Merge branch 'en/d-f-conflict-fix'

* en/d-f-conflict-fix:
  merge-recursive: Avoid excessive output for and reprocessing of renames
  merge-recursive: Fix multiple file rename across D/F conflict
  t6031: Add a testcase covering multiple renames across a D/F conflict
  merge-recursive: Fix typo
  Mark tests that use symlinks as needing SYMLINKS prerequisite
  t/t6035-merge-dir-to-symlink.sh: Remove TODO on passing test
  fast-import: Improve robustness when D->F changes provided in wrong order
  fast-export: Fix output order of D/F changes
  merge_recursive: Fix renames across paths below D/F conflicts
  merge-recursive: Fix D/F conflicts
  Add a rename + D/F conflict testcase
  Add additional testcases for D/F conflicts

Conflicts:
	merge-recursive.c

5 files changed, 151 insertions, 5 deletions

diff --git a/t/t3509-cherry-pick-merge-df.sh b/t/t3509-cherry-pick-merge-df.sh
new file mode 100755
index 0000000000..a5ccdbf8fc
--- /dev/null
+++ b/t/t3509-cherry-pick-merge-df.sh
@@ -0,0 +1,35 @@
+#!/bin/sh
+
+test_description='Test cherry-pick with directory/file conflicts'
+. ./test-lib.sh
+
+test_expect_success SYMLINKS 'Setup rename across paths each below D/F conflicts' '
+	mkdir a &&
+	>a/f &&
+	git add a &&
+	git commit -m a &&
+
+	mkdir b &&
+	ln -s ../a b/a &&
+	git add b &&
+	git commit -m b &&
+
+	git checkout -b branch &&
+	rm b/a &&
+	mv a b/a &&
+	ln -s b/a a &&
+	git add . &&
+	git commit -m swap &&
+
+	>f1 &&
+	git add f1 &&
+	git commit -m f1
+'
+
+test_expect_success SYMLINKS 'Cherry-pick succeeds with rename across D/F conflicts' '
+	git reset --hard &&
+	git checkout master^0 &&
+	git cherry-pick branch
+'
+
+test_done
diff --git a/t/t6020-merge-df.sh b/t/t6020-merge-df.sh
index e71c687f2b..490d397114 100755
--- a/t/t6020-merge-df.sh
+++ b/t/t6020-merge-df.sh
@@ -22,7 +22,7 @@ git commit -m "File: dir"'
 
 test_expect_code 1 'Merge with d/f conflicts' 'git merge "merge msg" B master'
 
-test_expect_failure 'F/D conflict' '
+test_expect_success 'F/D conflict' '
 	git reset --hard &&
 	git checkout master &&
 	rm .git/index &&
diff --git a/t/t6031-merge-recursive.sh b/t/t6031-merge-recursive.sh
index 8a3304fb0b..bd75e0e643 100755
--- a/t/t6031-merge-recursive.sh
+++ b/t/t6031-merge-recursive.sh
@@ -57,4 +57,35 @@ test_expect_success FILEMODE 'verify executable bit on file' '
 	test -x file2
 '
 
+test_expect_success 'merging with triple rename across D/F conflict' '
+	git reset --hard HEAD &&
+	git checkout -b main &&
+	git rm -rf . &&
+
+	echo "just a file" >sub1 &&
+	mkdir -p sub2 &&
+	echo content1 >sub2/file1 &&
+	echo content2 >sub2/file2 &&
+	echo content3 >sub2/file3 &&
+	mkdir simple &&
+	echo base >simple/bar &&
+	git add -A &&
+	test_tick &&
+	git commit -m base &&
+
+	git checkout -b other &&
+	echo more >>simple/bar &&
+	test_tick &&
+	git commit -a -m changesimplefile &&
+
+	git checkout main &&
+	git rm sub1 &&
+	git mv sub2 sub1 &&
+	test_tick &&
+	git commit -m changefiletodir &&
+
+	test_tick &&
+	git merge other
+'
+
 test_done
diff --git a/t/t6035-merge-dir-to-symlink.sh b/t/t6035-merge-dir-to-symlink.sh
index cd3190c4a6..dc09513be5 100755
--- a/t/t6035-merge-dir-to-symlink.sh
+++ b/t/t6035-merge-dir-to-symlink.sh
@@ -48,7 +48,7 @@ test_expect_success 'setup for merge test' '
 	git tag baseline
 '
 
-test_expect_success 'do not lose a/b-2/c/d in merge (resolve)' '
+test_expect_success 'Handle D/F conflict, do not lose a/b-2/c/d in merge (resolve)' '
 	git reset --hard &&
 	git checkout baseline^0 &&
 	git merge -s resolve master &&
@@ -56,7 +56,7 @@ test_expect_success 'do not lose a/b-2/c/d in merge (resolve)' '
 	test -f a/b-2/c/d
 '
 
