Re: [RFC] use typechange as rename source
Jeff King <peff@peff.net> writes:
Show 9 quoted lines
>> In your test case, the "new" symlink won't have any similar symlink that
>> is removed from the preimage, so registering it as a rename destination
>> would not make a difference (it will say "no match found, so create this
>> as usual"), but I am not convinced if that would work well in general.
>
> I don't know that it makes a difference. We are impacting only a
> 'typechange', which implies that we have a filepair in which both p->one
> and p->two are valid; thus, the current code doesn't use it as a rename
> dst at all.
I think it does make a difference, if you have a cross rename that swaps:
$ ls -F foo bar
bar foo@
$ mv foo tmp; mv bar foo; mv tmp bar
$ ls -F foo bar
bar@ fooThe attached patch does not automatically break a filepair that is a typechange, so the new t4023 test asks for diffcore-break with -B explicitly.
I suspect your patch alone would not pass t4023 (with or without -B).
We may want to do the autobreak in diffcore-rename even when -B is not in effect on top of this patch, but that is a separate topic.
-- >8 --
Subject: [PATCH] rename: Break filepairs with different types.
When we consider if a path has been totally rewritten, we did not touch changes from symlinks to files or vice versa. But a change that modifies even the type of a blob surely should count as a complete rewrite.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
cache.h | 7 +++
diffcore-break.c | 7 ++-
t/t4023-diff-rename-typechange.sh | 86 +++++++++++++++++++++++++++++++++++++
tree-walk.h | 7 ---
4 files changed, 97 insertions(+), 10 deletions(-)
create mode 100755 t/t4023-diff-rename-typechange.sh
diff --git a/cache.h b/cache.h
index aaa135b..d0e7a71 100644
--- a/cache.h
+++ b/cache.h
@@ -192,6 +192,13 @@ enum object_type {
OBJ_MAX,
};
+static inline enum object_type object_type(unsigned int mode)
+{
+ return S_ISDIR(mode) ? OBJ_TREE :
+ S_ISGITLINK(mode) ? OBJ_COMMIT :
+ OBJ_BLOB;
+}
+
#define GIT_DIR_ENVIRONMENT "GIT_DIR"
#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
diff --git a/diffcore-break.c b/diffcore-break.c
index c71a226..69afc07 100644
--- a/diffcore-break.c
+++ b/diffcore-break.c
@@ -52,8 +52,8 @@ static int should_break(struct diff_filespec *src,
* is the default.
*/
- if (!S_ISREG(src->mode) || !S_ISREG(dst->mode))
- return 0; /* leave symlink rename alone */
+ if (object_type(src->mode) != object_type(dst->mode))
+ return 1; /* even their types are different */
if (src->sha1_valid && dst->sha1_valid &&
!hashcmp(src->sha1, dst->sha1))
diff --git a/t/t4023-diff-rename-typechange.sh b/t/t4023-diff-rename-typechange.sh
new file mode 100755
index 0000000..255604e
--- /dev/null
+++ b/t/t4023-diff-rename-typechange.sh
@@ -0,0 +1,86 @@
+#!/bin/sh
+
+test_description='typechange rename detection'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+
+ rm -f foo bar &&
+ cat ../../COPYING >foo &&
+ ln -s linklink bar &&
+ git add foo bar &&
+ git commit -a -m Initial &&
+ git tag one &&
+
+ rm -f foo bar &&
+ cat ../../COPYING >bar &&
+ ln -s linklink foo &&
+ git add foo bar &&
+ git commit -a -m Second &&
+ git tag two &&
+
+ rm -f foo bar &&
+ cat ../../COPYING >foo &&
+ git add foo &&
+ git commit -a -m Third &&
+ git tag three &&
+
+ mv foo bar &&
+ ln -s linklink foo &&
+ git add foo bar &&
+ git commit -a -m Fourth &&
+ git tag four &&
+
+ # This is purely for sanity check
+
+ rm -f foo bar &&
+ cat ../../COPYING >foo &&
+ cat ../../Makefile >bar &&
+ git add foo bar &&
+ git commit -a -m Fifth &&
+ git tag five &&
+
+ rm -f foo bar &&
+ cat ../../Makefile >foo &&
+ cat ../../COPYING >bar &&
+ git add foo bar &&
+ git commit -a -m Sixth &&
+ git tag six
+
+'
+
+test_expect_success 'cross renames to be detected for regular files' '
+
+ git diff-tree five six -r --name-status -B -M | sort >actual &&
+ {
+ echo "R100 foo bar"
+ echo "R100 bar foo"
+ } | sort >expect &&
+ diff -u expect actual
+
+'
+
+test_expect_success 'cross renames to be detected for typechange' '
+
+ git diff-tree one two -r --name-status -B -M | sort >actual &&
+ {
+ echo "R100 foo bar"
+ echo "R100 bar foo"
+ } | sort >expect &&
+ diff -u expect actual
+
+'
+
+test_expect_success 'moves and renames' '
+
+ git diff-tree three four -r --name-status -B -M | sort >actual &&
+ {
+ echo "R100 foo bar"
+ echo "T100 foo"
+ } | sort >expect &&
+ diff -u expect actual
+
+'
+
+test_done
diff --git a/tree-walk.h b/tree-walk.h
index 903a7b0..db0fbdc 100644
--- a/tree-walk.h
+++ b/tree-walk.h
@@ -7,13 +7,6 @@ struct name_entry {
unsigned int mode;
};
-static inline enum object_type object_type(unsigned int mode)
-{
- return S_ISDIR(mode) ? OBJ_TREE :
- S_ISGITLINK(mode) ? OBJ_COMMIT :
- OBJ_BLOB;
-}
-
struct tree_desc {
const void *buffer;
struct name_entry entry;
--
1.5.3.6.2090.g4ece0
Jeff King