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authorJunio C Hamano <junkio@cox.net>2005-06-07 18:36:30 (GMT)
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-07 18:41:51 (GMT)
commitc859600954df4c292ec7c81d7f2f9d0a62b5975b (patch)
tree4c2f1d9fae4deff6e82d0f32f11cc14cd67093c3
parent63aff4fed94355889be98ad44371e29942ff70e4 (diff)
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[PATCH] read-tree: save more user hassles during fast-forward.
This implements the "never lose the current cache information or the work tree state, but favor a successful merge over merge failure" principle in the fast-forward two-tree merge operation. It comes with a set of tests to cover all the cases described in the case matrix found in the new documentation. Signed-off-by: Junio C Hamano <junkio@cox.net> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--Documentation/git-read-tree.txt74
-rw-r--r--read-tree.c49
-rwxr-xr-xt/t1001-read-tree-m-2way.sh281
-rwxr-xr-xt/t1002-read-tree-m-u-2way.sh307
4 files changed, 698 insertions, 13 deletions
diff --git a/Documentation/git-read-tree.txt b/Documentation/git-read-tree.txt
index cbde13d..6440c4b 100644
--- a/Documentation/git-read-tree.txt
+++ b/Documentation/git-read-tree.txt
@@ -53,6 +53,80 @@ the stuff that really changed.
This is used to avoid unnecessary false hits when "git-diff-files" is
run after git-read-tree.
+
+Two Tree Merge
+~~~~~~~~~~~~~~
+
+Typically, this is invoked as "git-read-tree -m $H $M", where $H
+is the head commit of the current repository, and $M is the head
+of a foreign tree, which is simply ahead of $H (i.e. we are in a
+fast forward situation).
+
+When two trees are specified, the user is telling git-read-tree
+the following:
+
+ (1) The current index and work tree is derived from $H, but
+ the user may have local changes in them since $H;
+
+ (2) The user wants to fast-forward to $M.
+
+In this case, the "git-read-tree -m $H $M" command makes sure
+that no local change is lost as the result of this "merge".
+Here are the "carry forward" rules:
+
+ I (index) H M Result
+ -------------------------------------------------------
+ 0 nothing nothing nothing (does not happen)
+ 1 nothing nothing exists use M
+ 2 nothing exists nothing remove path from cache
+ 3 nothing exists exists use M
+
+ clean I==H I==M
+ ------------------
+ 4 yes N/A N/A nothing nothing keep index
+ 5 no N/A N/A nothing nothing keep index
+
+ 6 yes N/A yes nothing exists keep index
+ 7 no N/A yes nothing exists keep index
+ 8 yes N/A no nothing exists fail
+ 9 no N/A no nothing exists fail
+
+ 10 yes yes N/A exists nothing remove path from cache
+ 11 no yes N/A exists nothing fail
+ 12 yes no N/A exists nothing fail
+ 13 no no N/A exists nothing fail
+
+ clean (H=M)
+ ------
+ 14 yes exists exists keep index
+ 15 no exists exists keep index
+
+ clean I==H I==M (H!=M)
+ ------------------
+ 16 yes no no exists exists fail
+ 17 no no no exists exists fail
+ 18 yes no yes exists exists keep index
+ 19 no no yes exists exists keep index
+ 20 yes yes no exists exists use M
+ 21 no yes no exists exists fail
+
+In all "keep index" cases, the cache entry stays as in the
+original index file. If the entry were not up to date,
+git-read-tree keeps the copy in the work tree intact when
+operating under the -u flag.
+
+When this form of git-read-tree returns successfully, you can
+see what "local changes" you made are carried forward by running
+"git-diff-cache --cached $M". Note that this does not
+necessarily match "git-diff-cache --cached $H" would have
+produced before such a two tree merge. This is because of cases
+18 and 19 --- if you already had the changes in $M (e.g. maybe
+you picked it up via e-mail in a patch form), "git-diff-cache
+--cached $H" would have told you about the change before this
+merge, but it would not show in "git-diff-cache --cached $M"
+output after two-tree merge.
