From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 13 Apr 2016 21:12:32 +0000 (-0700)
Subject: Merge branch 'sg/diff-multiple-identical-renames'
X-Git-Tag: v2.9.0-rc0~130
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/26effb8487386e431990905d4eba7e81f1018eda?ds=inline;hp=-c

Merge branch 'sg/diff-multiple-identical-renames'

"git diff -M" used to work better when two originally identical
files A and B got renamed to X/A and X/B by pairing A to X/A and B
to X/B, but this was broken in the 2.0 timeframe.

* sg/diff-multiple-identical-renames:
diffcore: fix iteration order of identical files during rename detection
---

26effb8487386e431990905d4eba7e81f1018eda
diff --combined diffcore-rename.c
index 3b3c1ed535,69fcf77be0..7f03eb5a04
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@@ -340,9 -340,11 +340,11 @@@ static int find_exact_renames(struct di
  	int i, renames = 0;
  	struct hashmap file_table;
  
- 	/* Add all sources to the hash table */
+ 	/* Add all sources to the hash table in reverse order, because
+ 	 * later on they will be retrieved in LIFO order.
+ 	 */
  	hashmap_init(&file_table, NULL, rename_src_nr);
- 	for (i = 0; i < rename_src_nr; i++)
+ 	for (i = rename_src_nr-1; i >= 0; i--)
  		insert_file_table(&file_table, i, rename_src[i].p->one);
  
  	/* Walk the destinations and find best source match */
@@@ -537,7 -539,7 +539,7 @@@ void diffcore_rename(struct diff_option
  				rename_dst_nr * rename_src_nr, 50, 1);
  	}
  
 -	mx = xcalloc(num_create * NUM_CANDIDATE_PER_DST, sizeof(*mx));
 +	mx = xcalloc(st_mult(num_create, NUM_CANDIDATE_PER_DST), sizeof(*mx));
  	for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
  		struct diff_filespec *two = rename_dst[i].two;
  		struct diff_score *m;
diff --combined t/t4001-diff-rename.sh
index c7e58b69a9,ed90c6c6f9..0d1fa45d25
--- a/t/t4001-diff-rename.sh
+++ b/t/t4001-diff-rename.sh
@@@ -9,84 -9,21 +9,84 @@@ test_description='Test rename detectio
  . ./test-lib.sh
  . "$TEST_DIRECTORY"/diff-lib.sh
  
 -echo >path0 'Line 1
 -Line 2
 -Line 3
 -Line 4
 -Line 5
 -Line 6
 -Line 7
 -Line 8
 -Line 9
 -Line 10
 -line 11
 -Line 12
 -Line 13
 -Line 14
 -Line 15
 +test_expect_success 'setup' '
 +	cat >path0 <<-\EOF &&
 +	Line 1
 +	Line 2
 +	Line 3
 +	Line 4
 +	Line 5
 +	Line 6
 +	Line 7
 +	Line 8
 +	Line 9
 +	Line 10
 +	line 11
 +	Line 12
 +	Line 13
 +	Line 14
 +	Line 15
 +	EOF
 +	cat >expected <<-\EOF &&
 +	diff --git a/path0 b/path1
 +	rename from path0
 +	rename to path1
 +	--- a/path0
 +	+++ b/path1
 +	@@ -8,7 +8,7 @@ Line 7
 +	 Line 8
 +	 Line 9
 +	 Line 10
 +	-line 11
 +	+Line 11
 +	 Line 12
 +	 Line 13
 +	 Line 14
 +	EOF
 +	cat >no-rename <<-\EOF
 +	diff --git a/path0 b/path0
 +	deleted file mode 100644
 +	index fdbec44..0000000
 +	--- a/path0
 +	+++ /dev/null
 +	@@ -1,15 +0,0 @@
 +	-Line 1
 +	-Line 2
 +	-Line 3
 +	-Line 4
 +	-Line 5
 +	-Line 6
 +	-Line 7
 +	-Line 8
 +	-Line 9
 +	-Line 10
 +	-line 11
 +	-Line 12
 +	-Line 13
 +	-Line 14
 +	-Line 15
 +	diff --git a/path1 b/path1
 +	new file mode 100644
 +	index 0000000..752c50e
 +	--- /dev/null
 +	+++ b/path1
 +	@@ -0,0 +1,15 @@
 +	+Line 1
 +	+Line 2
 +	+Line 3
 +	+Line 4
 +	+Line 5
 +	+Line 6
 +	+Line 7
 +	+Line 8
 +	+Line 9
 +	+Line 10
 +	+Line 11
 +	+Line 12
 +	+Line 13
 +	+Line 14
 +	+Line 15
 +	EOF
  '
  
  test_expect_success \
@@@ -106,27 -43,27 +106,27 @@@ test_expect_success 
  test_expect_success \
      'git diff-index -p -M after rename and editing.' \
      'git diff-index -p -M $tree >current'
 -cat >expected <<\EOF
 -diff --git a/path0 b/path1
 -rename from path0
 -rename to path1
 ---- a/path0
 -+++ b/path1
 -@@ -8,7 +8,7 @@ Line 7
 - Line 8
 - Line 9
 - Line 10
 --line 11
 -+Line 11
 - Line 12
 - Line 13
 - Line 14
 -EOF
 +
  
  test_expect_success \
      'validate the output.' \
      'compare_diff_patch current expected'
  
 +test_expect_success 'test diff.renames=true' '
 +	git -c diff.renames=true diff --cached $tree >current &&
 +	compare_diff_patch current expected
 +'
 +
 +test_expect_success 'test diff.renames=false' '
 +	git -c diff.renames=false diff --cached $tree >current &&
 +	compare_diff_patch current no-rename
 +'
 +
 +test_expect_success 'test diff.renames unset' '
 +	git diff --cached $tree >current &&
 +	compare_diff_patch current expected
 +'
 +
  test_expect_success 'favour same basenames over different ones' '
  	cp path1 another-path &&
  	git add another-path &&
@@@ -140,6 -77,17 +140,17 @@@ test_expect_success 'favour same basena
  	git show HEAD:path1 | sed "s/15/16/" > subdir/path1 &&
  	git status | test_i18ngrep "renamed: .*path1 -> subdir/path1"'
  
+ test_expect_success 'two files with same basename and same content' '
+ 	git reset --hard &&
+ 	mkdir -p dir/A dir/B &&
+ 	cp path1 dir/A/file &&
+ 	cp path1 dir/B/file &&
+ 	git add dir &&
+ 	git commit -m 2 &&
+ 	git mv dir other-dir &&
+ 	git status | test_i18ngrep "renamed: .*dir/A/file -> other-dir/A/file"
+ '
+ 
  test_expect_success 'setup for many rename source candidates' '
  	git reset --hard &&
  	for i in 0 1 2 3 4 5 6 7 8 9;