Merge branch 'sb/unpack-trees-super-prefix'

"git read-tree" and its underlying unpack_trees() machinery learned
to report problematic paths prefixed with the --super-prefix option.

* sb/unpack-trees-super-prefix:
  unpack-trees: support super-prefix option
  t1001: modernize style
  t1000: modernize style
  read-tree: use OPT_BOOL instead of OPT_SET_INT

2 files changed, 643 insertions, 654 deletions

diff --git a/t/t1000-read-tree-m-3way.sh b/t/t1000-read-tree-m-3way.sh
index a0b79b483..3c4d2d604 100755
--- a/t/t1000-read-tree-m-3way.sh
+++ b/t/t1000-read-tree-m-3way.sh
@@ -128,29 +128,29 @@ cat >expected <<\EOF
 EOF
 
 check_result () {
-    git ls-files --stage | sed -e 's/ '"$_x40"' / X /' >current &&
-    test_cmp expected current
+	git ls-files --stage | sed -e 's/ '"$_x40"' / X /' >current &&
+	test_cmp expected current
 }
 
 # This is done on an empty work directory, which is the normal
 # merge person behaviour.
-test_expect_success \
-    '3-way merge with git read-tree -m, empty cache' \
-    "rm -fr [NDMALTS][NDMALTSF] Z &&
-     rm .git/index &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
+test_expect_success '3-way merge with git read-tree -m, empty cache' '
+	rm -fr [NDMALTS][NDMALTSF] Z &&
+	rm .git/index &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
 
 # This starts out with the first head, which is the normal
 # patch submitter behaviour.
-test_expect_success \
-    '3-way merge with git read-tree -m, match H' \
-    "rm -fr [NDMALTS][NDMALTSF] Z &&
-     rm .git/index &&
-     read_tree_must_succeed $tree_A &&
-     git checkout-index -f -u -a &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
+test_expect_success '3-way merge with git read-tree -m, match H' '
+	rm -fr [NDMALTS][NDMALTSF] Z &&
+	rm .git/index &&
+	read_tree_must_succeed $tree_A &&
+	git checkout-index -f -u -a &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
 
 : <<\END_OF_CASE_TABLE
 
@@ -208,322 +208,304 @@ DF (file) when tree B require DF to be a directory by having DF/DF
 
