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diff --git a/t/t6042-merge-rename-corner-cases.sh b/t/t6042-merge-rename-corner-cases.sh
new file mode 100755
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+++ b/t/t6042-merge-rename-corner-cases.sh
@@ -0,0 +1,578 @@
+#!/bin/sh
+
+test_description="recursive merge corner cases w/ renames but not criss-crosses"
+# t6036 has corner cases that involve both criss-cross merges and renames
+
+. ./test-lib.sh
+
+test_expect_success 'setup rename/delete + untracked file' '
+	echo "A pretty inscription" >ring &&
+	git add ring &&
+	test_tick &&
+	git commit -m beginning &&
+
+	git branch people &&
+	git checkout -b rename-the-ring &&
+	git mv ring one-ring-to-rule-them-all &&
+	test_tick &&
+	git commit -m fullname &&
+
+	git checkout people &&
+	git rm ring &&
+	echo gollum >owner &&
+	git add owner &&
+	test_tick &&
+	git commit -m track-people-instead-of-objects &&
+	echo "Myyy PRECIOUSSS" >ring
+'
+
+test_expect_success "Does git preserve Gollum's precious artifact?" '
+	test_must_fail git merge -s recursive rename-the-ring &&
+
+	# Make sure git did not delete an untracked file
+	test -f ring
+'
+
+# Testcase setup for rename/modify/add-source:
+#   Commit A: new file: a
+#   Commit B: modify a slightly
+#   Commit C: rename a->b, add completely different a
+#
+# We should be able to merge B & C cleanly
+
+test_expect_success 'setup rename/modify/add-source conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n6\n7\n" >a &&
+	git add a &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	echo 8 >>a &&
+	git add a &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv a b &&
+	echo something completely different >a &&
+	git add a &&
+	git commit -m C
+'
+
+test_expect_failure 'rename/modify/add-source conflict resolvable' '
+	git checkout B^0 &&
+
+	git merge -s recursive C^0 &&
+
+	test $(git rev-parse B:a) = $(git rev-parse b) &&
+	test $(git rev-parse C:a) = $(git rev-parse a)
+'
+
+test_expect_success 'setup resolvable conflict missed if rename missed' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n" >a &&
+	echo foo >b &&
+	git add a b &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a c &&
+	echo "Completely different content" >a &&
+	git add a &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	echo 6 >>a &&
+	git add a &&
+	git commit -m C
+'
+
+test_expect_failure 'conflict caused if rename not detected' '
+	git checkout -q C^0 &&
+	git merge -s recursive B^0 &&
+
+	test 3 -eq $(git ls-files -s | wc -l) &&
+	test 0 -eq $(git ls-files -u | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test_line_count = 6 c &&
+	test $(git rev-parse HEAD:a) = $(git rev-parse B:a) &&
+	test $(git rev-parse HEAD:b) = $(git rev-parse A:b)
+'
+
+test_expect_success 'setup conflict resolved wrong if rename missed' '
+	git reset --hard &&
+	git clean -f &&
+
+	git checkout -b D A &&
+	echo 7 >>a &&
+	git add a &&
+	git mv a c &&
+	echo "Completely different content" >a &&
+	git add a &&
+	git commit -m D &&
+
+	git checkout -b E A &&
+	git rm a &&
+	echo "Completely different content" >>a &&
+	git add a &&
+	git commit -m E
+'
+
+test_expect_failure 'missed conflict if rename not detected' '
+	git checkout -q E^0 &&
+	test_must_fail git merge -s recursive D^0
+'
+
+# Tests for undetected rename/add-source causing a file to erroneously be
+# deleted (and for mishandled rename/rename(1to1) causing the same issue).
