merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

2 files changed, 1120 insertions, 0 deletions

diff --git a/third_party/git/contrib/subtree/t/Makefile b/third_party/git/contrib/subtree/t/Makefile
new file mode 100644
index 000000000000..276898eb6bd7
--- /dev/null
+++ b/third_party/git/contrib/subtree/t/Makefile
@@ -0,0 +1,86 @@
+# Run tests
+#
+# Copyright (c) 2005 Junio C Hamano
+#
+
+-include ../../../config.mak.autogen
+-include ../../../config.mak
+
+#GIT_TEST_OPTS=--verbose --debug
+SHELL_PATH ?= $(SHELL)
+PERL_PATH ?= /usr/bin/perl
+TAR ?= $(TAR)
+RM ?= rm -f
+PROVE ?= prove
+DEFAULT_TEST_TARGET ?= test
+TEST_LINT ?= test-lint
+
+ifdef TEST_OUTPUT_DIRECTORY
+TEST_RESULTS_DIRECTORY = $(TEST_OUTPUT_DIRECTORY)/test-results
+else
+TEST_RESULTS_DIRECTORY = ../../../t/test-results
+endif
+
+# Shell quote;
+SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
+PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH))
+TEST_RESULTS_DIRECTORY_SQ = $(subst ','\'',$(TEST_RESULTS_DIRECTORY))
+
+T = $(sort $(wildcard t[0-9][0-9][0-9][0-9]-*.sh))
+TSVN = $(sort $(wildcard t91[0-9][0-9]-*.sh))
+TGITWEB = $(sort $(wildcard t95[0-9][0-9]-*.sh))
+THELPERS = $(sort $(filter-out $(T),$(wildcard *.sh)))
+
+all: $(DEFAULT_TEST_TARGET)
+
+test: pre-clean $(TEST_LINT)
+	$(MAKE) aggregate-results-and-cleanup
+
+prove: pre-clean $(TEST_LINT)
+	@echo "*** prove ***"; GIT_CONFIG=.git/config $(PROVE) --exec '$(SHELL_PATH_SQ)' $(GIT_PROVE_OPTS) $(T) :: $(GIT_TEST_OPTS)
+	$(MAKE) clean-except-prove-cache
+
+$(T):
+	@echo "*** $@ ***"; GIT_CONFIG=.git/config '$(SHELL_PATH_SQ)' $@ $(GIT_TEST_OPTS)
+
+pre-clean:
+	$(RM) -r '$(TEST_RESULTS_DIRECTORY_SQ)'
+
+clean-except-prove-cache:
+	$(RM) -r 'trash directory'.* '$(TEST_RESULTS_DIRECTORY_SQ)'
+	$(RM) -r valgrind/bin
+
+clean: clean-except-prove-cache
+	$(RM) .prove
+
+test-lint: test-lint-duplicates test-lint-executable test-lint-shell-syntax
+
+test-lint-duplicates:
+	@dups=`echo $(T) | tr ' ' '\n' | sed 's/-.*//' | sort | uniq -d` && \
+		test -z "$$dups" || { \
+		echo >&2 "duplicate test numbers:" $$dups; exit 1; }
+
+test-lint-executable:
+	@bad=`for i in $(T); do test -x "$$i" || echo $$i; done` && \
+		test -z "$$bad" || { \
+		echo >&2 "non-executable tests:" $$bad; exit 1; }
+
+test-lint-shell-syntax:
+	@'$(PERL_PATH_SQ)' ../../../t/check-non-portable-shell.pl $(T) $(THELPERS)
+
+aggregate-results-and-cleanup: $(T)
+	$(MAKE) aggregate-results
+	$(MAKE) clean
+
+aggregate-results:
+	for f in '$(TEST_RESULTS_DIRECTORY_SQ)'/t*-*.counts; do \
+		echo "$$f"; \
+	done | '$(SHELL_PATH_SQ)' ../../../t/aggregate-results.sh
+
+valgrind:
+	$(MAKE) GIT_TEST_OPTS="$(GIT_TEST_OPTS) --valgrind"
+
+test-results:
+	mkdir -p test-results
+
+.PHONY: pre-clean $(T) aggregate-results clean valgrind
diff --git a/third_party/git/contrib/subtree/t/t7900-subtree.sh b/third_party/git/contrib/subtree/t/t7900-subtree.sh
new file mode 100755
index 000000000000..57ff4b25c17e
--- /dev/null
+++ b/third_party/git/contrib/subtree/t/t7900-subtree.sh
@@ -0,0 +1,1034 @@
+#!/bin/sh
+#
+# Copyright (c) 2012 Avery Pennaraum
+# Copyright (c) 2015 Alexey Shumkin
+#
+test_description='Basic porcelain support for subtrees
+
+This test verifies the basic operation of the add, pull, merge
+and split subcommands of git subtree.