 END_OF_CASE_TABLE
 
-test_expect_success '1 - must not have an entry not in A.' "
-     rm -f .git/index XX &&
-     echo XX >XX &&
-     git update-index --add XX &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '2 - must match B in !O && !A && B case.' \
-    "rm -f .git/index NA &&
-     cp .orig-B/NA NA &&
-     git update-index --add NA &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B"
-
-test_expect_success \
-    '2 - matching B alone is OK in !O && !A && B case.' \
-    "rm -f .git/index NA &&
-     cp .orig-B/NA NA &&
-     git update-index --add NA &&
-     echo extra >>NA &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B"
-
-test_expect_success \
-    '3 - must match A in !O && A && !B case.' \
-    "rm -f .git/index AN &&
-     cp .orig-A/AN AN &&
-     git update-index --add AN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '3 - matching A alone is OK in !O && A && !B case.' \
-    "rm -f .git/index AN &&
-     cp .orig-A/AN AN &&
-     git update-index --add AN &&
-     echo extra >>AN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B"
-
-test_expect_success \
-    '3 (fail) - must match A in !O && A && !B case.' "
-     rm -f .git/index AN &&
-     cp .orig-A/AN AN &&
-     echo extra >>AN &&
-     git update-index --add AN &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '4 - must match and be up-to-date in !O && A && B && A!=B case.' \
-    "rm -f .git/index AA &&
-     cp .orig-A/AA AA &&
-     git update-index --add AA &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '4 (fail) - must match and be up-to-date in !O && A && B && A!=B case.' "
-     rm -f .git/index AA &&
-     cp .orig-A/AA AA &&
-     git update-index --add AA &&
-     echo extra >>AA &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '4 (fail) - must match and be up-to-date in !O && A && B && A!=B case.' "
-     rm -f .git/index AA &&
-     cp .orig-A/AA AA &&
-     echo extra >>AA &&
-     git update-index --add AA &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '5 - must match in !O && A && B && A==B case.' \
-    "rm -f .git/index LL &&
-     cp .orig-A/LL LL &&
-     git update-index --add LL &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '5 - must match in !O && A && B && A==B case.' \
-    "rm -f .git/index LL &&
-     cp .orig-A/LL LL &&
-     git update-index --add LL &&
-     echo extra >>LL &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '5 (fail) - must match A in !O && A && B && A==B case.' "
-     rm -f .git/index LL &&
-     cp .orig-A/LL LL &&
-     echo extra >>LL &&
-     git update-index --add LL &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '6 - must not exist in O && !A && !B case' "
-     rm -f .git/index DD &&
-     echo DD >DD &&
-     git update-index --add DD &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '7 - must not exist in O && !A && B && O!=B case' "
-     rm -f .git/index DM &&
-     cp .orig-B/DM DM &&
-     git update-index --add DM &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '8 - must not exist in O && !A && B && O==B case' "
-     rm -f .git/index DN &&
-     cp .orig-B/DN DN &&
-     git update-index --add DN &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '9 - must match and be up-to-date in O && A && !B && O!=A case' \
-    "rm -f .git/index MD &&
-     cp .orig-A/MD MD &&
-     git update-index --add MD &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '9 (fail) - must match and be up-to-date in O && A && !B && O!=A case' "
-     rm -f .git/index MD &&
-     cp .orig-A/MD MD &&
-     git update-index --add MD &&
-     echo extra >>MD &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '9 (fail) - must match and be up-to-date in O && A && !B && O!=A case' "
-     rm -f .git/index MD &&
-     cp .orig-A/MD MD &&
-     echo extra >>MD &&
-     git update-index --add MD &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '10 - must match and be up-to-date in O && A && !B && O==A case' \
-    "rm -f .git/index ND &&
-     cp .orig-A/ND ND &&
