Add a test for rebase when a change was picked upstream

This test exercises the standard feature that makes rebase useful.

Signed-off-by: Yann Dirson <ydirson@altern.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

t/t3401-rebase-partial.sh

@@ -0,0 +1,53 @@
+#!/bin/sh
+#
+# Copyright (c) 2006 Yann Dirson, based on t3400 by Amos Waterland
+#
+
+test_description='git rebase should detect patches integrated upstream
+
+This test cherry-picks one local change of two into master branch, and
+checks that git rebase succeeds with only the second patch in the
+local branch.
+'
+. ./test-lib.sh
+
+test_expect_success \
+    'prepare repository with topic branch' \
+    'echo First > A &&
+     git-update-index --add A &&
+     git-commit -m "Add A." &&
+
+     git-checkout -b my-topic-branch &&
+
+     echo Second > B &&
+     git-update-index --add B &&
+     git-commit -m "Add B." &&
+
+     echo AnotherSecond > C &&
+     git-update-index --add C &&
+     git-commit -m "Add C." &&
+
+     git-checkout -f master &&
+
+     echo Third >> A &&
+     git-update-index A &&
+     git-commit -m "Modify A."
+'
+
+test_expect_success \
+    'pick top patch from topic branch into master' \
+    'git-cherry-pick my-topic-branch^0 &&
+     git-checkout -f my-topic-branch
+'
+
+test_debug \
+    'git-cherry master &&
+     git-format-patch -k --stdout --full-index master >/dev/null &&
+     gitk --all & sleep 1
+'
+
+test_expect_success \
+    'rebase topic branch against new master and check git-am did not get halted' \
+    'git-rebase master && test ! -d .dotest'
+
+test_done