+'
+
+TEST_DIRECTORY=$(pwd)/../../../t
+export TEST_DIRECTORY
+
+. ../../../t/test-lib.sh
+
+subtree_test_create_repo()
+{
+	test_create_repo "$1" &&
+	(
+		cd "$1" &&
+		git config log.date relative
+	)
+}
+
+create()
+{
+	echo "$1" >"$1" &&
+	git add "$1"
+}
+
+check_equal()
+{
+	test_debug 'echo'
+	test_debug "echo \"check a:\" \"{$1}\""
+	test_debug "echo \"      b:\" \"{$2}\""
+	if [ "$1" = "$2" ]; then
+		return 0
+	else
+		return 1
+	fi
+}
+
+undo()
+{
+	git reset --hard HEAD~
+}
+
+# Make sure no patch changes more than one file.
+# The original set of commits changed only one file each.
+# A multi-file change would imply that we pruned commits
+# too aggressively.
+join_commits()
+{
+	commit=
+	all=
+	while read x y; do
+		if [ -z "$x" ]; then
+			continue
+		elif [ "$x" = "commit:" ]; then
+			if [ -n "$commit" ]; then
+				echo "$commit $all"
+				all=
+			fi
+			commit="$y"
+		else
+			all="$all $y"
+		fi
+	done
+	echo "$commit $all"
+}
+
+test_create_commit() (
+	repo=$1 &&
+	commit=$2 &&
+	cd "$repo" &&
+	mkdir -p "$(dirname "$commit")" \
+	|| error "Could not create directory for commit"
+	echo "$commit" >"$commit" &&
+	git add "$commit" || error "Could not add commit"
+	git commit -m "$commit" || error "Could not commit"
+)
+
+last_commit_message()
+{
+	git log --pretty=format:%s -1
+}
+
+subtree_test_count=0
+next_test() {
+	subtree_test_count=$(($subtree_test_count+1))
+}
+
+#
+# Tests for 'git subtree add'
+#
+
+next_test
+test_expect_success 'no merge from non-existent subtree' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		test_must_fail git subtree merge --prefix="sub dir" FETCH_HEAD
+	)
+'
+
+next_test
+test_expect_success 'no pull from non-existent subtree' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		test_must_fail git subtree pull --prefix="sub dir" ./"sub proj" master
+	)'
+
+next_test
+test_expect_success 'add subproj as subtree into sub dir/ with --prefix' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Add '\''sub dir/'\'' from commit '\''$(git rev-parse FETCH_HEAD)'\''"
+	)
+'
+
+next_test
+test_expect_success 'add subproj as subtree into sub dir/ with --prefix and --message' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" --message="Added subproject" FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Added subproject"
+	)
+'
+
+next_test
+test_expect_success 'add subproj as subtree into sub dir/ with --prefix as -P and --message as -m' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add -P "sub dir" -m "Added subproject" FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Added subproject"
+	)
+'
+
+next_test
+test_expect_success 'add subproj as subtree into sub dir/ with --squash and --prefix and --message' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" --message="Added subproject with squash" --squash FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Added subproject with squash"
+	)
+'
+
+#
+# Tests for 'git subtree merge'
+#
+
+next_test
+test_expect_success 'merge new subproj history into sub dir/ with --prefix' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Merge commit '\''$(git rev-parse FETCH_HEAD)'\''"
+	)
+'
+
+next_test
+test_expect_success 'merge new subproj history into sub dir/ with --prefix and --message' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" --message="Merged changes from subproject" FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Merged changes from subproject"
+	)
+'
+
+next_test
+test_expect_success 'merge new subproj history into sub dir/ with --squash and --prefix and --message' '
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	subtree_test_create_repo "$subtree_test_count" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" --message="Merged changes from subproject using squash" --squash FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Merged changes from subproject using squash"
+	)
+'
+
+next_test
+test_expect_success 'merge the added subproj again, should do nothing' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD &&
+		# this shouldn not actually do anything, since FETCH_HEAD
+		# is already a parent
+		result=$(git merge -s ours -m "merge -s -ours" FETCH_HEAD) &&
+		check_equal "${result}" "Already up to date."