-     git update-index --add ND &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '10 (fail) - must match and be up-to-date in O && A && !B && O==A case' "
-     rm -f .git/index ND &&
-     cp .orig-A/ND ND &&
-     git update-index --add ND &&
-     echo extra >>ND &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '10 (fail) - must match and be up-to-date in O && A && !B && O==A case' "
-     rm -f .git/index ND &&
-     cp .orig-A/ND ND &&
-     echo extra >>ND &&
-     git update-index --add ND &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '11 - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' \
-    "rm -f .git/index MM &&
-     cp .orig-A/MM MM &&
-     git update-index --add MM &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '11 (fail) - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' "
-     rm -f .git/index MM &&
-     cp .orig-A/MM MM &&
-     git update-index --add MM &&
-     echo extra >>MM &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '11 (fail) - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' "
-     rm -f .git/index MM &&
-     cp .orig-A/MM MM &&
-     echo extra >>MM &&
-     git update-index --add MM &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '12 - must match A in O && A && B && O!=A && A==B case' \
-    "rm -f .git/index SS &&
-     cp .orig-A/SS SS &&
-     git update-index --add SS &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '12 - must match A in O && A && B && O!=A && A==B case' \
-    "rm -f .git/index SS &&
-     cp .orig-A/SS SS &&
-     git update-index --add SS &&
-     echo extra >>SS &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '12 (fail) - must match A in O && A && B && O!=A && A==B case' "
-     rm -f .git/index SS &&
-     cp .orig-A/SS SS &&
-     echo extra >>SS &&
-     git update-index --add SS &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '13 - must match A in O && A && B && O!=A && O==B case' \
-    "rm -f .git/index MN &&
-     cp .orig-A/MN MN &&
-     git update-index --add MN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '13 - must match A in O && A && B && O!=A && O==B case' \
-    "rm -f .git/index MN &&
-     cp .orig-A/MN MN &&
-     git update-index --add MN &&
-     echo extra >>MN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '14 - must match and be up-to-date in O && A && B && O==A && O!=B case' \
-    "rm -f .git/index NM &&
-     cp .orig-A/NM NM &&
-     git update-index --add NM &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '14 - may match B in O && A && B && O==A && O!=B case' \
-    "rm -f .git/index NM &&
-     cp .orig-B/NM NM &&
-     git update-index --add NM &&
-     echo extra >>NM &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '14 (fail) - must match and be up-to-date in O && A && B && O==A && O!=B case' "
-     rm -f .git/index NM &&
-     cp .orig-A/NM NM &&
-     git update-index --add NM &&
-     echo extra >>NM &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '14 (fail) - must match and be up-to-date in O && A && B && O==A && O!=B case' "
-     rm -f .git/index NM &&
-     cp .orig-A/NM NM &&
-     echo extra >>NM &&
-     git update-index --add NM &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-test_expect_success \
-    '15 - must match A in O && A && B && O==A && O==B case' \
-    "rm -f .git/index NN &&
-     cp .orig-A/NN NN &&
-     git update-index --add NN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '15 - must match A in O && A && B && O==A && O==B case' \
-    "rm -f .git/index NN &&
-     cp .orig-A/NN NN &&
-     git update-index --add NN &&
-     echo extra >>NN &&
-     read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
-     check_result"
-
-test_expect_success \
-    '15 (fail) - must match A in O && A && B && O==A && O==B case' "
-     rm -f .git/index NN &&
-     cp .orig-A/NN NN &&
-     echo extra >>NN &&
-     git update-index --add NN &&
-     read_tree_must_fail -m $tree_O $tree_A $tree_B
-"
-
-# #16
-test_expect_success \