+#
+# This test uses a rename/rename(1to1)+add-source conflict (1to1 means the
+# same file is renamed on both sides to the same thing; it should trigger
+# the 1to2 logic, which it would do if the add-source didn't cause issues
+# for git's rename detection):
+#   Commit A: new file: a
+#   Commit B: rename a->b
+#   Commit C: rename a->b, add unrelated a
+
+test_expect_success 'setup undetected rename/add-source causes data loss' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n" >a &&
+	git add a &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a b &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv a b &&
+	echo foobar >a &&
+	git add a &&
+	git commit -m C
+'
+
+test_expect_failure 'detect rename/add-source and preserve all data' '
+	git checkout B^0 &&
+
+	git merge -s recursive C^0 &&
+
+	test 2 -eq $(git ls-files -s | wc -l) &&
+	test 2 -eq $(git ls-files -u | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test -f a &&
+	test -f b &&
+
+	test $(git rev-parse HEAD:b) = $(git rev-parse A:a) &&
+	test $(git rev-parse HEAD:a) = $(git rev-parse C:a)
+'
+
+test_expect_failure 'detect rename/add-source and preserve all data, merge other way' '
+	git checkout C^0 &&
+
+	git merge -s recursive B^0 &&
+
+	test 2 -eq $(git ls-files -s | wc -l) &&
+	test 2 -eq $(git ls-files -u | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test -f a &&
+	test -f b &&
+
+	test $(git rev-parse HEAD:b) = $(git rev-parse A:a) &&
+	test $(git rev-parse HEAD:a) = $(git rev-parse C:a)
+'
+
+test_expect_success 'setup content merge + rename/directory conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n6\n" >file &&
+	git add file &&
+	test_tick &&
+	git commit -m base &&
+	git tag base &&
+
+	git checkout -b right &&
+	echo 7 >>file &&
+	mkdir newfile &&
+	echo junk >newfile/realfile &&
+	git add file newfile/realfile &&
+	test_tick &&
+	git commit -m right &&
+
+	git checkout -b left-conflict base &&
+	echo 8 >>file &&
+	git add file &&
+	git mv file newfile &&
+	test_tick &&
+	git commit -m left &&
+
+	git checkout -b left-clean base &&
+	echo 0 >newfile &&
+	cat file >>newfile &&
+	git add newfile &&
+	git rm file &&
+	test_tick &&
+	git commit -m left
+'
+
+test_expect_success 'rename/directory conflict + clean content merge' '
+	git reset --hard &&
+	git reset --hard &&
+	git clean -fdqx &&
+
+	git checkout left-clean^0 &&
+
+	test_must_fail git merge -s recursive right^0 &&
+
+	test 2 -eq $(git ls-files -s | wc -l) &&
+	test 1 -eq $(git ls-files -u | wc -l) &&
+	test 1 -eq $(git ls-files -o | wc -l) &&
+
+	echo 0 >expect &&
+	git cat-file -p base:file >>expect &&
+	echo 7 >>expect &&
+	test_cmp expect newfile~HEAD &&
+
+	test $(git rev-parse :2:newfile) = $(git hash-object expect) &&
+
+	test -f newfile/realfile &&
+	test -f newfile~HEAD
+'
+
+test_expect_success 'rename/directory conflict + content merge conflict' '
+	git reset --hard &&
+	git reset --hard &&
+	git clean -fdqx &&
+
+	git checkout left-conflict^0 &&
+
+	test_must_fail git merge -s recursive right^0 &&
+
+	test 4 -eq $(git ls-files -s | wc -l) &&
+	test 3 -eq $(git ls-files -u | wc -l) &&
+	test 1 -eq $(git ls-files -o | wc -l) &&
+
+	git cat-file -p left-conflict:newfile >left &&
+	git cat-file -p base:file    >base &&
+	git cat-file -p right:file   >right &&
+	test_must_fail git merge-file \
+		-L "HEAD:newfile" \
+		-L "" \
+		-L "right^0:file" \
+		left base right &&
+	test_cmp left newfile~HEAD &&
+
+	test $(git rev-parse :1:newfile) = $(git rev-parse base:file) &&