+
+
3-Way Merge
~~~~~~~~~~~
Each "index" entry has two bits worth of "stage" state. stage 0 is the
diff --git a/read-tree.c b/read-tree.c
index 2fb27e9..8eb2432 100644
--- a/read-tree.c
+++ b/read-tree.c
@@ -155,28 +155,51 @@ static int threeway_merge(struct cache_entry *stages[4], struct cache_entry **ds
/*
* Two-way merge.
*
- * The rule is:
- * - every current entry has to match the old tree
- * - if the current entry matches the new tree, we leave it
- * as-is. Otherwise we require that it be up-to-date.
+ * The rule is to "carry forward" what is in the index without losing
+ * information across a "fast forward", favoring a successful merge
+ * over a merge failure when it makes sense. For details of the
+ * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
+ *
*/
static int twoway_merge(struct cache_entry **src, struct cache_entry **dst)
{
- struct cache_entry *old = src[0];
- struct cache_entry *a = src[1], *b = src[2];
+ struct cache_entry *current = src[0];
+ struct cache_entry *oldtree = src[1], *newtree = src[2];
if (src[3])
return -1;
- if (old) {
- if (!a || !same(old, a))
+ if (current) {
+ if ((!oldtree && !newtree) || /* 4 and 5 */
+ (!oldtree && newtree &&
+ same(current, newtree)) || /* 6 and 7 */
+ (oldtree && newtree &&
+ same(oldtree, newtree)) || /* 14 and 15 */
+ (oldtree && newtree &&
+ !same(oldtree, newtree) && /* 18 and 19*/
+ same(current, newtree))) {
+ *dst++ = current;
+ return 1;
+ }
+ else if (oldtree && !newtree && same(current, oldtree)) {
+ /* 10 or 11 */
+ verify_uptodate(current);
+ return 0;
+ }
+ else if (oldtree && newtree &&
+ same(current, oldtree) && !same(current, newtree)) {
+ /* 20 or 21 */
+ verify_uptodate(current);
+ return merged_entry(newtree, NULL, dst);
+ }
+ else
+ /* all other failures */
return -1;
}
- if (b)
- return merged_entry(b, old, dst);
- if (old)
- verify_uptodate(old);
- return 0;
+ else if (newtree)
+ return merged_entry(newtree, NULL, dst);
+ else
+ return 0;
}
/*
diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh
new file mode 100755
index 0000000..33041f3
--- /dev/null
+++ b/t/t1001-read-tree-m-2way.sh
@@ -0,0 +1,281 @@
+#!/bin/sh
+#
+# Copyright (c) 2005 Junio C Hamano
+#
+
+test_description='Two way merge with read-tree -m $H $M
+
+This test tries two-way merge (aka fast forward with carry forward).
+
+There is the head (called H) and another commit (called M), which is
+simply ahead of H. The index and the work tree contains a state that
+is derived from H, but may also have local changes. This test checks
+all the combinations described in the two-tree merge "carry forward"
+rules, found in <Documentation/git-rev-tree.txt>.
+
+In the test, these paths are used:
+ bozbar - in H, stays in M, modified from bozbar to gnusto
+ frotz - not in H added in M
+ nitfol - in H, stays in M unmodified
+ rezrov - in H, deleted in M
+ yomin - not in H nor M
+'
+. ./test-lib.sh
+
+_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
+_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
+compare_change () {
+ sed >current \
+ -e '/^--- /d; /^+++ /d; /^@@ /d;' \
+ -e 's/^\(.[0-7][0-7][0-7][0-7][0-7][0-7]\) '"$_x40"' /\1 X /' "$1"
+ diff -u expected current
+}
+
+check_cache_at () {
+ clean_if_empty=`git-diff-files "$1"`
+ case "$clean_if_empty" in
+ '') echo "$1: clean" ;;
+ ?*) echo "$1: dirty" ;;
+ esac
+ case "$2,$clean_if_empty" in
+ clean,) : ;;
+ clean,?*) false ;;
+ dirty,) false ;;
+ dirty,?*) : ;;
+ esac
+}
+
+test_expect_success \
+ setup \
+ 'echo frotz >frotz &&
+ echo nitfol >nitfol &&
+ echo bozbar >bozbar &&
+ echo rezrov >rezrov &&
+ echo yomin >yomin &&
+ git-update-cache --add nitfol bozbar rezrov &&
+ treeH=`git-write-tree` &&
+ echo treeH $treeH &&
+ git-ls-tree $treeH &&
+
+ echo gnusto >bozbar &&
+ git-update-cache --add frotz bozbar --force-remove rezrov &&
+ git-ls-files --stage >M.out &&
+ treeM=`git-write-tree` &&
+ echo treeM $treeM &&
+ git-ls-tree $treeM &&
+ git-diff-tree $treeH $treeM'
+
+test_expect_success \
+ '1, 2, 3 - no carry forward' \
+ 'rm -f .git/index &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >1-3.out &&
+ cmp M.out 1-3.out &&
+ check_cache_at bozbar dirty &&
+ check_cache_at frotz dirty &&
+ check_cache_at nitfol dirty'
+
+echo '+100644 X 0 yomin' >expected
+
+test_expect_success \
+ '4 - carry forward local addition.' \
+ 'rm -f .git/index &&
+ git-update-cache --add yomin &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >4.out || exit
