Add test-script for git-merge porcelain

This test-script excercises the porcelainish aspects of git-merge, and
does it thoroughly enough to detect a small bug already noticed by Junio:
squashing an octopus generates a faulty .git/SQUASH_MSG.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t7600-merge.sh b/t/t7600-merge.sh
new file mode 100755 (executable)
index 0000000..dec6ea2
--- /dev/null
+++ b/t/t7600-merge.sh
@@ -0,0 +1,344 @@
+#!/bin/sh
+#
+# Copyright (c) 2007 Lars Hjemli
+#
+
+test_description='git-merge
+
+Testing basic merge operations/option parsing.'
+
+. ./test-lib.sh
+
+cat >file <<EOF
+1
+2
+3
+4
+5
+6
+7
+8
+9
+EOF
+
+cat >file.1 <<EOF
+1 X
+2
+3
+4
+5
+6
+7
+8
+9
+EOF
+
+cat >file.5 <<EOF
+1
+2
+3
+4
+5 X
+6
+7
+8
+9
+EOF
+
+cat >file.9 <<EOF
+1
+2
+3
+4
+5
+6
+7
+8
+9 X
+EOF
+
+cat  >result.1 <<EOF
+1 X
+2
+3
+4
+5
+6
+7
+8
+9
+EOF
+
+cat >result.1-5 <<EOF
+1 X
+2
+3
+4
+5 X
+6
+7
+8
+9
+EOF
+
+cat >result.1-5-9 <<EOF
+1 X
+2
+3
+4
+5 X
+6
+7
+8
+9 X
+EOF
+
+create_merge_msgs() {
+       echo "Merge commit 'c2'" >msg.1-5 &&
+       echo "Merge commit 'c2'; commit 'c3'" >msg.1-5-9 &&
+       echo "Squashed commit of the following:" >squash.1 &&
+       echo >>squash.1 &&
+       git log --no-merges ^HEAD c1 >>squash.1 &&
+       echo "Squashed commit of the following:" >squash.1-5 &&
+       echo >>squash.1-5 &&
+       git log --no-merges ^HEAD c2 >>squash.1-5 &&
+       echo "Squashed commit of the following:" >squash.1-5-9 &&
+       echo >>squash.1-5-9 &&
+       git log --no-merges ^HEAD c2 c3 >>squash.1-5-9
+}
+
+verify_diff() {
+       if ! diff -u "$1" "$2"
+       then
+               echo "$3"
+               false
+       fi
+}
+
+verify_merge() {
+       verify_diff "$2" "$1" "[OOPS] bad merge result" &&
+       if test $(git ls-files -u | wc -l) -gt 0
+       then
+               echo "[OOPS] unmerged files"
+               false
+       fi &&
+       if ! git diff --exit-code
+       then
+               echo "[OOPS] working tree != index"
+               false
+       fi &&
+       if test -n "$3"
+       then
+               git show -s --pretty=format:%s HEAD >msg.act &&
+               verify_diff "$3" msg.act "[OOPS] bad merge message"
+       fi
+}
+
+verify_head() {
+       if test "$1" != "$(git rev-parse HEAD)"
+       then
+               echo "[OOPS] HEAD != $1"
+               false
+       fi
+}
+
+verify_parents() {
+       i=1
+       while test $# -gt 0
+       do
+               if test "$1" != "$(git rev-parse HEAD^$i)"
+               then
+                       echo "[OOPS] HEAD^$i != $1"
+                       return 1
+               fi
+               i=$(expr $i + 1)
+               shift
+       done
+}
+
+verify_mergeheads() {
+       i=1
+       if ! test -f .git/MERGE_HEAD
+       then
+               echo "[OOPS] MERGE_HEAD is missing"
+               false
+       fi &&
+       while test $# -gt 0
+       do
+               head=$(head -n $i .git/MERGE_HEAD | tail -n 1)
+               if test "$1" != "$head"
+               then
+                       echo "[OOPS] MERGE_HEAD $i != $1"
+                       return 1
+               fi
+               i=$(expr $i + 1)
+               shift
+       done
+}
+
+verify_no_mergehead() {
+       if test -f .git/MERGE_HEAD
+       then
+               echo "[OOPS] MERGE_HEAD exists"
+               false
+       fi
+}
+
+
+test_expect_success 'setup' '
+       git add file &&
+       test_tick &&
+       git commit -m "commit 0" &&
+       git tag c0 &&
+       c0=$(git rev-parse HEAD) &&
+       cp file.1 file &&
+       git add file &&
+       test_tick &&
+       git commit -m "commit 1" &&
