Add a demonstration/test of customized merge.

This demonstrates how the new low-level per-path merge backends,
union and ours, work, and shows how they are controlled by the
gitattribute mechanism.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/t/t6026-merge-attr.sh b/t/t6026-merge-attr.sh
new file mode 100755 (executable)
index 0000000..5daa223
--- /dev/null
+++ b/t/t6026-merge-attr.sh
@@ -0,0 +1,72 @@
+#!/bin/sh
+#
+# Copyright (c) 2007 Junio C Hamano
+#
+
+test_description='per path merge controlled by merge attribute'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+
+       for f in text binary union
+       do
+               echo Initial >$f && git add $f || break
+       done &&
+       test_tick &&
+       git commit -m Initial &&
+
+       git branch side &&
+       for f in text binary union
+       do
+               echo Master >>$f && git add $f || break
+       done &&
+       test_tick &&
+       git commit -m Master &&
+
+       git checkout side &&
+       for f in text binary union
+       do
+               echo Side >>$f && git add $f || break
+       done &&
+       test_tick &&
+       git commit -m Side
+
+'
+
+test_expect_success merge '
+
+       {
+               echo "binary -merge"
+               echo "union merge=union"
+       } >.gitattributes &&
+
+       if git merge master
+       then
+               echo Gaah, should have conflicted
+               false
+       else
+               echo Ok, conflicted.
+       fi
+'
+
+test_expect_success 'check merge result in index' '
+
+       git ls-files -u | grep binary &&
+       git ls-files -u | grep text &&
+       ! (git ls-files -u | grep union)
+
+'
+
+test_expect_success 'check merge result in working tree' '
+
+       git cat-file -p HEAD:binary >binary-orig &&
+       grep "<<<<<<<" text &&
+       cmp binary-orig binary &&
+       ! grep "<<<<<<<" union &&
+       grep Master union &&
+       grep Side union
+
+'
+
+test_done