-    '16 - A matches in one and B matches in another.' \
-    'rm -f .git/index F16 &&
-    echo F16 >F16 &&
-    git update-index --add F16 &&
-    tree0=$(git write-tree) &&
-    echo E16 >F16 &&
-    git update-index F16 &&
-    tree1=$(git write-tree) &&
-    read_tree_must_succeed -m $tree0 $tree1 $tree1 $tree0 &&
-    git ls-files --stage'
+test_expect_success '1 - must not have an entry not in A.' '
+	rm -f .git/index XX &&
+	echo XX >XX &&
+	git update-index --add XX &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '2 - must match B in !O && !A && B case.' '
+	rm -f .git/index NA &&
+	cp .orig-B/NA NA &&
+	git update-index --add NA &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '2 - matching B alone is OK in !O && !A && B case.' '
+	rm -f .git/index NA &&
+	cp .orig-B/NA NA &&
+	git update-index --add NA &&
+	echo extra >>NA &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '3 - must match A in !O && A && !B case.' '
+	rm -f .git/index AN &&
+	cp .orig-A/AN AN &&
+	git update-index --add AN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '3 - matching A alone is OK in !O && A && !B case.' '
+	rm -f .git/index AN &&
+	cp .orig-A/AN AN &&
+	git update-index --add AN &&
+	echo extra >>AN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '3 (fail) - must match A in !O && A && !B case.' '
+	rm -f .git/index AN &&
+	cp .orig-A/AN AN &&
+	echo extra >>AN &&
+	git update-index --add AN &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '4 - must match and be up-to-date in !O && A && B && A!=B case.' '
+	rm -f .git/index AA &&
+	cp .orig-A/AA AA &&
+	git update-index --add AA &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '4 (fail) - must match and be up-to-date in !O && A && B && A!=B case.' '
+	rm -f .git/index AA &&
+	cp .orig-A/AA AA &&
+	git update-index --add AA &&
+	echo extra >>AA &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '4 (fail) - must match and be up-to-date in !O && A && B && A!=B case.' '
+	rm -f .git/index AA &&
+	cp .orig-A/AA AA &&
+	echo extra >>AA &&
+	git update-index --add AA &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '5 - must match in !O && A && B && A==B case.' '
+	rm -f .git/index LL &&
+	cp .orig-A/LL LL &&
+	git update-index --add LL &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '5 - must match in !O && A && B && A==B case.' '
+	rm -f .git/index LL &&
+	cp .orig-A/LL LL &&
+	git update-index --add LL &&
+	echo extra >>LL &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '5 (fail) - must match A in !O && A && B && A==B case.' '
+	rm -f .git/index LL &&
+	cp .orig-A/LL LL &&
+	echo extra >>LL &&
+	git update-index --add LL &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '6 - must not exist in O && !A && !B case' '
+	rm -f .git/index DD &&
+	echo DD >DD &&
+	git update-index --add DD &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '7 - must not exist in O && !A && B && O!=B case' '
+	rm -f .git/index DM &&
+	cp .orig-B/DM DM &&
+	git update-index --add DM &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '8 - must not exist in O && !A && B && O==B case' '
+	rm -f .git/index DN &&
+	cp .orig-B/DN DN &&
+	git update-index --add DN &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '9 - must match and be up-to-date in O && A && !B && O!=A case' '
+	rm -f .git/index MD &&
+	cp .orig-A/MD MD &&
+	git update-index --add MD &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '9 (fail) - must match and be up-to-date in O && A && !B && O!=A case' '
+	rm -f .git/index MD &&
+	cp .orig-A/MD MD &&
+	git update-index --add MD &&
+	echo extra >>MD &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '9 (fail) - must match and be up-to-date in O && A && !B && O!=A case' '
+	rm -f .git/index MD &&
+	cp .orig-A/MD MD &&
+	echo extra >>MD &&
+	git update-index --add MD &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '10 - must match and be up-to-date in O && A && !B && O==A case' '
+	rm -f .git/index ND &&
+	cp .orig-A/ND ND &&