+       git tag c1 &&
+       c1=$(git rev-parse HEAD) &&
+       git reset --hard "$c0" &&
+       cp file.5 file &&
+       git add file &&
+       test_tick &&
+       git commit -m "commit 2" &&
+       git tag c2 &&
+       c2=$(git rev-parse HEAD) &&
+       git reset --hard "$c0" &&
+       cp file.9 file &&
+       git add file &&
+       test_tick &&
+       git commit -m "commit 3" &&
+       git tag c3 &&
+       c3=$(git rev-parse HEAD)
+       git reset --hard "$c0" &&
+       create_merge_msgs
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'test option parsing' '
+       if git merge -$ c1
+       then
+               echo "[OOPS] -$ accepted"
+               false
+       fi &&
+       if git merge --no-such c1
+       then
+               echo "[OOPS] --no-such accepted"
+               false
+       fi &&
+       if git merge -s foobar c1
+       then
+               echo "[OOPS] -s foobar accepted"
+               false
+       fi &&
+       if git merge -s=foobar c1
+       then
+               echo "[OOPS] -s=foobar accepted"
+               false
+       fi &&
+       if git merge -m
+       then
+               echo "[OOPS] missing commit msg accepted"
+               false
+       fi &&
+       if git merge
+       then
+               echo "[OOPS] missing commit references accepted"
+               false
+       fi
+'
+
+test_expect_success 'merge c0 with c1' '
+       git reset --hard c0 &&
+       git merge c1 &&
+       verify_merge file result.1 &&
+       verify_head "$c1"
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2' '
+       git reset --hard c1 &&
+       test_tick &&
+       git merge c2 &&
+       verify_merge file result.1-5 msg.1-5 &&
+       verify_parents $c1 $c2
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2 and c3' '
+       git reset --hard c1 &&
+       test_tick &&
+       git merge c2 c3 &&
+       verify_merge file result.1-5-9 msg.1-5-9 &&
+       verify_parents $c1 $c2 $c3
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c0 with c1 (no-commit)' '
+       git reset --hard c0 &&
+       git merge --no-commit c1 &&
+       verify_merge file result.1 &&
+       verify_head $c1
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2 (no-commit)' '
+       git reset --hard c1 &&
+       git merge --no-commit c2 &&
+       verify_merge file result.1-5 &&
+       verify_head $c1 &&
+       verify_mergeheads $c2
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2 and c3 (no-commit)' '
+       git reset --hard c1 &&
+       git merge --no-commit c2 c3 &&
+       verify_merge file result.1-5-9 &&
+       verify_head $c1 &&
+       verify_mergeheads $c2 $c3
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c0 with c1 (squash)' '
+       git reset --hard c0 &&
+       git merge --squash c1 &&
+       verify_merge file result.1 &&
+       verify_head $c0 &&
+       verify_no_mergehead &&
+       verify_diff squash.1 .git/SQUASH_MSG "[OOPS] bad squash message"
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2 (squash)' '
+       git reset --hard c1 &&
+       git merge --squash c2 &&
+       verify_merge file result.1-5 &&
+       verify_head $c1 &&
+       verify_no_mergehead &&
+       verify_diff squash.1-5 .git/SQUASH_MSG "[OOPS] bad squash message"
+'
+
+test_debug 'gitk --all'
+
+test_expect_success 'merge c1 with c2 and c3 (squash)' '
+       git reset --hard c1 &&
+       git merge --squash c2 c3 &&
+       verify_merge file result.1-5-9 &&
+       verify_head $c1 &&
+       verify_no_mergehead &&
+       verify_diff squash.1-5-9 .git/SQUASH_MSG "[OOPS] bad squash message"
+'
+
+test_debug 'gitk --all'
+
+test_done