#!/bin/sh
#
# Copyright (c) 2007 Lars Hjemli
#

test_description='git merge

Testing basic merge operations/option parsing.

! [c0] commit 0
 ! [c1] commit 1
  ! [c2] commit 2
   ! [c3] commit 3
    ! [c4] c4
     ! [c5] c5
      ! [c6] c6
       * [master] Merge commit 'c1'
--------
       - [master] Merge commit 'c1'
 +     * [c1] commit 1
      +  [c6] c6
     +   [c5] c5
    ++   [c4] c4
   ++++  [c3] commit 3
  +      [c2] commit 2
+++++++* [c0] commit 0
'

. ./test-lib.sh

test_expect_success 'set up test data and helpers' '
        printf "%s\n" 1 2 3 4 5 6 7 8 9 >file &&
        printf "%s\n" "1 X" 2 3 4 5 6 7 8 9 >file.1 &&
        printf "%s\n" 1 2 3 4 "5 X" 6 7 8 9 >file.5 &&
        printf "%s\n" 1 2 3 4 5 6 7 8 "9 X" >file.9 &&
        printf "%s\n" "1 X" 2 3 4 5 6 7 8 9 >result.1 &&
        printf "%s\n" "1 X" 2 3 4 "5 X" 6 7 8 9 >result.1-5 &&
        printf "%s\n" "1 X" 2 3 4 "5 X" 6 7 8 "9 X" >result.1-5-9 &&

        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:" &&
                        echo &&
                        git log --no-merges ^HEAD c1
                } >squash.1 &&
                {
                        echo "Squashed commit of the following:" &&
                        echo &&
                        git log --no-merges ^HEAD c2
                } >squash.1-5 &&
                {
                        echo "Squashed commit of the following:" &&
                        echo &&
                        git log --no-merges ^HEAD c2 c3
                } >squash.1-5-9 &&
                echo >msg.nolog &&
                {
                        echo "* commit '\''c3'\'':" &&
                        echo "  commit 3" &&
                        echo
                } >msg.log
        } &&

        verify_merge() {
                test_cmp "$2" "$1" &&
                git update-index --refresh &&
                git diff --exit-code &&
                if test -n "$3"
                then
                        git show -s --pretty=format:%s HEAD >msg.act &&
                        test_cmp "$3" msg.act
                fi
        } &&

        verify_head() {
                echo "$1" >head.expected &&
                git rev-parse HEAD >head.actual &&
                test_cmp head.expected head.actual
        } &&

        verify_parents() {
                printf "%s\n" "$@" >parents.expected &&
                >parents.actual &&
                i=1 &&
                while test $i -le $#
                do
                        git rev-parse HEAD^$i >>parents.actual &&
                        i=$(expr $i + 1) ||
                        return 1
                done &&
                test_cmp parents.expected parents.actual
        } &&

        verify_mergeheads() {
                printf "%s\n" "$@" >mergehead.expected &&
                test_cmp mergehead.expected .git/MERGE_HEAD
        } &&

        verify_no_mergehead() {
                ! test -e .git/MERGE_HEAD
        }
'

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 'git log --graph --decorate --oneline --all'

test_expect_success 'test option parsing' '
        test_must_fail git merge -$ c1 &&
        test_must_fail git merge --no-such c1 &&
        test_must_fail git merge -s foobar c1 &&
        test_must_fail git merge -s=foobar c1 &&
        test_must_fail git merge -m &&
        test_must_fail git merge
'

test_expect_success 'reject non-strategy with a git-merge-foo name' '
        test_must_fail git merge -s index c1
'

test_expect_success 'merge c0 with c1' '
        git reset --hard c0 &&
        git merge c1 &&
        verify_merge file result.1 &&
        verify_head "$c1"
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c0 with c1 with --ff-only' '
        git reset --hard c0 &&
        git merge --ff-only c1 &&
        git merge --ff-only HEAD c0 c1 &&
        verify_merge file result.1 &&
        verify_head "$c1"
'

test_debug 'git log --graph --decorate --oneline --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 'git log --graph --decorate --oneline --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 'git log --graph --decorate --oneline --all'

test_expect_success 'failing merges with --ff-only' '
        git reset --hard c1 &&
        test_tick &&
        test_must_fail git merge --ff-only c2 &&
        test_must_fail git merge --ff-only c3 &&
        test_must_fail git merge --ff-only c2 c3
'

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 'git log --graph --decorate --oneline --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 'git log --graph --decorate --oneline --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 'git log --graph --decorate --oneline --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 &&
        test_cmp squash.1 .git/SQUASH_MSG
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c0 with c1 (squash, ff-only)' '
        git reset --hard c0 &&
        git merge --squash --ff-only c1 &&
        verify_merge file result.1 &&
        verify_head $c0 &&
        verify_no_mergehead &&
        test_cmp squash.1 .git/SQUASH_MSG
'

test_debug 'git log --graph --decorate --oneline --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 &&
        test_cmp squash.1-5 .git/SQUASH_MSG
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'unsuccesful merge of c1 with c2 (squash, ff-only)' '
        git reset --hard c1 &&
        test_must_fail git merge --squash --ff-only c2
'

test_debug 'git log --graph --decorate --oneline --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 &&
        test_cmp squash.1-5-9 .git/SQUASH_MSG
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c2 (no-commit in config)' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "--no-commit" &&
        git merge c2 &&
        verify_merge file result.1-5 &&
        verify_head $c1 &&
        verify_mergeheads $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c2 (squash in config)' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "--squash" &&
        git merge c2 &&
        verify_merge file result.1-5 &&
        verify_head $c1 &&
        verify_no_mergehead &&
        test_cmp squash.1-5 .git/SQUASH_MSG
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'override config option -n with --summary' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "-n" &&
        test_tick &&
        git merge --summary c2 >diffstat.txt &&
        verify_merge file result.1-5 msg.1-5 &&
        verify_parents $c1 $c2 &&
        if ! grep "^ file |  *2 +-$" diffstat.txt
        then
                echo "[OOPS] diffstat was not generated with --summary"
                false
        fi
'

