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view tests/test-no-symlinks.t @ 32979:66117dae87f9
patch: rewrite reversehunks (issue5337)
The old reversehunks code accesses "crecord.uihunk._hunk", which is the raw
recordhunk without crecord selection information, therefore "revert -i"
cannot revert individual lines, aka. issue5337.
The patch rewrites related logic to return the right reverse hunk for
revert. Namely,
1. "fromline" and "toline" are correctly swapped [1]
2. crecord.uihunk generates a correct reverse hunk [2]
Besides, reversehunks(hunks) will no longer modify its input "hunks", which
is more expected.
[1]: To explain why "fromline" and "toline" need to be swapped, take the
following example:
$ cat > a <<EOF
> 1
> 2
> 3
> 4
> EOF
$ cat > b <<EOF
> 2
> 3
> 5
> EOF
$ diff a b
1d0 <---- "1" is "fromline" and "0" is "toline"
< 1 and they are swapped if diff from the reversed direction
4c3 |
< 4 |
--- |
> 5 |
|
$ diff b a |
0a1 <---------+
> 1
3c4 <---- also "4c3" gets swapped to "3c4"
< 5
---
> 4
[2]: This is a bit tricky.
For example, given a file which is empty in working parent but has 3 lines
in working copy, and the user selection:
select hunk to discard
[x] +1
[ ] +2
[x] +3
The user intent is to drop "1" and "3" in working copy but keep "2", so the
reverse patch would be something like:
-1
2 (2 is a "context line")
-3
We cannot just take all selected lines and swap "-" and "+", which will be:
-1
-3
That patch won't apply because of "2". So the correct way is to insert "2"
as a "context line" by inserting it first then deleting it:
-2
+2
Therefore, the correct revert patch is:
-1
-2
+2
-3
It could be reordered to look more like a common diff hunk:
-1
-2
-3
+2
Note: It's possible to return multiple hunks so there won't be lines like
"-2", "+2". But the current implementation is much simpler.
For deletions, like the working parent has "1\n2\n3\n" and it was changed to
empty in working copy:
select hunk to discard
[x] -1
[ ] -2
[x] -3
The user intent is to drop the deletion of 1 and 3 (in other words, keep
those lines), but still delete "2".
The reverse patch is meant to be applied to working copy which is empty.
So the patch would be:
+1
+3
That is to say, there is no need to special handle the unselected "2" like
the above insertion case.
author | Jun Wu <quark@fb.com> |
---|---|
date | Tue, 20 Jun 2017 23:22:38 -0700 |
parents | 7a9cbb315d84 |
children | 2d49d2eb1ff2 |
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#require no-symlink # The following script was used to create the bundle: # # hg init symlinks # cd symlinks # echo a > a # mkdir d # echo b > d/b # ln -s a a.lnk # ln -s d/b d/b.lnk # hg ci -Am t # hg bundle --base null ../test-no-symlinks.hg Extract a symlink on a platform not supporting them $ hg init t $ cd t $ hg pull -q "$TESTDIR/bundles/test-no-symlinks.hg" $ hg update 4 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cat a.lnk && echo a $ cat d/b.lnk && echo d/b Copy a symlink and move another $ hg copy a.lnk d/a2.lnk $ hg mv d/b.lnk b2.lnk $ hg ci -Am copy $ cat d/a2.lnk && echo a $ cat b2.lnk && echo d/b Bundle and extract again $ hg bundle --base null ../symlinks.hg 2 changesets found $ cd .. $ hg init t2 $ cd t2 $ hg pull ../symlinks.hg pulling from ../symlinks.hg requesting all changes adding changesets adding manifests adding file changes added 2 changesets with 6 changes to 6 files (run 'hg update' to get a working copy) $ hg update 5 files updated, 0 files merged, 0 files removed, 0 files unresolved $ cat a.lnk && echo a $ cat d/a2.lnk && echo a $ cat b2.lnk && echo d/b