+	git update-index --add ND &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '10 (fail) - must match and be up-to-date in O && A && !B && O==A case' '
+	rm -f .git/index ND &&
+	cp .orig-A/ND ND &&
+	git update-index --add ND &&
+	echo extra >>ND &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '10 (fail) - must match and be up-to-date in O && A && !B && O==A case' '
+	rm -f .git/index ND &&
+	cp .orig-A/ND ND &&
+	echo extra >>ND &&
+	git update-index --add ND &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '11 - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' '
+	rm -f .git/index MM &&
+	cp .orig-A/MM MM &&
+	git update-index --add MM &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '11 (fail) - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' '
+	rm -f .git/index MM &&
+	cp .orig-A/MM MM &&
+	git update-index --add MM &&
+	echo extra >>MM &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '11 (fail) - must match and be up-to-date in O && A && B && O!=A && O!=B && A!=B case' '
+	rm -f .git/index MM &&
+	cp .orig-A/MM MM &&
+	echo extra >>MM &&
+	git update-index --add MM &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '12 - must match A in O && A && B && O!=A && A==B case' '
+	rm -f .git/index SS &&
+	cp .orig-A/SS SS &&
+	git update-index --add SS &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '12 - must match A in O && A && B && O!=A && A==B case' '
+	rm -f .git/index SS &&
+	cp .orig-A/SS SS &&
+	git update-index --add SS &&
+	echo extra >>SS &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '12 (fail) - must match A in O && A && B && O!=A && A==B case' '
+	rm -f .git/index SS &&
+	cp .orig-A/SS SS &&
+	echo extra >>SS &&
+	git update-index --add SS &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '13 - must match A in O && A && B && O!=A && O==B case' '
+	rm -f .git/index MN &&
+	cp .orig-A/MN MN &&
+	git update-index --add MN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '13 - must match A in O && A && B && O!=A && O==B case' '
+	rm -f .git/index MN &&
+	cp .orig-A/MN MN &&
+	git update-index --add MN &&
+	echo extra >>MN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '14 - must match and be up-to-date in O && A && B && O==A && O!=B case' '
+	rm -f .git/index NM &&
+	cp .orig-A/NM NM &&
+	git update-index --add NM &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '14 - may match B in O && A && B && O==A && O!=B case' '
+	rm -f .git/index NM &&
+	cp .orig-B/NM NM &&
+	git update-index --add NM &&
+	echo extra >>NM &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '14 (fail) - must match and be up-to-date in O && A && B && O==A && O!=B case' '
+	rm -f .git/index NM &&
+	cp .orig-A/NM NM &&
+	git update-index --add NM &&
+	echo extra >>NM &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '14 (fail) - must match and be up-to-date in O && A && B && O==A && O!=B case' '
+	rm -f .git/index NM &&
+	cp .orig-A/NM NM &&
+	echo extra >>NM &&
+	git update-index --add NM &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '15 - must match A in O && A && B && O==A && O==B case' '
+	rm -f .git/index NN &&
+	cp .orig-A/NN NN &&
+	git update-index --add NN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '15 - must match A in O && A && B && O==A && O==B case' '
+	rm -f .git/index NN &&
+	cp .orig-A/NN NN &&
+	git update-index --add NN &&
+	echo extra >>NN &&
+	read_tree_must_succeed -m $tree_O $tree_A $tree_B &&
+	check_result
+'
+
+test_expect_success '15 (fail) - must match A in O && A && B && O==A && O==B case' '
+	rm -f .git/index NN &&
+	cp .orig-A/NN NN &&
+	echo extra >>NN &&
+	git update-index --add NN &&
+	read_tree_must_fail -m $tree_O $tree_A $tree_B
+'
+
+test_expect_success '16 - A matches in one and B matches in another.' '
+	rm -f .git/index F16 &&
+	echo F16 >F16 &&
+	git update-index --add F16 &&
+	tree0=$(git write-tree) &&
+	echo E16 >F16 &&
+	git update-index F16 &&
+	tree1=$(git write-tree) &&
+	read_tree_must_succeed -m $tree0 $tree1 $tree1 $tree0 &&
+	git ls-files --stage
+'
 