test_expect_success 'override config option -n with --stat' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "-n" &&
        test_tick &&
        git merge --stat c2 >diffstat.txt &&
        verify_merge file result.1-5 msg.1-5 &&
        verify_parents $c1 $c2 &&
        if ! grep "^ file |  *2 +-$" diffstat.txt
        then
                echo "[OOPS] diffstat was not generated with --stat"
                false
        fi
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'override config option --stat' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "--stat" &&
        test_tick &&
        git merge -n c2 >diffstat.txt &&
        verify_merge file result.1-5 msg.1-5 &&
        verify_parents $c1 $c2 &&
        if grep "^ file |  *2 +-$" diffstat.txt
        then
                echo "[OOPS] diffstat was generated"
                false
        fi
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c2 (override --no-commit)' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "--no-commit" &&
        test_tick &&
        git merge --commit c2 &&
        verify_merge file result.1-5 msg.1-5 &&
        verify_parents $c1 $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c2 (override --squash)' '
        git reset --hard c1 &&
        git config branch.master.mergeoptions "--squash" &&
        test_tick &&
        git merge --no-squash c2 &&
        verify_merge file result.1-5 msg.1-5 &&
        verify_parents $c1 $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c0 with c1 (no-ff)' '
        git reset --hard c0 &&
        git config branch.master.mergeoptions "" &&
        test_tick &&
        git merge --no-ff c1 &&
        verify_merge file result.1 &&
        verify_parents $c0 $c1
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'combining --squash and --no-ff is refused' '
        test_must_fail git merge --squash --no-ff c1 &&
        test_must_fail git merge --no-ff --squash c1
'

test_expect_success 'combining --ff-only and --no-ff is refused' '
        test_must_fail git merge --ff-only --no-ff c1 &&
        test_must_fail git merge --no-ff --ff-only c1
'

test_expect_success 'merge c0 with c1 (ff overrides no-ff)' '
        git reset --hard c0 &&
        git config branch.master.mergeoptions "--no-ff" &&
        git merge --ff c1 &&
        verify_merge file result.1 &&
        verify_head $c1
'

test_expect_success 'merge log message' '
        git reset --hard c0 &&
        git merge --no-log c2 &&
        git show -s --pretty=format:%b HEAD >msg.act &&
        test_cmp msg.nolog msg.act &&

        git merge --log c3 &&
        git show -s --pretty=format:%b HEAD >msg.act &&
        test_cmp msg.log msg.act &&

        git reset --hard HEAD^ &&
        git config merge.log yes &&
        git merge c3 &&
        git show -s --pretty=format:%b HEAD >msg.act &&
        test_cmp msg.log msg.act
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c0, c2, c0, and c1' '
       git reset --hard c1 &&
       git config branch.master.mergeoptions "" &&
       test_tick &&
       git merge c0 c2 c0 c1 &&
       verify_merge file result.1-5 &&
       verify_parents $c1 $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c0, c2, c0, and c1' '
       git reset --hard c1 &&
       git config branch.master.mergeoptions "" &&
       test_tick &&
       git merge c0 c2 c0 c1 &&
       verify_merge file result.1-5 &&
       verify_parents $c1 $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge c1 with c1 and c2' '
       git reset --hard c1 &&
       git config branch.master.mergeoptions "" &&
       test_tick &&
       git merge c1 c2 &&
       verify_merge file result.1-5 &&
       verify_parents $c1 $c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge fast-forward in a dirty tree' '
       git reset --hard c0 &&
       mv file file1 &&
       cat file1 >file &&
       rm -f file1 &&
       git merge c2
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'in-index merge' '
        git reset --hard c0 &&
        git merge --no-ff -s resolve c1 >out &&
        grep "Wonderful." out &&
        verify_parents $c0 $c1
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'refresh the index before merging' '
        git reset --hard c1 &&
        cp file file.n && mv -f file.n file &&
        git merge c3
'

cat >expected.branch <<\EOF
Merge branch 'c5-branch' (early part)
EOF
cat >expected.tag <<\EOF
Merge commit 'c5~1'
EOF

test_expect_success 'merge early part of c2' '
        git reset --hard c3 &&
        echo c4 >c4.c &&
        git add c4.c &&
        git commit -m c4 &&
        git tag c4 &&
        echo c5 >c5.c &&
        git add c5.c &&
        git commit -m c5 &&
        git tag c5 &&
        git reset --hard c3 &&
        echo c6 >c6.c &&
        git add c6.c &&
        git commit -m c6 &&
        git tag c6 &&
        git branch -f c5-branch c5 &&
        git merge c5-branch~1 &&
        git show -s --pretty=format:%s HEAD >actual.branch &&
        git reset --keep HEAD^ &&
        git merge c5~1 &&
        git show -s --pretty=format:%s HEAD >actual.tag &&
        test_cmp expected.branch actual.branch &&
        test_cmp expected.tag actual.tag
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'merge --no-ff --no-commit && commit' '
        git reset --hard c0 &&
        git merge --no-ff --no-commit c1 &&
        EDITOR=: git commit &&
        verify_parents $c0 $c1
'

test_debug 'git log --graph --decorate --oneline --all'

test_expect_success 'amending no-ff merge commit' '
        EDITOR=: git commit --amend &&
        verify_parents $c0 $c1
'

test_debug 'git log --graph --decorate --oneline --all'

test_done