+	)
+'
+
+next_test
+test_expect_success 'merge new subproj history into subdir/ with a slash appended to the argument of --prefix' '
+	test_create_repo "$test_count" &&
+	test_create_repo "$test_count/subproj" &&
+	test_create_commit "$test_count" main1 &&
+	test_create_commit "$test_count/subproj" sub1 &&
+	(
+		cd "$test_count" &&
+		git fetch ./subproj master &&
+		git subtree add --prefix=subdir/ FETCH_HEAD
+	) &&
+	test_create_commit "$test_count/subproj" sub2 &&
+	(
+		cd "$test_count" &&
+		git fetch ./subproj master &&
+		git subtree merge --prefix=subdir/ FETCH_HEAD &&
+		check_equal "$(last_commit_message)" "Merge commit '\''$(git rev-parse FETCH_HEAD)'\''"
+	)
+'
+
+#
+# Tests for 'git subtree split'
+#
+
+next_test
+test_expect_success 'split requires option --prefix' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD &&
+		echo "You must provide the --prefix option." > expected &&
+		test_must_fail git subtree split > actual 2>&1 &&
+		test_debug "printf '"expected: "'" &&
+		test_debug "cat expected" &&
+		test_debug "printf '"actual: "'" &&
+		test_debug "cat actual" &&
+		test_cmp expected actual
+	)
+'
+
+next_test
+test_expect_success 'split requires path given by option --prefix must exist' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD &&
+		echo "'\''non-existent-directory'\'' does not exist; use '\''git subtree add'\''" > expected &&
+		test_must_fail git subtree split --prefix=non-existent-directory > actual 2>&1 &&
+		test_debug "printf '"expected: "'" &&
+		test_debug "cat expected" &&
+		test_debug "printf '"actual: "'" &&
+		test_debug "cat actual" &&
+		test_cmp expected actual
+	)
+'
+
+next_test
+test_expect_success 'split sub dir/ with --rejoin' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		split_hash=$(git subtree split --prefix="sub dir" --annotate="*") &&
+		git subtree split --prefix="sub dir" --annotate="*" --rejoin &&
+		check_equal "$(last_commit_message)" "Split '\''sub dir/'\'' into commit '\''$split_hash'\''"
+	)
+ '
+
+next_test
+test_expect_success 'split sub dir/ with --rejoin from scratch' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	(
+		cd "$subtree_test_count" &&
+		mkdir "sub dir" &&
+		echo file >"sub dir"/file &&
+		git add "sub dir/file" &&
+		git commit -m"sub dir file" &&
+		split_hash=$(git subtree split --prefix="sub dir" --rejoin) &&
+		git subtree split --prefix="sub dir" --rejoin &&
+		check_equal "$(last_commit_message)" "Split '\''sub dir/'\'' into commit '\''$split_hash'\''"
+	)
+ '
+
+next_test
+test_expect_success 'split sub dir/ with --rejoin and --message' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --message="Split & rejoin" --annotate="*" --rejoin &&
+		check_equal "$(last_commit_message)" "Split & rejoin"
+	)
+'
+
+next_test
+test_expect_success 'split "sub dir"/ with --branch' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		split_hash=$(git subtree split --prefix="sub dir" --annotate="*") &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br &&
+		check_equal "$(git rev-parse subproj-br)" "$split_hash"
+	)
+'
+
+next_test
+test_expect_success 'check hash of split' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		split_hash=$(git subtree split --prefix="sub dir" --annotate="*") &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br &&
+		check_equal "$(git rev-parse subproj-br)" "$split_hash" &&
+		# Check hash of split
+		new_hash=$(git rev-parse subproj-br^2) &&
+		(
+			cd ./"sub proj" &&
+			subdir_hash=$(git rev-parse HEAD) &&
+			check_equal ''"$new_hash"'' "$subdir_hash"
+		)
+	)
+'
+
+next_test
+test_expect_success 'split "sub dir"/ with --branch for an existing branch' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git branch subproj-br FETCH_HEAD &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		split_hash=$(git subtree split --prefix="sub dir" --annotate="*") &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br &&
+		check_equal "$(git rev-parse subproj-br)" "$split_hash"
+	)
+'
+
+next_test
+test_expect_success 'split "sub dir"/ with --branch for an incompatible branch' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git branch init HEAD &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		test_must_fail git subtree split --prefix="sub dir" --branch init
+	)
+'
+
+#
+# Validity checking
+#
+
+next_test
