[PATCH 1/2] t6042: Add failing test for rename/rename/delete/delete.

[Nicolas Cavallari <nicolas.cavallari@green-communications.fr>]

Each side of a rename 2to1 could also be deleted by the other side.
The code does not expect this.  While it luckily works for files,
it fails for symlinks as follow:

CONFLICT (rename/rename): Rename a->c in HEAD. Rename b->c in C^0
Renaming a to c~HEAD and b to c~C^0 instead
error: cannot read object 0000000000000000000000000000000000000000 'c~C^0'

Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
---
 t/t6042-merge-rename-corner-cases.sh | 38 ++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/t/t6042-merge-rename-corner-cases.sh b/t/t6042-merge-rename-corner-cases.sh
index 411550d2b..ea4e14cbd 100755
--- a/t/t6042-merge-rename-corner-cases.sh
+++ b/t/t6042-merge-rename-corner-cases.sh
@@ -575,4 +575,42 @@ test_expect_success 'rename/rename/add-dest merge still knows about conflicting
 	test ! -f c
 '
 
+# Testcase setup for rename/rename/delete/delete (2in1, deleted):
+#   Commit A: new symlinks: a->alice b->bob
+#   Commit B: rename a->c, delete b
+#   Commit C: rename b->c, delete a
+#
+# We should not fail completely.
+
+test_expect_success 'setup rename/rename/delete/delete conflict' '
+	git rm -rf . &&
+	git clean -fdqx &&
+	rm -rf .git &&
+	git init &&
+
+	ln -s alice a &&
+	ln -s bob b &&
+	git add a b &&
+	git commit -m A &&
+	git tag A &&
+
+	git checkout -b B A &&
+	git mv a c &&
+	git rm b &&
+	git commit -m B &&
+
+	git checkout -b C A &&
+	git mv b c &&
+	git rm a &&
+	git commit -m C
+'
+
+test_expect_failure 'rename/rename/delete/delete leaves at least one file' '
+	git checkout B^0 &&
+	test_must_fail git merge -s recursive C^0 &&
+
+	test -L "c~HEAD" &&
+	test -L "c~C^0"
+'
+
 test_done
-- 
2.11.0