+	test $(git rev-parse :2:newfile) = $(git rev-parse left-conflict:newfile) &&
+	test $(git rev-parse :3:newfile) = $(git rev-parse right:file) &&
+
+	test -f newfile/realfile &&
+	test -f newfile~HEAD
+'
+
+test_expect_success 'setup content merge + rename/directory conflict w/ disappearing dir' '
+	git reset --hard &&
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	mkdir sub &&
+	printf "1\n2\n3\n4\n5\n6\n" >sub/file &&
+	git add sub/file &&
+	test_tick &&
+	git commit -m base &&
+	git tag base &&
+
+	git checkout -b right &&
+	echo 7 >>sub/file &&
+	git add sub/file &&
+	test_tick &&
+	git commit -m right &&
+
+	git checkout -b left base &&
+	echo 0 >newfile &&
+	cat sub/file >>newfile &&
+	git rm sub/file &&
+	mv newfile sub &&
+	git add sub &&
+	test_tick &&
+	git commit -m left
+'
+
+test_expect_success 'disappearing dir in rename/directory conflict handled' '
+	git reset --hard &&
+	git clean -fdqx &&
+
+	git checkout left^0 &&
+
+	git merge -s recursive right^0 &&
+
+	test 1 -eq $(git ls-files -s | wc -l) &&
+	test 0 -eq $(git ls-files -u | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	echo 0 >expect &&
+	git cat-file -p base:sub/file >>expect &&
+	echo 7 >>expect &&
+	test_cmp expect sub &&
+
+	test -f sub
+'
+
+# Test for all kinds of things that can go wrong with rename/rename (2to1):
+#   Commit A: new files: a & b
+#   Commit B: rename a->c, modify b
+#   Commit C: rename b->c, modify a
+#
+# Merging of B & C should NOT be clean.  Questions:
+#   * Both a & b should be removed by the merge; are they?
+#   * The two c's should contain modifications to a & b; do they?
+#   * The index should contain two files, both for c; does it?
+#   * The working copy should have two files, both of form c~<unique>; does it?
+#   * Nothing else should be present.  Is anything?
+
+test_expect_success 'setup rename/rename (2to1) + modify/modify' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n" >a &&
+	printf "5\n4\n3\n2\n1\n" >b &&
+	git add a b &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a c &&
+	echo 0 >>b &&
+	git add b &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv b c &&
+	echo 6 >>a &&
+	git add a &&
+	git commit -m C
+'
+
+test_expect_success 'handle rename/rename (2to1) conflict correctly' '
+	git checkout B^0 &&
+
+	test_must_fail git merge -s recursive C^0 >out &&
+	test_i18ngrep "CONFLICT (rename/rename)" out &&
+
+	test 2 -eq $(git ls-files -s | wc -l) &&
+	test 2 -eq $(git ls-files -u | wc -l) &&
+	test 2 -eq $(git ls-files -u c | wc -l) &&
+	test 3 -eq $(git ls-files -o | wc -l) &&
+
+	test ! -f a &&
+	test ! -f b &&
+	test -f c~HEAD &&
+	test -f c~C^0 &&
+
+	test $(git hash-object c~HEAD) = $(git rev-parse C:a) &&
+	test $(git hash-object c~C^0) = $(git rev-parse B:b)
+'
+
+# Testcase setup for simple rename/rename (1to2) conflict:
+#   Commit A: new file: a
+#   Commit B: rename a->b
+#   Commit C: rename a->c
+test_expect_success 'setup simple rename/rename (1to2) conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	echo stuff >a &&
+	git add a &&
+	test_tick &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a b &&
+	test_tick &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv a c &&
+	test_tick &&
+	git commit -m C
+'
+
+test_expect_success 'merge has correct working tree contents' '
+	git checkout C^0 &&
+
+	test_must_fail git merge -s recursive B^0 &&
+
+	test 3 -eq $(git ls-files -s | wc -l) &&
+	test 3 -eq $(git ls-files -u | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test $(git rev-parse :1:a) = $(git rev-parse A:a) &&
