From: Junio C Hamano <gitster@pobox•com>
To: git@vger•kernel.org
Subject: [PATCH] diff -B -M: fix output for "copy and then rewrite" case
Date: Thu, 23 Oct 2014 16:34:40 -0700 [thread overview]
Message-ID: <xmqqoat2gy27.fsf@gitster.dls.corp.google.com> (raw)
Starting from a single file, A, if you create B as a copy of A (and
possibly make some edit) and then make extensive change to A, you
will see:
$ git diff -C --name-status
C89 A B
M A
which is expected. However, if you ask the same question in a
different way, you see this:
$ git diff -B -M --name-status
R89 A B
M100 A
telling us that A was rename-edited into B (as if "A will no longer
exist as the result") and at the same time A itself was extensively
edited.
In this case, because the resulting tree still does have file A
(even if it has contents vastly different from the original), we
should use "C"opy, not "R"ename, to avoid hinting that A somehow
goes away.
Two existing tests were depending on the wrong behaviour, and fixed.
Signed-off-by: Junio C Hamano <gitster@pobox•com>
---
diffcore-break.c | 7 +++++++
t/t4008-diff-break-rewrite.sh | 4 ++--
t/t4023-diff-rename-typechange.sh | 3 ++-
3 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/diffcore-break.c b/diffcore-break.c
index 1d9e530..5473493 100644
--- a/diffcore-break.c
+++ b/diffcore-break.c
@@ -246,6 +246,13 @@ static void merge_broken(struct diff_filepair *p,
dp = diff_queue(outq, d->one, c->two);
dp->score = p->score;
+ /*
+ * We will be one extra user of the same src side of the
+ * broken pair, if it was used as the rename source for other
+ * paths elsewhere. Increment to mark that the path stays
+ * in the resulting tree.
+ */
+ d->one->rename_used++;
diff_free_filespec_data(d->two);
diff_free_filespec_data(c->one);
free(d);
diff --git a/t/t4008-diff-break-rewrite.sh b/t/t4008-diff-break-rewrite.sh
index 27e98a8..8920464 100755
--- a/t/t4008-diff-break-rewrite.sh
+++ b/t/t4008-diff-break-rewrite.sh
@@ -123,10 +123,10 @@ test_expect_success \
'git diff-index -B -M "$tree" >current'
# file0 changed from regular to symlink. file1 is very close to the preimage of file0.
-# because we break file0, file1 can become a rename of it.
+# the change does not make file0 disappear, so file1 is denoted as a copy of file0
cat >expected <<\EOF
:100644 120000 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 67be421f88824578857624f7b3dc75e99a8a1481 T file0
-:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 R file0 file1
+:100644 100644 6ff87c4664981e4397625791c8ea3bbb5f2279a3 f5deac7be59e7eeab8657fd9ae706fd6a57daed2 C file0 file1
EOF
test_expect_success \
diff --git a/t/t4023-diff-rename-typechange.sh b/t/t4023-diff-rename-typechange.sh
index 55d549f..8c98237 100755
--- a/t/t4023-diff-rename-typechange.sh
+++ b/t/t4023-diff-rename-typechange.sh
@@ -76,7 +76,8 @@ test_expect_success 'moves and renames' '
git diff-tree three four -r --name-status -B -M | sort >actual &&
{
- echo "R100 foo bar"
+ # see -B -M (#6) in t4008
+ echo "C100 foo bar"
echo "T100 foo"
} | sort >expect &&
test_cmp expect actual
--
2.1.2-595-g1568c45
reply other threads:[~2014-10-23 23:34 UTC|newest]
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