[PATCH v2 1/2] t1015: demonstrate directory/file conflict recovery failures

[Elijah Newren <newren@gmail.com>]

Several "recovery" commands outright fail or do not fully recover
when directory-file conflicts are present.  This includes:
  * git read-tree --reset HEAD
  * git am --skip
  * git am --abort
  * git merge --abort
  * git reset --hard

Add testcases documenting these shortcomings.

Signed-off-by: Elijah Newren <newren@gmail.com>
---
 t/t1015-read-index-unmerged.sh | 123 +++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100755 t/t1015-read-index-unmerged.sh

diff --git a/t/t1015-read-index-unmerged.sh b/t/t1015-read-index-unmerged.sh
new file mode 100755
index 0000000000..32ef6bdcfa
--- /dev/null
+++ b/t/t1015-read-index-unmerged.sh
@@ -0,0 +1,123 @@
+#!/bin/sh
+
+test_description='Test various callers of read_index_unmerged'
+. ./test-lib.sh
+
+test_expect_success 'setup modify/delete + directory/file conflict' '
+	test_create_repo df_plus_modify_delete &&
+	(
+		cd df_plus_modify_delete &&
+
+		test_write_lines a b c d e f g h >letters &&
+		git add letters &&
+		git commit -m initial &&
+
+		git checkout -b modify &&
+		# Throw in letters.txt for sorting order fun
+		# ("letters.txt" sorts between "letters" and "letters/file")
+		echo i >>letters &&
+		echo "version 2" >letters.txt &&
+		git add letters letters.txt &&
+		git commit -m modified &&
+
+		git checkout -b delete HEAD^ &&
+		git rm letters &&
+		mkdir letters &&
+		>letters/file &&
+		echo "version 1" >letters.txt &&
+		git add letters letters.txt &&
+		git commit -m deleted
+	)
+'
+
+test_expect_failure 'read-tree --reset cleans unmerged entries' '
+	test_when_finished "git -C df_plus_modify_delete clean -f" &&
+	test_when_finished "git -C df_plus_modify_delete reset --hard" &&
+	(
+		cd df_plus_modify_delete &&
+
+		git checkout delete^0 &&
+		test_must_fail git merge modify &&
+
+		git read-tree --reset HEAD &&
+		git ls-files -u >conflicts &&
+		test_must_be_empty conflicts
+	)
+'
+
+test_expect_failure 'One reset --hard cleans unmerged entries' '
+	test_when_finished "git -C df_plus_modify_delete clean -f" &&
+	test_when_finished "git -C df_plus_modify_delete reset --hard" &&
+	(
+		cd df_plus_modify_delete &&
+
+		git checkout delete^0 &&
+		test_must_fail git merge modify &&
+
+		git reset --hard &&
+		test_path_is_missing .git/MERGE_HEAD &&
+		git ls-files -u >conflicts &&
+		test_must_be_empty conflicts
+	)
+'
+
+test_expect_success 'setup directory/file conflict + simple edit/edit' '
+	test_create_repo df_plus_edit_edit &&
+	(
+		cd df_plus_edit_edit &&
+
+		test_seq 1 10 >numbers &&
+		git add numbers &&
+		git commit -m initial &&
+
+		git checkout -b d-edit &&
+		mkdir foo &&
+		echo content >foo/bar &&
+		git add foo &&
+		echo 11 >>numbers &&
+		git add numbers &&
+		git commit -m "directory and edit" &&
+
+		git checkout -b f-edit d-edit^1 &&
+		echo content >foo &&
+		git add foo &&
+		echo eleven >>numbers &&
+		git add numbers &&
+		git commit -m "file and edit"
+	)
+'
+
+test_expect_failure 'git merge --abort succeeds despite D/F conflict' '
+	test_when_finished "git -C df_plus_edit_edit clean -f" &&
+	test_when_finished "git -C df_plus_edit_edit reset --hard" &&
+	(
+		cd df_plus_edit_edit &&
+
+		git checkout f-edit^0 &&
+		test_must_fail git merge d-edit^0 &&
+
+		git merge --abort &&
+		test_path_is_missing .git/MERGE_HEAD &&
+		git ls-files -u >conflicts &&
+		test_must_be_empty conflicts
+	)
+'
+
+test_expect_failure 'git am --skip succeeds despite D/F conflict' '
+	test_when_finished "git -C df_plus_edit_edit clean -f" &&
+	test_when_finished "git -C df_plus_edit_edit reset --hard" &&
+	(
+		cd df_plus_edit_edit &&
+
+		git checkout f-edit^0 &&
+		git format-patch -1 d-edit &&
+		test_must_fail git am -3 0001*.patch &&
+
+		git am --skip &&
+		test_path_is_missing .git/rebase-apply &&
+		git ls-files -u >conflicts &&
+		test_must_be_empty conflicts
+	)
+'
+
+test_done
-- 
2.18.0.645.g72fe132ec2