 test_done
diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh
index db1b6f5cf..5ededd8e4 100755
--- a/t/t1001-read-tree-m-2way.sh
+++ b/t/t1001-read-tree-m-2way.sh
@@ -14,10 +14,10 @@ all the combinations described in the two-tree merge "carry forward"
 rules, found in <Documentation/git read-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
+	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 or M
 '
 . ./test-lib.sh
@@ -60,336 +60,343 @@ EOF
 
 sed -e 's/bozbar/gnusto (earlier bozbar)/' bozbar-old >bozbar-new
 
-test_expect_success \
-    setup \
-    'echo frotz >frotz &&
-     echo nitfol >nitfol &&
-     cat bozbar-old >bozbar &&
-     echo rezrov >rezrov &&
-     echo yomin >yomin &&
-     git update-index --add nitfol bozbar rezrov &&
-     treeH=$(git write-tree) &&
-     echo treeH $treeH &&
-     git ls-tree $treeH &&
-
-     cat bozbar-new >bozbar &&
-     git update-index --add frotz bozbar --force-remove rezrov &&
-     git ls-files --stage >M.out &&
-     treeM=$(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 &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >1-3.out &&
-     test_cmp M.out 1-3.out &&
-     check_cache_at bozbar dirty &&
-     check_cache_at frotz dirty &&
-     check_cache_at nitfol dirty'
+test_expect_success 'setup' '
+	echo frotz >frotz &&
+	echo nitfol >nitfol &&
+	cat bozbar-old >bozbar &&
+	echo rezrov >rezrov &&
+	echo yomin >yomin &&
+	git update-index --add nitfol bozbar rezrov &&
+	treeH=$(git write-tree) &&
+	echo treeH $treeH &&
+	git ls-tree $treeH &&
+
+	cat bozbar-new >bozbar &&
+	git update-index --add frotz bozbar --force-remove rezrov &&
+	git ls-files --stage >M.out &&
+	treeM=$(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 &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >1-3.out &&
+	test_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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     git update-index --add yomin &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >4.out &&
-     test_must_fail git diff --no-index 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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo yomin >yomin &&
-     git update-index --add yomin &&
-     echo yomin yomin >yomin &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >5.out &&
-     test_must_fail git diff --no-index 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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     git update-index --add frotz &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >6.out &&
-     test_cmp M.out 6.out &&
-     check_cache_at frotz clean'
-
-test_expect_success \
-    '7 - local addition already has the same.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo frotz >frotz &&
-     git update-index --add frotz &&
-     echo frotz frotz >frotz &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >7.out &&
-     test_cmp M.out 7.out &&
-     check_cache_at frotz dirty'
-
-test_expect_success \
-    '8 - conflicting addition.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo frotz frotz >frotz &&
-     git update-index --add frotz &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '9 - conflicting addition.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo frotz frotz >frotz &&
-     git update-index --add frotz &&
-     echo frotz >frotz &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '10 - path removed.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo rezrov >rezrov &&
-     git update-index --add rezrov &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >10.out &&
-     test_cmp M.out 10.out'
-
-test_expect_success \
-    '11 - dirty path removed.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo rezrov >rezrov &&
-     git update-index --add rezrov &&
-     echo rezrov rezrov >rezrov &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '12 - unmatching local changes being removed.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo rezrov rezrov >rezrov &&
-     git update-index --add rezrov &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '13 - unmatching local changes being removed.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo rezrov rezrov >rezrov &&
-     git update-index --add rezrov &&
-     echo rezrov >rezrov &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
+test_expect_success '4 - carry forward local addition.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	git update-index --add yomin &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >4.out &&
+	test_must_fail git diff --no-index 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 &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo yomin >yomin &&
+	git update-index --add yomin &&
+	echo yomin yomin >yomin &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >5.out &&
+	test_must_fail git diff --no-index 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 &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	git update-index --add frotz &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >6.out &&
+	test_cmp M.out 6.out &&
+	check_cache_at frotz clean
+'
+
+test_expect_success '7 - local addition already has the same.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo frotz >frotz &&
+	git update-index --add frotz &&
+	echo frotz frotz >frotz &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >7.out &&
+	test_cmp M.out 7.out &&
+	check_cache_at frotz dirty
+'
+
+test_expect_success '8 - conflicting addition.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo frotz frotz >frotz &&