+ diff --unified=0 M.out 4.out >4diff.out
+ compare_change 4diff.out expected &&
+ check_cache_at yomin clean'
+
+test_expect_success \
+ '5 - carry forward local addition.' \
+ 'rm -f .git/index &&
+ echo yomin >yomin &&
+ git-update-cache --add yomin &&
+ echo yomin yomin >yomin &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >5.out || exit
+ diff --unified=0 M.out 5.out >5diff.out
+ compare_change 5diff.out expected &&
+ check_cache_at yomin dirty'
+
+test_expect_success \
+ '6 - local addition already has the same.' \
+ 'rm -f .git/index &&
+ git-update-cache --add frotz &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >6.out &&
+ diff --unified=0 M.out 6.out &&
+ check_cache_at frotz clean'
+
+test_expect_success \
+ '7 - local addition already has the same.' \
+ 'rm -f .git/index &&
+ echo frotz >frotz &&
+ git-update-cache --add frotz &&
+ echo frotz frotz >frotz &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >7.out &&
+ diff --unified=0 M.out 7.out &&
+ check_cache_at frotz dirty'
+
+test_expect_success \
+ '8 - conflicting addition.' \
+ 'rm -f .git/index &&
+ echo frotz frotz >frotz &&
+ git-update-cache --add frotz &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '9 - conflicting addition.' \
+ 'rm -f .git/index &&
+ echo frotz frotz >frotz &&
+ git-update-cache --add frotz &&
+ echo frotz >frotz &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '10 - path removed.' \
+ 'rm -f .git/index &&
+ echo rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >10.out &&
+ cmp M.out 10.out'
+
+test_expect_success \
+ '11 - dirty path removed.' \
+ 'rm -f .git/index &&
+ echo rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ echo rezrov rezrov >rezrov &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '12 - unmatching local changes being removed.' \
+ 'rm -f .git/index &&
+ echo rezrov rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '13 - unmatching local changes being removed.' \
+ 'rm -f .git/index &&
+ echo rezrov rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ echo rezrov >rezrov &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+cat >expected <<EOF
+-100644 X 0 nitfol
++100644 X 0 nitfol
+EOF
+
+test_expect_success \
+ '14 - unchanged in two heads.' \
+ 'rm -f .git/index &&
+ echo nitfol nitfol >nitfol &&
+ git-update-cache --add nitfol &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >14.out || exit
+ diff --unified=0 M.out 14.out >14diff.out
+ compare_change 14diff.out expected &&
+ check_cache_at nitfol clean'
+
+test_expect_success \
+ '15 - unchanged in two heads.' \
+ 'rm -f .git/index &&
+ echo nitfol nitfol >nitfol &&
+ git-update-cache --add nitfol &&
+ echo nitfol nitfol nitfol >nitfol &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >15.out || exit
+ diff --unified=0 M.out 15.out >15diff.out
+ compare_change 15diff.out expected &&
+ check_cache_at nitfol dirty'
+
+test_expect_success \
+ '16 - conflicting local change.' \
+ 'rm -f .git/index &&
+ echo bozbar bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '17 - conflicting local change.' \
+ 'rm -f .git/index &&
+ echo bozbar bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ echo bozbar bozbar bozbar >bozbar &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '18 - local change already having a good result.' \
+ 'rm -f .git/index &&
+ echo gnusto >bozbar &&
+ git-update-cache --add bozbar &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >18.out &&
+ diff --unified=0 M.out 18.out &&
+ check_cache_at bozbar clean'
+
+test_expect_success \
+ '19 - local change already having a good result, further modified.' \
+ 'rm -f .git/index &&
+ echo gnusto >bozbar &&
+ git-update-cache --add bozbar &&
+ echo gnusto gnusto >bozbar &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >19.out &&
+ diff --unified=0 M.out 19.out &&
+ check_cache_at bozbar dirty'
+
+test_expect_success \
+ '20 - no local change, use new tree.' \
+ 'rm -f .git/index &&
+ echo bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ git-read-tree -m $treeH $treeM &&
+ git-ls-files --stage >20.out &&
+ diff --unified=0 M.out 20.out &&
+ check_cache_at bozbar dirty'
+
+test_expect_success \
+ '21 - no local change, dirty cache.' \
+ 'rm -f .git/index &&
+ echo bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ echo gnusto gnusto >bozbar &&
+ if git-read-tree -m $treeH $treeM; then false; else :; fi'
+
+# Also make sure we did not break DF vs DF/DF case.
