#!/bin/sh

test_description='merging with submodules'

. ./test-lib.sh

#
# history
#
#        a --- c
#      /   \ /
# root      X
#      \   / \
#        b --- d
#

test_expect_success setup '

        mkdir sub &&
        (cd sub &&
         git init &&
         echo original > file &&
         git add file &&
         test_tick &&
         git commit -m sub-root) &&
        git add sub &&
        test_tick &&
        git commit -m root &&

        git checkout -b a master &&
        (cd sub &&
         echo A > file &&
         git add file &&
         test_tick &&
         git commit -m sub-a) &&
        git add sub &&
        test_tick &&
        git commit -m a &&

        git checkout -b b master &&
        (cd sub &&
         echo B > file &&
         git add file &&
         test_tick &&
         git commit -m sub-b) &&
        git add sub &&
        test_tick &&
        git commit -m b &&

        git checkout -b c a &&
        git merge -s ours b &&

        git checkout -b d b &&
        git merge -s ours a
'

# History setup
#
#             b
#           /   \
#  init -- a     d
#    \      \   /
#     g       c
#
# a in the main repository records to sub-a in the submodule and
# analogous b and c. d should be automatically found by merging c into
# b in the main repository.
test_expect_success 'setup for merge search' '
        mkdir merge-search &&
        (cd merge-search &&
        git init &&
        mkdir sub &&
        (cd sub &&
         git init &&
         echo "file-a" > file-a &&
         git add file-a &&
         git commit -m "sub-a" &&
         git branch sub-a) &&
        git commit --allow-empty -m init &&
        git branch init &&
        git add sub &&
        git commit -m "a" &&
        git branch a &&

        git checkout -b b &&
        (cd sub &&
         git checkout -b sub-b &&
         echo "file-b" > file-b &&
         git add file-b &&
         git commit -m "sub-b") &&
        git commit -a -m "b" &&

        git checkout -b c a &&
        (cd sub &&
         git checkout -b sub-c sub-a &&
         echo "file-c" > file-c &&
         git add file-c &&
         git commit -m "sub-c") &&
        git commit -a -m "c" &&

        git checkout -b d a &&
        (cd sub &&
         git checkout -b sub-d sub-b &&
         git merge sub-c) &&
        git commit -a -m "d" &&
        git branch test b &&

        git checkout -b g init &&
        (cd sub &&
         git checkout -b sub-g sub-c) &&
        git add sub &&
        git commit -a -m "g")
'

test_expect_success 'merge with one side as a fast-forward of the other' '
        (cd merge-search &&
         git checkout -b test-forward b &&
         git merge d &&
         git ls-tree test-forward sub | cut -f1 | cut -f3 -d" " > actual &&
         (cd sub &&
          git rev-parse sub-d > ../expect) &&
         test_cmp expect actual)
'

test_expect_success 'merging should conflict for non fast-forward' '
        (cd merge-search &&
         git checkout -b test-nonforward b &&
         (cd sub &&
          git rev-parse sub-d > ../expect) &&
         test_must_fail git merge c 2> actual  &&
         grep $(cat expect) actual > /dev/null &&
         git reset --hard)
'

test_expect_success 'merging should fail for ambiguous common parent' '
        (cd merge-search &&
        git checkout -b test-ambiguous b &&
        (cd sub &&
         git checkout -b ambiguous sub-b &&
         git merge sub-c &&
         git rev-parse sub-d > ../expect1 &&
         git rev-parse ambiguous > ../expect2) &&
        test_must_fail git merge c 2> actual &&
        grep $(cat expect1) actual > /dev/null &&
        grep $(cat expect2) actual > /dev/null &&
        git reset --hard)
'

# in a situation like this
#
# submodule tree:
#
#    sub-a --- sub-b --- sub-d
#
# main tree:
#
#    e (sub-a)
#   /
#  bb (sub-b)
#   \
#    f (sub-d)
#
# A merge between e and f should fail because one of the submodule
# commits (sub-a) does not descend from the submodule merge-base (sub-b).
#
test_expect_success 'merging should fail for changes that are backwards' '
        (cd merge-search &&
        git checkout -b bb a &&
        (cd sub &&
         git checkout sub-b) &&
        git commit -a -m "bb" &&

        git checkout -b e bb &&
        (cd sub &&
         git checkout sub-a) &&
        git commit -a -m "e" &&

        git checkout -b f bb &&
        (cd sub &&
         git checkout sub-d) &&
        git commit -a -m "f" &&

        git checkout -b test-backward e &&
        test_must_fail git merge f)
'


