#!/bin/sh
#
# Copyright (c) 2007 Christian Couder
#
test_description='Tests git bisect functionality'

exec </dev/null

. ./test-lib.sh

add_line_into_file()
{
    _line=$1
    _file=$2

    if [ -f "$_file" ]; then
        echo "$_line" >> $_file || return $?
        MSG="Add <$_line> into <$_file>."
    else
        echo "$_line" > $_file || return $?
        git add $_file || return $?
        MSG="Create file <$_file> with <$_line> inside."
    fi

    test_tick
    git commit --quiet -m "$MSG" $_file
}

HASH1=
HASH2=
HASH3=
HASH4=

test_expect_success 'set up basic repo with 1 file (hello) and 4 commits' '
     add_line_into_file "1: Hello World" hello &&
     HASH1=$(git rev-parse --verify HEAD) &&
     add_line_into_file "2: A new day for git" hello &&
     HASH2=$(git rev-parse --verify HEAD) &&
     add_line_into_file "3: Another new day for git" hello &&
     HASH3=$(git rev-parse --verify HEAD) &&
     add_line_into_file "4: Ciao for now" hello &&
     HASH4=$(git rev-parse --verify HEAD)
'

test_expect_success 'bisect starts with only one bad' '
        git bisect reset &&
        git bisect start &&
        git bisect bad $HASH4 &&
        git bisect next
'

test_expect_success 'bisect does not start with only one good' '
        git bisect reset &&
        git bisect start &&
        git bisect good $HASH1 || return 1

        if git bisect next
        then
                echo Oops, should have failed.
                false
        else
                :
        fi
'

test_expect_success 'bisect start with one bad and good' '
        git bisect reset &&
        git bisect start &&
        git bisect good $HASH1 &&
        git bisect bad $HASH4 &&
        git bisect next
'

test_expect_success 'bisect fails if given any junk instead of revs' '
        git bisect reset &&
        test_must_fail git bisect start foo $HASH1 -- &&
        test_must_fail git bisect start $HASH4 $HASH1 bar -- &&
        test -z "$(git for-each-ref "refs/bisect/*")" &&
        test -z "$(ls .git/BISECT_* 2>/dev/null)" &&
        git bisect start &&
        test_must_fail git bisect good foo $HASH1 &&
        test_must_fail git bisect good $HASH1 bar &&
        test_must_fail git bisect bad frotz &&
        test_must_fail git bisect bad $HASH3 $HASH4 &&
        test_must_fail git bisect skip bar $HASH3 &&
        test_must_fail git bisect skip $HASH1 foo &&
        test -z "$(git for-each-ref "refs/bisect/*")" &&
        git bisect good $HASH1 &&
        git bisect bad $HASH4
'

test_expect_success 'bisect reset: back in the master branch' '
        git bisect reset &&
        echo "* master" > branch.expect &&
        git branch > branch.output &&
        cmp branch.expect branch.output
'

test_expect_success 'bisect reset: back in another branch' '
        git checkout -b other &&
        git bisect start &&
        git bisect good $HASH1 &&
        git bisect bad $HASH3 &&
        git bisect reset &&
        echo "  master" > branch.expect &&
        echo "* other" >> branch.expect &&
        git branch > branch.output &&
        cmp branch.expect branch.output
'

test_expect_success 'bisect reset when not bisecting' '
        git bisect reset &&
        git branch > branch.output &&
        cmp branch.expect branch.output
'

test_expect_success 'bisect reset removes packed refs' '
        git bisect reset &&
        git bisect start &&
        git bisect good $HASH1 &&
        git bisect bad $HASH3 &&
        git pack-refs --all --prune &&
        git bisect next &&
        git bisect reset &&
        test -z "$(git for-each-ref "refs/bisect/*")" &&
        test -z "$(git for-each-ref "refs/heads/bisect")"
'

test_expect_success 'bisect start: back in good branch' '
        git branch > branch.output &&
        grep "* other" branch.output > /dev/null &&
        git bisect start $HASH4 $HASH1 -- &&
        git bisect good &&
        git bisect start $HASH4 $HASH1 -- &&
        git bisect bad &&
        git bisect reset &&
        git branch > branch.output &&
        grep "* other" branch.output > /dev/null
'

test_expect_success 'bisect start: no ".git/BISECT_START" if junk rev' '
        git bisect start $HASH4 $HASH1 -- &&
        git bisect good &&
        test_must_fail git bisect start $HASH4 foo -- &&
        git branch > branch.output &&
        grep "* other" branch.output > /dev/null &&
        test_must_fail test -e .git/BISECT_START
'

test_expect_success 'bisect start: no ".git/BISECT_START" if mistaken rev' '
        git bisect start $HASH4 $HASH1 -- &&
        git bisect good &&
        test_must_fail git bisect start $HASH1 $HASH4 -- &&
        git branch > branch.output &&
        grep "* other" branch.output > /dev/null &&
        test_must_fail test -e .git/BISECT_START
'

test_expect_success 'bisect start: no ".git/BISECT_START" if checkout error' '
        echo "temp stuff" > hello &&
        test_must_fail git bisect start $HASH4 $HASH1 -- &&
        git branch &&
        git branch > branch.output &&
        grep "* other" branch.output > /dev/null &&
        test_must_fail test -e .git/BISECT_START &&
        test -z "$(git for-each-ref "refs/bisect/*")" &&
        git checkout HEAD hello
'