+test_expect_success \
+ 'DF vs DF/DF case setup.' \
+ 'rm -f .git/index &&
+ echo DF >DF &&
+ git-update-cache --add DF &&
+ treeDF=`git-write-tree` &&
+ echo treeDF $treeDF &&
+ git-ls-tree $treeDF &&
+
+ rm -f DF &&
+ mkdir DF &&
+ echo DF/DF >DF/DF &&
+ git-update-cache --add --remove DF DF/DF &&
+ treeDFDF=`git-write-tree` &&
+ echo treeDFDF $treeDFDF &&
+ git-ls-tree $treeDFDF &&
+ git-ls-files --stage >DFDF.out'
+
+test_expect_success \
+ 'DF vs DF/DF case test.' \
+ 'rm -f .git/index &&
+ rm -fr DF &&
+ echo DF >DF &&
+ git-update-cache --add DF &&
+ git-read-tree -m $treeDF $treeDFDF &&
+ git-ls-files --stage >DFDFcheck.out &&
+ diff --unified=0 DFDF.out DFDFcheck.out &&
+ check_cache_at DF/DF dirty'
+
+test_done
diff --git a/t/t1002-read-tree-m-u-2way.sh b/t/t1002-read-tree-m-u-2way.sh
new file mode 100755
index 0000000..75a4eaa
--- /dev/null
+++ b/t/t1002-read-tree-m-u-2way.sh
@@ -0,0 +1,307 @@
+#!/bin/sh
+#
+# Copyright (c) 2005 Junio C Hamano
+#
+
+test_description='Two way merge with read-tree -m -u $H $M
+
+This is identical to t1001, but uses -u to update the work tree as well.
+
+'
+. ./test-lib.sh
+
+_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
+_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
+compare_change () {
+ sed >current \
+ -e '/^--- /d; /^+++ /d; /^@@ /d;' \
+ -e 's/^\(.[0-7][0-7][0-7][0-7][0-7][0-7]\) '"$_x40"' /\1 X /' "$1"
+ diff -u expected current
+}
+
+check_cache_at () {
+ clean_if_empty=`git-diff-files "$1"`
+ case "$clean_if_empty" in
+ '') echo "$1: clean" ;;
+ ?*) echo "$1: dirty" ;;
+ esac
+ case "$2,$clean_if_empty" in
+ clean,) : ;;
+ clean,?*) false ;;
+ dirty,) false ;;
+ dirty,?*) : ;;
+ esac
+}
+
+test_expect_success \
+ setup \
+ 'echo frotz >frotz &&
+ echo nitfol >nitfol &&
+ echo bozbar >bozbar &&
+ echo rezrov >rezrov &&
+ echo yomin >yomin &&
+ git-update-cache --add nitfol bozbar rezrov &&
+ treeH=`git-write-tree` &&
+ echo treeH $treeH &&
+ git-ls-tree $treeH &&
+
+ echo gnusto >bozbar &&
+ git-update-cache --add frotz bozbar --force-remove rezrov &&
+ git-ls-files --stage >M.out &&
+ treeM=`git-write-tree` &&
+ echo treeM $treeM &&
+ git-ls-tree $treeM &&
+ sha1sum bozbar frotz nitfol >M.sha1 &&
+ git-diff-tree $treeH $treeM'
+
+test_expect_success \
+ '1, 2, 3 - no carry forward' \
+ 'rm -f .git/index &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >1-3.out &&
+ cmp M.out 1-3.out &&
+ sha1sum -c M.sha1 &&
+ check_cache_at bozbar clean &&
+ check_cache_at frotz clean &&
+ check_cache_at nitfol clean'
+
+echo '+100644 X 0 yomin' >expected
+
+test_expect_success \
+ '4 - carry forward local addition.' \
+ 'rm -f .git/index &&
+ git-update-cache --add yomin &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >4.out || exit
+ diff --unified=0 M.out 4.out >4diff.out
+ compare_change 4diff.out expected &&
+ check_cache_at yomin clean &&
+ sha1sum -c M.sha1 &&
+ echo yomin >yomin1 &&
+ diff yomin yomin1 &&
+ rm -f yomin1'
+
+test_expect_success \
+ '5 - carry forward local addition.' \