# Check that the conflicting submodule is detected when it is
# in the common ancestor. status should be 'U00...00"
test_expect_success 'git submodule status should display the merge conflict properly with merge base' '
       (cd merge-search &&
       cat >.gitmodules <<EOF &&
[submodule "sub"]
       path = sub
       url = $TRASH_DIRECTORY/sub
EOF
       cat >expect <<EOF &&
U0000000000000000000000000000000000000000 sub
EOF
       git submodule status > actual &&
       test_cmp expect actual &&
        git reset --hard)
'

# Check that the conflicting submodule is detected when it is
# not in the common ancestor. status should be 'U00...00"
test_expect_success 'git submodule status should display the merge conflict properly without merge-base' '
       (cd merge-search &&
        git checkout -b test-no-merge-base g &&
        test_must_fail git merge b &&
       cat >.gitmodules <<EOF &&
[submodule "sub"]
       path = sub
       url = $TRASH_DIRECTORY/sub
EOF
       cat >expect <<EOF &&
U0000000000000000000000000000000000000000 sub
EOF
       git submodule status > actual &&
       test_cmp expect actual &&
       git reset --hard)
'


test_expect_success 'merging with a modify/modify conflict between merge bases' '
        git reset --hard HEAD &&
        git checkout -b test2 c &&
        git merge d
'

# canonical criss-cross history in top and submodule
test_expect_success 'setup for recursive merge with submodule' '
        mkdir merge-recursive &&
        (cd merge-recursive &&
         git init &&
         mkdir sub &&
         (cd sub &&
          git init &&
          test_commit a &&
          git checkout -b sub-b master &&
          test_commit b &&
          git checkout -b sub-c master &&
          test_commit c &&
          git checkout -b sub-bc sub-b &&
          git merge sub-c &&
          git checkout -b sub-cb sub-c &&
          git merge sub-b &&
          git checkout master) &&
         git add sub &&
         git commit -m a &&
         git checkout -b top-b master &&
         (cd sub && git checkout sub-b) &&
         git add sub &&
         git commit -m b &&
         git checkout -b top-c master &&
         (cd sub && git checkout sub-c) &&
         git add sub &&
         git commit -m c &&
         git checkout -b top-bc top-b &&
         git merge -s ours --no-commit top-c &&
         (cd sub && git checkout sub-bc) &&
         git add sub &&
         git commit -m bc &&
         git checkout -b top-cb top-c &&
         git merge -s ours --no-commit top-b &&
         (cd sub && git checkout sub-cb) &&
         git add sub &&
         git commit -m cb)
'

# merge should leave submodule unmerged in index
test_expect_success 'recursive merge with submodule' '
        (cd merge-recursive &&
         test_must_fail git merge top-bc &&
         echo "160000 $(git rev-parse top-cb:sub) 2     sub" > expect2 &&
         echo "160000 $(git rev-parse top-bc:sub) 3     sub" > expect3 &&
         git ls-files -u > actual &&
         grep "$(cat expect2)" actual > /dev/null &&
         grep "$(cat expect3)" actual > /dev/null)
'

# File/submodule conflict
#   Commit O: <empty>
#   Commit A: path (submodule)
#   Commit B: path
#   Expected: path/ is submodule and file contents for B's path are somewhere

test_expect_success 'setup file/submodule conflict' '
        test_create_repo file-submodule &&
        (
                cd file-submodule &&

                git commit --allow-empty -m O &&

                git branch A &&
                git branch B &&

                git checkout B &&
                echo content >path &&
                git add path &&
                git commit -m B &&

                git checkout A &&
                test_create_repo path &&
                test_commit -C path world &&
                git submodule add ./path &&
                git commit -m A
        )
'

test_expect_failure 'file/submodule conflict' '
        test_when_finished "git -C file-submodule reset --hard" &&
        (
                cd file-submodule &&

                git checkout A^0 &&
                test_must_fail git merge B^0 &&

                git ls-files -s >out &&
                test_line_count = 3 out &&
                git ls-files -u >out &&
                test_line_count = 2 out &&