+test_expect_success 'make sure exactly the right set of files ends up in the subproj' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD &&
+
+		test_write_lines main-sub1 main-sub2 main-sub3 main-sub4 \
+			sub1 sub2 sub3 sub4 >expect &&
+		git ls-files >actual &&
+		test_cmp expect actual
+	)
+'
+
+next_test
+test_expect_success 'make sure the subproj *only* contains commits that affect the "sub dir"' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD &&
+
+		test_write_lines main-sub1 main-sub2 main-sub3 main-sub4 \
+			sub1 sub2 sub3 sub4 >expect &&
+		git log --name-only --pretty=format:"" >log &&
+		sort <log | sed "/^\$/ d" >actual &&
+		test_cmp expect actual
+	)
+'
+
+next_test
+test_expect_success 'make sure exactly the right set of files ends up in the mainline' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree pull --prefix="sub dir" ./"sub proj" master &&
+
+		test_write_lines main1 main2 >chkm &&
+		test_write_lines main-sub1 main-sub2 main-sub3 main-sub4 >chkms &&
+		sed "s,^,sub dir/," chkms >chkms_sub &&
+		test_write_lines sub1 sub2 sub3 sub4 >chks &&
+		sed "s,^,sub dir/," chks >chks_sub &&
+
+		cat chkm chkms_sub chks_sub >expect &&
+		git ls-files >actual &&
+		test_cmp expect actual
+	)
+'
+
+next_test
+test_expect_success 'make sure each filename changed exactly once in the entire history' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git config log.date relative &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree pull --prefix="sub dir" ./"sub proj" master &&
+
+		test_write_lines main1 main2 >chkm &&
+		test_write_lines sub1 sub2 sub3 sub4 >chks &&
+		test_write_lines main-sub1 main-sub2 main-sub3 main-sub4 >chkms &&
+		sed "s,^,sub dir/," chkms >chkms_sub &&
+
+		# main-sub?? and /"sub dir"/main-sub?? both change, because those are the
+		# changes that were split into their own history.  And "sub dir"/sub?? never
+		# change, since they were *only* changed in the subtree branch.
+		git log --name-only --pretty=format:"" >log &&
+		sort <log >sorted-log &&
+		sed "/^$/ d" sorted-log >actual &&
+
+		cat chkms chkm chks chkms_sub >expect-unsorted &&
+		sort expect-unsorted >expect &&
+		test_cmp expect actual
+	)
+'
+
+next_test
+test_expect_success 'make sure the --rejoin commits never make it into subproj' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree pull --prefix="sub dir" ./"sub proj" master &&
+		check_equal "$(git log --pretty=format:"%s" HEAD^2 | grep -i split)" ""
+	)
+'
+
+next_test
+test_expect_success 'make sure no "git subtree" tagged commits make it into subproj' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub3 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		 git merge FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub4 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --annotate="*" --branch subproj-br --rejoin
+	) &&
+	(
+		cd "$subtree_test_count/sub proj" &&
+		git fetch .. subproj-br &&
+		git merge FETCH_HEAD
+	) &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree pull --prefix="sub dir" ./"sub proj" master &&
+
+		# They are meaningless to subproj since one side of the merge refers to the mainline
+		check_equal "$(git log --pretty=format:"%s%n%b" HEAD^2 | grep "git-subtree.*:")" ""
+	)
+'
+
+#
+# A new set of tests
+#
+
+next_test
+test_expect_success 'make sure "git subtree split" find the correct parent' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git branch subproj-ref FETCH_HEAD &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --branch subproj-br &&
+
+		# at this point, the new commit parent should be subproj-ref, if it is
+		# not, something went wrong (the "newparent" of "master~" commit should
+		# have been sub2, but it was not, because its cache was not set to
+		# itself)
+		check_equal "$(git log --pretty=format:%P -1 subproj-br)" "$(git rev-parse subproj-ref)"
+	)
+'
+
+next_test
+test_expect_success 'split a new subtree without --onto option' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --branch subproj-br
+	) &&
+	mkdir "$subtree_test_count"/"sub dir2" &&
+	test_create_commit "$subtree_test_count" "sub dir2"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+
+		# also test that we still can split out an entirely new subtree
+		# if the parent of the first commit in the tree is not empty,
+		# then the new subtree has accidentally been attached to something