+ 'rm -f .git/index &&
+ echo yomin >yomin &&
+ git-update-cache --add yomin &&
+ echo yomin yomin >yomin &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >5.out || exit
+ diff --unified=0 M.out 5.out >5diff.out
+ compare_change 5diff.out expected &&
+ check_cache_at yomin dirty &&
+ sha1sum -c M.sha1 &&
+ : dirty index should have prevented -u from checking it out.
+ echo yomin yomin >yomin1 &&
+ diff yomin yomin1 &&
+ rm -f yomin1'
+
+test_expect_success \
+ '6 - local addition already has the same.' \
+ 'rm -f .git/index &&
+ git-update-cache --add frotz &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >6.out &&
+ diff --unified=0 M.out 6.out &&
+ check_cache_at frotz clean &&
+ sha1sum -c M.sha1 &&
+ echo frotz >frotz1 &&
+ diff frotz frotz1 &&
+ rm -f frotz1'
+
+test_expect_success \
+ '7 - local addition already has the same.' \
+ 'rm -f .git/index &&
+ echo frotz >frotz &&
+ git-update-cache --add frotz &&
+ echo frotz frotz >frotz &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >7.out &&
+ diff --unified=0 M.out 7.out &&
+ check_cache_at frotz dirty &&
+ if sha1sum -c M.sha1; then false; else :; fi &&
+ : dirty index should have prevented -u from checking it out.
+ echo frotz frotz >frotz1 &&
+ diff frotz frotz1 &&
+ rm -f frotz1'
+
+test_expect_success \
+ '8 - conflicting addition.' \
+ 'rm -f .git/index &&
+ echo frotz frotz >frotz &&
+ git-update-cache --add frotz &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '9 - conflicting addition.' \
+ 'rm -f .git/index &&
+ echo frotz frotz >frotz &&
+ git-update-cache --add frotz &&
+ echo frotz >frotz &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '10 - path removed.' \
+ 'rm -f .git/index &&
+ echo rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >10.out &&
+ cmp M.out 10.out &&
+ sha1sum -c M.sha1'
+
+test_expect_success \
+ '11 - dirty path removed.' \
+ 'rm -f .git/index &&
+ echo rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ echo rezrov rezrov >rezrov &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '12 - unmatching local changes being removed.' \
+ 'rm -f .git/index &&
+ echo rezrov rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '13 - unmatching local changes being removed.' \
+ 'rm -f .git/index &&
+ echo rezrov rezrov >rezrov &&
+ git-update-cache --add rezrov &&
+ echo rezrov >rezrov &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+cat >expected <<EOF
+-100644 X 0 nitfol
++100644 X 0 nitfol
+EOF
+
+test_expect_success \
+ '14 - unchanged in two heads.' \
+ 'rm -f .git/index &&
+ echo nitfol nitfol >nitfol &&
+ git-update-cache --add nitfol &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >14.out || exit
+ diff --unified=0 M.out 14.out >14diff.out
+ compare_change 14diff.out expected &&
+ check_cache_at nitfol clean &&
+ grep -v nitfol M.sha1 | sha1sum -c &&
+ if sha1sum -c M.sha1; then false; else :; fi &&
+ echo nitfol nitfol >nitfol1 &&
+ diff nitfol nitfol1 &&
+ rm -f nitfol1'
+
+test_expect_success \
+ '15 - unchanged in two heads.' \
