From 9db5ebf4022d8e11ac20e75a3d43af161b752fcd Mon Sep 17 00:00:00 2001
From: Erick Mattos <erick.mattos@gmail.com>
Date: Sun, 21 Mar 2010 12:34:38 -0300
Subject: git checkout: create unparented branch by --orphan

Similar to -b, --orphan creates a new branch, but it starts without any
commit.  After running "git checkout --orphan newbranch", you are on a
new branch "newbranch", and the first commit you create from this state
will start a new history without any ancestry.

"git checkout --orphan" keeps the index and the working tree files
intact in order to make it convenient for creating a new history whose
trees resemble the ones from the original branch.

When creating a branch whose trees have no resemblance to the ones from
the original branch, it may be easier to start work on the new branch by
untracking and removing all working tree files that came from the
original branch, by running a 'git rm -rf .' immediately after running
"checkout --orphan".

Signed-off-by: Erick Mattos <erick.mattos@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 t/t2017-checkout-orphan.sh | 90 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100755 t/t2017-checkout-orphan.sh

(limited to 't')

diff --git a/t/t2017-checkout-orphan.sh b/t/t2017-checkout-orphan.sh
new file mode 100755
index 0000000000..a8297c61bd
--- /dev/null
+++ b/t/t2017-checkout-orphan.sh
@@ -0,0 +1,90 @@
+#!/bin/sh
+#
+# Copyright (c) 2010 Erick Mattos
+#
+
+test_description='git checkout --orphan
+
+Main Tests for --orphan functionality.'
+
+. ./test-lib.sh
+
+TEST_FILE=foo
+
+test_expect_success 'Setup' '
+	echo "Initial" >"$TEST_FILE" &&
+	git add "$TEST_FILE" &&
+	git commit -m "First Commit"
+	test_tick &&
+	echo "State 1" >>"$TEST_FILE" &&
+	git add "$TEST_FILE" &&
+	test_tick &&
+	git commit -m "Second Commit"
+'
+
+test_expect_success '--orphan creates a new orphan branch from HEAD' '
+	git checkout --orphan alpha &&
+	test_must_fail git rev-parse --verify HEAD &&
+	test "refs/heads/alpha" = "$(git symbolic-ref HEAD)" &&
+	test_tick &&
+	git commit -m "Third Commit" &&
+	test_must_fail git rev-parse --verify HEAD^ &&
+	git diff-tree --quiet master alpha
+'
+
+test_expect_success '--orphan creates a new orphan branch from <start_point>' '
+	git checkout master &&
+	git checkout --orphan beta master^ &&
+	test_must_fail git rev-parse --verify HEAD &&
+	test "refs/heads/beta" = "$(git symbolic-ref HEAD)" &&
+	test_tick &&
+	git commit -m "Fourth Commit" &&
+	test_must_fail git rev-parse --verify HEAD^ &&
+	git diff-tree --quiet master^ beta
+'
+
+test_expect_success '--orphan must be rejected with -b' '
+	git checkout master &&
+	test_must_fail git checkout --orphan new -b newer &&
+	test refs/heads/master = "$(git symbolic-ref HEAD)"
+'
+
+test_expect_success '--orphan is rejected with an existing name' '
+	git checkout master &&
+	test_must_fail git checkout --orphan master &&
+	test refs/heads/master = "$(git symbolic-ref HEAD)"
+'
+
+test_expect_success '--orphan refuses to switch if a merge is needed' '
+	git checkout master &&
+	git reset --hard &&
+	echo local >>"$TEST_FILE" &&
+	cat "$TEST_FILE" >"$TEST_FILE.saved" &&
+	test_must_fail git checkout --orphan gamma master^ &&
+	test refs/heads/master = "$(git symbolic-ref HEAD)" &&
+	test_cmp "$TEST_FILE" "$TEST_FILE.saved" &&
+	git diff-index --quiet --cached HEAD &&
+	git reset --hard
+'
+
+test_expect_success '--orphan does not mix well with -t' '
+	git checkout master &&
+	test_must_fail git checkout -t master --orphan gamma &&
+	test refs/heads/master = "$(git symbolic-ref HEAD)"
+'
+
+test_expect_success '--orphan ignores branch.autosetupmerge' '
+	git checkout -f master &&
+	git config branch.autosetupmerge always &&
+	git checkout --orphan delta &&
+	test -z "$(git config branch.delta.merge)" &&
+	test refs/heads/delta = "$(git symbolic-ref HEAD)" &&
+	test_must_fail git rev-parse --verify HEAD^
+'
+
+test_expect_success '--orphan does not mix well with -l' '
+	git checkout -f master &&
+	test_must_fail git checkout -l --orphan gamma
+'
+
+test_done
-- 
cgit v1.2.3