+		git subtree split --prefix="sub dir2" --branch subproj2-br &&
+		check_equal "$(git log --pretty=format:%P -1 subproj2-br)" ""
+	)
+'
+
+next_test
+test_expect_success 'verify one file change per commit' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git branch sub1 FETCH_HEAD &&
+		git subtree add --prefix="sub dir" sub1
+	) &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir" --branch subproj-br
+	) &&
+	mkdir "$subtree_test_count"/"sub dir2" &&
+	test_create_commit "$subtree_test_count" "sub dir2"/main-sub2 &&
+	(
+		cd "$subtree_test_count" &&
+		git subtree split --prefix="sub dir2" --branch subproj2-br &&
+
+		x= &&
+		git log --pretty=format:"commit: %H" | join_commits |
+		(
+			while read commit a b; do
+				test_debug "echo Verifying commit $commit"
+				test_debug "echo a: $a"
+				test_debug "echo b: $b"
+				check_equal "$b" ""
+				x=1
+			done
+			check_equal "$x" 1
+		)
+	)
+'
+
+next_test
+test_expect_success 'push split to subproj' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	subtree_test_create_repo "$subtree_test_count/sub proj" &&
+	test_create_commit "$subtree_test_count" main1 &&
+	test_create_commit "$subtree_test_count/sub proj" sub1 &&
+	(
+		cd "$subtree_test_count" &&
+		git fetch ./"sub proj" master &&
+		git subtree add --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub1 &&
+	test_create_commit "$subtree_test_count" main2 &&
+	test_create_commit "$subtree_test_count/sub proj" sub2 &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub2 &&
+	(
+		cd $subtree_test_count/"sub proj" &&
+                git branch sub-branch-1 &&
+                cd .. &&
+		git fetch ./"sub proj" master &&
+		git subtree merge --prefix="sub dir" FETCH_HEAD
+	) &&
+	test_create_commit "$subtree_test_count" "sub dir"/main-sub3 &&
+        (
+		cd "$subtree_test_count" &&
+	        git subtree push ./"sub proj" --prefix "sub dir" sub-branch-1 &&
+                cd ./"sub proj" &&
+                git checkout sub-branch-1 &&
+         	check_equal "$(last_commit_message)" "sub dir/main-sub3"
+	)
+'
+
+#
+# This test covers 2 cases in subtree split copy_or_skip code
+# 1) Merges where one parent is a superset of the changes of the other
+#    parent regarding changes to the subtree, in this case the merge
+#    commit should be copied
+# 2) Merges where only one parent operate on the subtree, and the merge
+#    commit should be skipped
+#
+# (1) is checked by ensuring subtree_tip is a descendent of subtree_branch
+# (2) should have a check added (not_a_subtree_change shouldn't be present
+#     on the produced subtree)
+#
+# Other related cases which are not tested (or currently handled correctly)
+# - Case (1) where there are more than 2 parents, it will sometimes correctly copy
+#   the merge, and sometimes not
+# - Merge commit where both parents have same tree as the merge, currently
+#   will always be skipped, even if they reached that state via different
+#   set of commits.
+#
+
+next_test
+test_expect_success 'subtree descendant check' '
+	subtree_test_create_repo "$subtree_test_count" &&
+	test_create_commit "$subtree_test_count" folder_subtree/a &&
+	(
+		cd "$subtree_test_count" &&
+		git branch branch
+	) &&
+	test_create_commit "$subtree_test_count" folder_subtree/0 &&
+	test_create_commit "$subtree_test_count" folder_subtree/b &&
+	cherry=$(cd "$subtree_test_count"; git rev-parse HEAD) &&
+	(
+		cd "$subtree_test_count" &&
+		git checkout branch
+	) &&
+	test_create_commit "$subtree_test_count" commit_on_branch &&
+	(
+		cd "$subtree_test_count" &&
+		git cherry-pick $cherry &&
+		git checkout master &&
+		git merge -m "merge should be kept on subtree" branch &&
+		git branch no_subtree_work_branch
+	) &&
+	test_create_commit "$subtree_test_count" folder_subtree/d &&
+	(
+		cd "$subtree_test_count" &&
+		git checkout no_subtree_work_branch
+	) &&
+	test_create_commit "$subtree_test_count" not_a_subtree_change &&
+	(
+		cd "$subtree_test_count" &&
+		git checkout master &&
+		git merge -m "merge should be skipped on subtree" no_subtree_work_branch &&
+
+		git subtree split --prefix folder_subtree/ --branch subtree_tip master &&
+		git subtree split --prefix folder_subtree/ --branch subtree_branch branch &&
+		check_equal $(git rev-list --count subtree_tip..subtree_branch) 0
+	)
+'
+
+test_done