "added to the index" in the comparison to
instead expect no output.
An earlier change eec3e7e4 (cache-tree: invalidate i-t-a paths after
generating trees, 2012-12-16) becomes an unnecessary pessimization
in the new world order---a cache-tree in the index that corresponds
to a hierarchy with i-t-a paths can now be marked as valid and
record the object name of the tree that results from writing a tree
object out of that hierarchy, as it will compare equal to that tree.
Reverting the commit is left for the future, though, as it is purely
a performance issue and no longer affects correctness.
Helped-by: Michael J Gruber <git@drmicha.warpmail.net>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Intent-to-add entries used to forbid writing trees so it was not a
problem. After commit 3f6d56d (commit: ignore intent-to-add entries
instead of refusing - 2012-02-07), we can generate trees from an index
with i-t-a entries.
However, the commit forgets to invalidate all paths leading to i-t-a
entries. With fully valid cache-tree (e.g. after commit or
write-tree), diff operations may prefer cache-tree to index and not
see i-t-a entries in the index, because cache-tree does not have them.
Reported-by: Jonathon Mah <me@JonathonMah.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Originally, "git add -N" was introduced to help users from forgetting to
add new files to the index before they ran "git commit -a". As an attempt
to help them further so that they do not forget to say "-a", "git commit"
to commit the index as-is was taught to error out, reminding the user that
they may have forgotten to add the final contents of the paths before
running the command.
This turned out to be a false "safety" that is useless. If the user made
changes to already tracked paths and paths added with "git add -N", and
then ran "git add" to register the final contents of the paths added with
"git add -N", "git commit" will happily create a commit out of the index,
without including the local changes made to the already tracked paths. It
was not a useful "safety" measure to prevent "forgetful" mistakes from
happening.
It turns out that this behaviour is not just a useless false "safety", but
actively hurts use cases of "git add -N" that were discovered later and
have become popular, namely, to tell Git to be aware of these paths added
by "git add -N", so that commands like "git status" and "git diff" would
include them in their output, even though the user is not interested in
including them in the next commit they are going to make.
Fix this ancient UI mistake, and instead make a commit from the index
ignoring the paths added by "git add -N" without adding real contents.
Based on the work by Nguyễn Thái Ngọc Duy, and helped by injection of
sanity from Jonathan Nieder and others on the Git mailing list.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add commit message to avoid commit's aborting due to the lack of
commit message, not because there are INTENT_TO_ADD entries in index.
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Writing a tree out of an index with an "intent to add" entry is blocked.
This implies that you cannot "git commit" from such a state; however you
can still do "git commit -a" or "git commit $that_path".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This adds "--intent-to-add" option to "git add". This is to let the
system know that you will tell it the final contents to be staged later,
iow, just be aware of the presense of the path with the type of the blob
for now. It is implemented by staging an empty blob as the content.
With this sequence:
$ git reset --hard
$ edit newfile
$ git add -N newfile
$ edit newfile oldfile
$ git diff
the diff will show all changes relative to the current commit. Then you
can do:
$ git commit -a ;# commit everything
or
$ git commit oldfile ;# only oldfile, newfile not yet added
to pretend you are working with an index-free system like CVS.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