+	test $(git rev-parse :3:b) = $(git rev-parse A:a) &&
+	test $(git rev-parse :2:c) = $(git rev-parse A:a) &&
+
+	test ! -f a &&
+	test $(git hash-object b) = $(git rev-parse A:a) &&
+	test $(git hash-object c) = $(git rev-parse A:a)
+'
+
+# Testcase setup for rename/rename(1to2)/add-source conflict:
+#   Commit A: new file: a
+#   Commit B: rename a->b
+#   Commit C: rename a->c, add completely different a
+#
+# Merging of B & C should NOT be clean; there's a rename/rename conflict
+
+test_expect_success 'setup rename/rename(1to2)/add-source conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	printf "1\n2\n3\n4\n5\n6\n7\n" >a &&
+	git add a &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a b &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv a c &&
+	echo something completely different >a &&
+	git add a &&
+	git commit -m C
+'
+
+test_expect_failure 'detect conflict with rename/rename(1to2)/add-source merge' '
+	git checkout B^0 &&
+
+	test_must_fail git merge -s recursive C^0 &&
+
+	test 4 -eq $(git ls-files -s | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test $(git rev-parse 3:a) = $(git rev-parse C:a) &&
+	test $(git rev-parse 1:a) = $(git rev-parse A:a) &&
+	test $(git rev-parse 2:b) = $(git rev-parse B:b) &&
+	test $(git rev-parse 3:c) = $(git rev-parse C:c) &&
+
+	test -f a &&
+	test -f b &&
+	test -f c
+'
+
+test_expect_success 'setup rename/rename(1to2)/add-source resolvable conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	>a &&
+	git add a &&
+	test_tick &&
+	git commit -m base &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a b &&
+	test_tick &&
+	git commit -m one &&
+
+	git checkout -b C A &&
+	git mv a b &&
+	echo important-info >a &&
+	git add a &&
+	test_tick &&
+	git commit -m two
+'
+
+test_expect_failure 'rename/rename/add-source still tracks new a file' '
+	git checkout C^0 &&
+	git merge -s recursive B^0 &&
+
+	test 2 -eq $(git ls-files -s | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+
+	test $(git rev-parse HEAD:a) = $(git rev-parse C:a) &&
+	test $(git rev-parse HEAD:b) = $(git rev-parse A:a)
+'
+
+test_expect_success 'setup rename/rename(1to2)/add-dest conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	echo stuff >a &&
+	git add a &&
+	test_tick &&
+	git commit -m base &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a b &&
+	echo precious-data >c &&
+	git add c &&
+	test_tick &&
+	git commit -m one &&
+
+	git checkout -b C A &&
+	git mv a c &&
+	echo important-info >b &&
+	git add b &&
+	test_tick &&
+	git commit -m two
+'
+
+test_expect_success 'rename/rename/add-dest merge still knows about conflicting file versions' '
+	git checkout C^0 &&
+	test_must_fail git merge -s recursive B^0 &&
+
+	test 5 -eq $(git ls-files -s | wc -l) &&
+	test 2 -eq $(git ls-files -u b | wc -l) &&
+	test 2 -eq $(git ls-files -u c | wc -l) &&
+	test 4 -eq $(git ls-files -o | wc -l) &&
+
+	test $(git rev-parse :1:a) = $(git rev-parse A:a) &&
+	test $(git rev-parse :2:b) = $(git rev-parse C:b) &&
+	test $(git rev-parse :3:b) = $(git rev-parse B:b) &&
+	test $(git rev-parse :2:c) = $(git rev-parse C:c) &&
+	test $(git rev-parse :3:c) = $(git rev-parse B:c) &&
+
+	test $(git hash-object c~HEAD) = $(git rev-parse C:c) &&
+	test $(git hash-object c~B\^0) = $(git rev-parse B:c) &&
+	test $(git hash-object b~HEAD) = $(git rev-parse C:b) &&
+	test $(git hash-object b~B\^0) = $(git rev-parse B:b) &&
+
+	test ! -f b &&
+	test ! -f c
+'
+
+test_done