+	git update-index --add frotz &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '9 - conflicting addition.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo frotz frotz >frotz &&
+	git update-index --add frotz &&
+	echo frotz >frotz &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '10 - path removed.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo rezrov >rezrov &&
+	git update-index --add rezrov &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >10.out &&
+	test_cmp M.out 10.out
+'
+
+test_expect_success '11 - dirty path removed.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo rezrov >rezrov &&
+	git update-index --add rezrov &&
+	echo rezrov rezrov >rezrov &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '12 - unmatching local changes being removed.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo rezrov rezrov >rezrov &&
+	git update-index --add rezrov &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '13 - unmatching local changes being removed.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo rezrov rezrov >rezrov &&
+	git update-index --add rezrov &&
+	echo rezrov >rezrov &&
+	if read_tree_twoway $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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo nitfol nitfol >nitfol &&
-     git update-index --add nitfol &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >14.out &&
-     test_must_fail git diff --no-index 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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo nitfol nitfol >nitfol &&
-     git update-index --add nitfol &&
-     echo nitfol nitfol nitfol >nitfol &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >15.out &&
-     test_must_fail git diff --no-index 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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo bozbar bozbar >bozbar &&
-     git update-index --add bozbar &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '17 - conflicting local change.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     echo bozbar bozbar >bozbar &&
-     git update-index --add bozbar &&
-     echo bozbar bozbar bozbar >bozbar &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
-
-test_expect_success \
-    '18 - local change already having a good result.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     cat bozbar-new >bozbar &&
-     git update-index --add bozbar &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >18.out &&
-     test_cmp 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 &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     cat bozbar-new >bozbar &&
-     git update-index --add bozbar &&
-     echo gnusto gnusto >bozbar &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >19.out &&
-     test_cmp M.out 19.out &&
-     check_cache_at bozbar dirty'
-
-test_expect_success \
-    '20 - no local change, use new tree.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     cat bozbar-old >bozbar &&
-     git update-index --add bozbar &&
-     read_tree_twoway $treeH $treeM &&
-     git ls-files --stage >20.out &&
-     test_cmp M.out 20.out &&
-     check_cache_at bozbar dirty'
-
-test_expect_success \
-    '21 - no local change, dirty cache.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     cat bozbar-old >bozbar &&
-     git update-index --add bozbar &&
-     echo gnusto gnusto >bozbar &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
+test_expect_success '14 - unchanged in two heads.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo nitfol nitfol >nitfol &&
+	git update-index --add nitfol &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >14.out &&
+	test_must_fail git diff --no-index 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 &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo nitfol nitfol >nitfol &&
+	git update-index --add nitfol &&
+	echo nitfol nitfol nitfol >nitfol &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >15.out &&
+	test_must_fail git diff --no-index 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 &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo bozbar bozbar >bozbar &&
+	git update-index --add bozbar &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '17 - conflicting local change.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	echo bozbar bozbar >bozbar &&
+	git update-index --add bozbar &&
+	echo bozbar bozbar bozbar >bozbar &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
+
+test_expect_success '18 - local change already having a good result.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	cat bozbar-new >bozbar &&
+	git update-index --add bozbar &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >18.out &&
+	test_cmp 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 &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	cat bozbar-new >bozbar &&
+	git update-index --add bozbar &&
+	echo gnusto gnusto >bozbar &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >19.out &&
+	test_cmp M.out 19.out &&
+	check_cache_at bozbar dirty
+'
+
+test_expect_success '20 - no local change, use new tree.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	cat bozbar-old >bozbar &&
+	git update-index --add bozbar &&
+	read_tree_twoway $treeH $treeM &&
+	git ls-files --stage >20.out &&
+	test_cmp M.out 20.out &&
+	check_cache_at bozbar dirty
+'
+
+test_expect_success '21 - no local change, dirty cache.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	cat bozbar-old >bozbar &&
+	git update-index --add bozbar &&
+	echo gnusto gnusto >bozbar &&
+	if read_tree_twoway $treeH $treeM; then false; else :; fi
+'
 