-test_expect_failure 'do not lose a/b-2/c/d in merge (recursive)' '
+test_expect_success 'Handle D/F conflict, do not lose a/b-2/c/d in merge (recursive)' '
 	git reset --hard &&
 	git checkout baseline^0 &&
 	git merge -s recursive master &&
@@ -64,6 +64,54 @@ test_expect_failure 'do not lose a/b-2/c/d in merge (recursive)' '
 	test -f a/b-2/c/d
 '
 
+test_expect_success 'Handle F/D conflict, do not lose a/b-2/c/d in merge (resolve)' '
+	git reset --hard &&
+	git checkout master^0 &&
+	git merge -s resolve baseline^0 &&
+	test -h a/b &&
+	test -f a/b-2/c/d
+'
+
+test_expect_success 'Handle F/D conflict, do not lose a/b-2/c/d in merge (recursive)' '
+	git reset --hard &&
+	git checkout master^0 &&
+	git merge -s recursive baseline^0 &&
+	test -h a/b &&
+	test -f a/b-2/c/d
+'
+
+test_expect_failure 'do not lose untracked in merge (resolve)' '
+	git reset --hard &&
+	git checkout baseline^0 &&
+	>a/b/c/e &&
+	test_must_fail git merge -s resolve master &&
+	test -f a/b/c/e &&
+	test -f a/b-2/c/d
+'
+
+test_expect_success 'do not lose untracked in merge (recursive)' '
+	git reset --hard &&
+	git checkout baseline^0 &&
+	>a/b/c/e &&
+	test_must_fail git merge -s recursive master &&
+	test -f a/b/c/e &&
+	test -f a/b-2/c/d
+'
+
+test_expect_success 'do not lose modifications in merge (resolve)' '
+	git reset --hard &&
+	git checkout baseline^0 &&
+	echo more content >>a/b/c/d &&
+	test_must_fail git merge -s resolve master
+'
+
+test_expect_success 'do not lose modifications in merge (recursive)' '
+	git reset --hard &&
+	git checkout baseline^0 &&
+	echo more content >>a/b/c/d &&
+	test_must_fail git merge -s recursive master
+'
+
 test_expect_success 'setup a merge where dir a/b-2 changed to symlink' '
 	git reset --hard &&
 	git checkout start^0 &&
@@ -74,7 +122,7 @@ test_expect_success 'setup a merge where dir a/b-2 changed to symlink' '
 	git tag test2
 '
 
-test_expect_success 'merge should not have conflicts (resolve)' '
+test_expect_success 'merge should not have D/F conflicts (resolve)' '
 	git reset --hard &&
 	git checkout baseline^0 &&
 	git merge -s resolve test2 &&
@@ -82,7 +130,7 @@ test_expect_success 'merge should not have conflicts (resolve)' '
 	test -f a/b/c/d
 '
 
-test_expect_failure 'merge should not have conflicts (recursive)' '
+test_expect_success 'merge should not have D/F conflicts (recursive)' '
 	git reset --hard &&
 	git checkout baseline^0 &&
 	git merge -s recursive test2 &&
@@ -90,4 +138,12 @@ test_expect_failure 'merge should not have conflicts (recursive)' '
 	test -f a/b/c/d
 '
 
+test_expect_success 'merge should not have F/D conflicts (recursive)' '
+	git reset --hard &&
+	git checkout -b foo test2 &&
+	git merge -s recursive baseline^0 &&
+	test -h a/b-2 &&
+	test -f a/b/c/d
+'
+
 test_done
diff --git a/t/t9350-fast-export.sh b/t/t9350-fast-export.sh
index d831404fba..8c8e679468 100755
--- a/t/t9350-fast-export.sh
+++ b/t/t9350-fast-export.sh
@@ -390,4 +390,28 @@ test_expect_success 'tree_tag-obj'    'git fast-export tree_tag-obj'
 test_expect_success 'tag-obj_tag'     'git fast-export tag-obj_tag'
 test_expect_success 'tag-obj_tag-obj' 'git fast-export tag-obj_tag-obj'
 
+test_expect_success SYMLINKS 'directory becomes symlink'        '
+	git init dirtosymlink &&
+	git init result &&
+	(
+		cd dirtosymlink &&
+		mkdir foo &&
+		mkdir bar &&
+		echo hello > foo/world &&
+		echo hello > bar/world &&
+		git add foo/world bar/world &&
+		git commit -q -mone &&
+		git rm -r foo &&
+		ln -s bar foo &&
+		git add foo &&
+		git commit -q -mtwo
+	) &&
+	(
+		cd dirtosymlink &&
+		git fast-export master -- foo |
+		(cd ../result && git fast-import --quiet)
+	) &&
+	(cd result && git show master:foo)
+'
+
 test_done