+ 'rm -f .git/index &&
+ echo nitfol nitfol >nitfol &&
+ git-update-cache --add nitfol &&
+ echo nitfol nitfol nitfol >nitfol &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >15.out || exit
+ diff --unified=0 M.out 15.out >15diff.out
+ compare_change 15diff.out expected &&
+ check_cache_at nitfol dirty &&
+ grep -v nitfol M.sha1 | sha1sum -c &&
+ if sha1sum -c M.sha1; then false; else :; fi &&
+ echo nitfol nitfol nitfol >nitfol1 &&
+ diff nitfol nitfol1 &&
+ rm -f nitfol1'
+
+test_expect_success \
+ '16 - conflicting local change.' \
+ 'rm -f .git/index &&
+ echo bozbar bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '17 - conflicting local change.' \
+ 'rm -f .git/index &&
+ echo bozbar bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ echo bozbar bozbar bozbar >bozbar &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+test_expect_success \
+ '18 - local change already having a good result.' \
+ 'rm -f .git/index &&
+ echo gnusto >bozbar &&
+ git-update-cache --add bozbar &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >18.out &&
+ diff --unified=0 M.out 18.out &&
+ check_cache_at bozbar clean &&
+ sha1sum -c M.sha1'
+
+test_expect_success \
+ '19 - local change already having a good result, further modified.' \
+ 'rm -f .git/index &&
+ echo gnusto >bozbar &&
+ git-update-cache --add bozbar &&
+ echo gnusto gnusto >bozbar &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >19.out &&
+ diff --unified=0 M.out 19.out &&
+ check_cache_at bozbar dirty &&
+ grep -v bozbar M.sha1 | sha1sum -c &&
+ if sha1sum -c M.sha1; then false; else :; fi &&
+ echo gnusto gnusto >bozbar1 &&
+ diff bozbar bozbar1 &&
+ rm -f bozbar1'
+
+test_expect_success \
+ '20 - no local change, use new tree.' \
+ 'rm -f .git/index &&
+ echo bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ git-read-tree -m -u $treeH $treeM &&
+ git-ls-files --stage >20.out &&
+ diff --unified=0 M.out 20.out &&
+ check_cache_at bozbar clean &&
+ sha1sum -c M.sha1'
+
+test_expect_success \
+ '21 - no local change, dirty cache.' \
+ 'rm -f .git/index &&
+ echo bozbar >bozbar &&
+ git-update-cache --add bozbar &&
+ echo gnusto gnusto >bozbar &&
+ if git-read-tree -m -u $treeH $treeM; then false; else :; fi'
+
+# Also make sure we did not break DF vs DF/DF case.
+test_expect_success \
+ 'DF vs DF/DF case setup.' \
+ 'rm -f .git/index &&
+ echo DF >DF &&
+ git-update-cache --add DF &&
+ treeDF=`git-write-tree` &&
+ echo treeDF $treeDF &&
+ git-ls-tree $treeDF &&
+
+ rm -f DF &&
+ mkdir DF &&
+ echo DF/DF >DF/DF &&
+ git-update-cache --add --remove DF DF/DF &&
+ treeDFDF=`git-write-tree` &&
+ echo treeDFDF $treeDFDF &&
+ git-ls-tree $treeDFDF &&
+ git-ls-files --stage >DFDF.out'
+
+test_expect_success \
+ 'DF vs DF/DF case test.' \
+ 'rm -f .git/index &&
+ rm -fr DF &&
+ echo DF >DF &&
+ git-update-cache --add DF &&
+ git-read-tree -m -u $treeDF $treeDFDF &&
+ git-ls-files --stage >DFDFcheck.out &&
+ diff --unified=0 DFDF.out DFDFcheck.out &&
+ check_cache_at DF/DF clean'
+
+test_done