 # This fails with straight two-way fast-forward.
-test_expect_success \
-    '22 - local change cache updated.' \
-    'rm -f .git/index &&
-     read_tree_must_succeed $treeH &&
-     git checkout-index -u -f -q -a &&
-     sed -e "s/such as/SUCH AS/" bozbar-old >bozbar &&
-     git update-index --add bozbar &&
-     if read_tree_twoway $treeH $treeM; then false; else :; fi'
+test_expect_success '22 - local change cache updated.' '
+	rm -f .git/index &&
+	read_tree_must_succeed $treeH &&
+	git checkout-index -u -f -q -a &&
+	sed -e "s/such as/SUCH AS/" bozbar-old >bozbar &&
+	git update-index --add bozbar &&
+	if read_tree_twoway $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-index --add DF &&
-     treeDF=$(git write-tree) &&
-     echo treeDF $treeDF &&
-     git ls-tree $treeDF &&
-
-     rm -f DF &&
-     mkdir DF &&
-     echo DF/DF >DF/DF &&
-     git update-index --add --remove DF DF/DF &&
-     treeDFDF=$(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-index --add DF &&
-     read_tree_twoway $treeDF $treeDFDF &&
-     git ls-files --stage >DFDFcheck.out &&
-     test_cmp DFDF.out DFDFcheck.out &&
-     check_cache_at DF/DF dirty &&
-     :'
-
-test_expect_success \
-    'a/b (untracked) vs a case setup.' \
-    'rm -f .git/index &&
-     : >a &&
-     git update-index --add a &&
-     treeM=$(git write-tree) &&
-     echo treeM $treeM &&
-     git ls-tree $treeM &&
-     git ls-files --stage >treeM.out &&
-
-     rm -f a &&
-     git update-index --remove a &&
-     mkdir a &&
-     : >a/b &&
-     treeH=$(git write-tree) &&
-     echo treeH $treeH &&
-     git ls-tree $treeH'
-
-test_expect_success \
-    'a/b (untracked) vs a, plus c/d case test.' \
-    'read_tree_u_must_fail -u -m "$treeH" "$treeM" &&
-     git ls-files --stage &&
-     test -f a/b'
-
-test_expect_success \
-    'a/b vs a, plus c/d case setup.' \
-    'rm -f .git/index &&
-     rm -fr a &&
-     : >a &&
-     mkdir c &&
-     : >c/d &&
-     git update-index --add a c/d &&
-     treeM=$(git write-tree) &&
-     echo treeM $treeM &&
-     git ls-tree $treeM &&
-     git ls-files --stage >treeM.out &&
-
-     rm -f a &&
-     mkdir a &&
-     : >a/b &&
-     git update-index --add --remove a a/b &&
-     treeH=$(git write-tree) &&
-     echo treeH $treeH &&
-     git ls-tree $treeH'
-
-test_expect_success \
-    'a/b vs a, plus c/d case test.' \
-    'read_tree_u_must_succeed -u -m "$treeH" "$treeM" &&
-     git ls-files --stage | tee >treeMcheck.out &&
-     test_cmp treeM.out treeMcheck.out'
+test_expect_success 'DF vs DF/DF case setup.' '
+	rm -f .git/index &&
+	echo DF >DF &&
+	git update-index --add DF &&
+	treeDF=$(git write-tree) &&
+	echo treeDF $treeDF &&
+	git ls-tree $treeDF &&
+
+	rm -f DF &&
+	mkdir DF &&
+	echo DF/DF >DF/DF &&
+	git update-index --add --remove DF DF/DF &&
+	treeDFDF=$(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-index --add DF &&
+	read_tree_twoway $treeDF $treeDFDF &&
+	git ls-files --stage >DFDFcheck.out &&
+	test_cmp DFDF.out DFDFcheck.out &&
+	check_cache_at DF/DF dirty &&
+	:
+'
+
+test_expect_success 'a/b (untracked) vs a case setup.' '
+	rm -f .git/index &&
+	: >a &&
+	git update-index --add a &&
+	treeM=$(git write-tree) &&
+	echo treeM $treeM &&
+	git ls-tree $treeM &&
+	git ls-files --stage >treeM.out &&
+
+	rm -f a &&
+	git update-index --remove a &&
+	mkdir a &&
+	: >a/b &&
+	treeH=$(git write-tree) &&
+	echo treeH $treeH &&
+	git ls-tree $treeH
+'
+
+test_expect_success 'a/b (untracked) vs a, plus c/d case test.' '
+	read_tree_u_must_fail -u -m "$treeH" "$treeM" &&
+	git ls-files --stage &&
+	test -f a/b
+'
+
+test_expect_success 'read-tree supports the super-prefix' '
+	cat <<-EOF >expect &&
+		error: Updating '\''fictional/a'\'' would lose untracked files in it
+	EOF
+	test_must_fail git --super-prefix fictional/ read-tree -u -m "$treeH" "$treeM" 2>actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'a/b vs a, plus c/d case setup.' '
+	rm -f .git/index &&
+	rm -fr a &&
+	: >a &&
+	mkdir c &&
+	: >c/d &&
+	git update-index --add a c/d &&
+	treeM=$(git write-tree) &&
+	echo treeM $treeM &&
+	git ls-tree $treeM &&
+	git ls-files --stage >treeM.out &&
+
+	rm -f a &&
+	mkdir a &&
+	: >a/b &&
+	git update-index --add --remove a a/b &&
+	treeH=$(git write-tree) &&
+	echo treeH $treeH &&
+	git ls-tree $treeH
+'
+
+test_expect_success 'a/b vs a, plus c/d case test.' '
+	read_tree_u_must_succeed -u -m "$treeH" "$treeM" &&
+	git ls-files --stage | tee >treeMcheck.out &&
+	test_cmp treeM.out treeMcheck.out
+'
 
 test_expect_success '-m references the correct modified tree' '
 	echo >file-a &&