                # path/ is still a submodule
                test_path_is_dir path/.git &&

                # There is a submodule at "path", so B:path cannot be written
                # there.  We expect it to be written somewhere in the same
                # directory, though, so just grep for its content in all
                # files, and ignore "grep: path: Is a directory" message
                echo Checking if contents from B:path showed up anywhere &&
                grep -q content * 2>/dev/null
        )
'

test_expect_success 'file/submodule conflict; merge --abort works afterward' '
        test_when_finished "git -C file-submodule reset --hard" &&
        (
                cd file-submodule &&

                git checkout A^0 &&
                test_must_fail git merge B^0 >out 2>err &&

                test_path_is_file .git/MERGE_HEAD &&
                git merge --abort
        )
'

# Directory/submodule conflict
#   Commit O: <empty>
#   Commit A: path (submodule), with sole tracked file named 'world'
#   Commit B1: path/file
#   Commit B2: path/world
#
#   Expected from merge of A & B1:
#     Contents under path/ from commit B1 are renamed elsewhere; we do not
#     want to write files from one of our tracked directories into a submodule
#
#   Expected from merge of A & B2:
#     Similar to last merge, but with a slight twist: we don't want paths
#     under the submodule to be treated as untracked or in the way.

test_expect_success 'setup directory/submodule conflict' '
        test_create_repo directory-submodule &&
        (
                cd directory-submodule &&

                git commit --allow-empty -m O &&

                git branch A &&
                git branch B1 &&
                git branch B2 &&

                git checkout B1 &&
                mkdir path &&
                echo contents >path/file &&
                git add path/file &&
                git commit -m B1 &&

                git checkout B2 &&
                mkdir path &&
                echo contents >path/world &&
                git add path/world &&
                git commit -m B2 &&

                git checkout A &&
                test_create_repo path &&
                test_commit -C path hello world &&
                git submodule add ./path &&
                git commit -m A
        )
'

test_expect_failure 'directory/submodule conflict; keep submodule clean' '
        test_when_finished "git -C directory-submodule reset --hard" &&
        (
                cd directory-submodule &&

                git checkout A^0 &&
                test_must_fail git merge B1^0 &&

                git ls-files -s >out &&
                test_line_count = 3 out &&
                git ls-files -u >out &&
                test_line_count = 1 out &&

                # path/ is still a submodule
                test_path_is_dir path/.git &&

                echo Checking if contents from B1:path/file showed up &&
                # Would rather use grep -r, but that is GNU extension...
                git ls-files -co | xargs grep -q contents 2>/dev/null &&

                # However, B1:path/file should NOT have shown up at path/file,
                # because we should not write into the submodule
                test_path_is_missing path/file
        )
'

test_expect_failure !FAIL_PREREQS 'directory/submodule conflict; should not treat submodule files as untracked or in the way' '
        test_when_finished "git -C directory-submodule/path reset --hard" &&
        test_when_finished "git -C directory-submodule reset --hard" &&
        (
                cd directory-submodule &&

                git checkout A^0 &&
                test_must_fail git merge B2^0 >out 2>err &&

                # We do not want files within the submodule to prevent the
                # merge from starting; we should not be writing to such paths
                # anyway.
                test_i18ngrep ! "refusing to lose untracked file at" err
        )
'

test_expect_failure 'directory/submodule conflict; merge --abort works afterward' '
        test_when_finished "git -C directory-submodule/path reset --hard" &&
        test_when_finished "git -C directory-submodule reset --hard" &&
        (
                cd directory-submodule &&

                git checkout A^0 &&
                test_must_fail git merge B2^0 &&
                test_path_is_file .git/MERGE_HEAD &&

                # merge --abort should succeed, should clear .git/MERGE_HEAD,
                # and should not leave behind any conflicted files
                git merge --abort &&
                test_path_is_missing .git/MERGE_HEAD &&
                git ls-files -u >conflicts &&
                test_must_be_empty conflicts
        )
'

test_done