# $HASH1 is good, $HASH4 is bad, we skip $HASH3
# but $HASH2 is bad,
# so we should find $HASH2 as the first bad commit
test_expect_success 'bisect skip: successfull result' '
        git bisect reset &&
        git bisect start $HASH4 $HASH1 &&
        git bisect skip &&
        git bisect bad > my_bisect_log.txt &&
        grep "$HASH2 is first bad commit" my_bisect_log.txt &&
        git bisect reset
'

# $HASH1 is good, $HASH4 is bad, we skip $HASH3 and $HASH2
# so we should not be able to tell the first bad commit
# among $HASH2, $HASH3 and $HASH4
test_expect_success 'bisect skip: cannot tell between 3 commits' '
        git bisect start $HASH4 $HASH1 &&
        git bisect skip || return 1

        if git bisect skip > my_bisect_log.txt
        then
                echo Oops, should have failed.
                false
        else
                test $? -eq 2 &&
                grep "first bad commit could be any of" my_bisect_log.txt &&
                ! grep $HASH1 my_bisect_log.txt &&
                grep $HASH2 my_bisect_log.txt &&
                grep $HASH3 my_bisect_log.txt &&
                grep $HASH4 my_bisect_log.txt &&
                git bisect reset
        fi
'

# $HASH1 is good, $HASH4 is bad, we skip $HASH3
# but $HASH2 is good,
# so we should not be able to tell the first bad commit
# among $HASH3 and $HASH4
test_expect_success 'bisect skip: cannot tell between 2 commits' '
        git bisect start $HASH4 $HASH1 &&
        git bisect skip || return 1

        if git bisect good > my_bisect_log.txt
        then
                echo Oops, should have failed.
                false
        else
                test $? -eq 2 &&
                grep "first bad commit could be any of" my_bisect_log.txt &&
                ! grep $HASH1 my_bisect_log.txt &&
                ! grep $HASH2 my_bisect_log.txt &&
                grep $HASH3 my_bisect_log.txt &&
                grep $HASH4 my_bisect_log.txt &&
                git bisect reset
        fi
'

# We want to automatically find the commit that
# introduced "Another" into hello.
test_expect_success \
    '"git bisect run" simple case' \
    'echo "#"\!"/bin/sh" > test_script.sh &&
     echo "grep Another hello > /dev/null" >> test_script.sh &&
     echo "test \$? -ne 0" >> test_script.sh &&
     chmod +x test_script.sh &&
     git bisect start &&
     git bisect good $HASH1 &&
     git bisect bad $HASH4 &&
     git bisect run ./test_script.sh > my_bisect_log.txt &&
     grep "$HASH3 is first bad commit" my_bisect_log.txt &&
     git bisect reset'

# We want to automatically find the commit that
# introduced "Ciao" into hello.
test_expect_success \
    '"git bisect run" with more complex "git bisect start"' \
    'echo "#"\!"/bin/sh" > test_script.sh &&
     echo "grep Ciao hello > /dev/null" >> test_script.sh &&
     echo "test \$? -ne 0" >> test_script.sh &&
     chmod +x test_script.sh &&
     git bisect start $HASH4 $HASH1 &&
     git bisect run ./test_script.sh > my_bisect_log.txt &&
     grep "$HASH4 is first bad commit" my_bisect_log.txt &&
     git bisect reset'

# $HASH1 is good, $HASH5 is bad, we skip $HASH3
# but $HASH4 is good,
# so we should find $HASH5 as the first bad commit
HASH5=
test_expect_success 'bisect skip: add line and then a new test' '
        add_line_into_file "5: Another new line." hello &&
        HASH5=$(git rev-parse --verify HEAD) &&
        git bisect start $HASH5 $HASH1 &&
        git bisect skip &&
        git bisect good > my_bisect_log.txt &&
        grep "$HASH5 is first bad commit" my_bisect_log.txt &&
        git bisect log > log_to_replay.txt &&
        git bisect reset
'

test_expect_success 'bisect skip and bisect replay' '
        git bisect replay log_to_replay.txt > my_bisect_log.txt &&
        grep "$HASH5 is first bad commit" my_bisect_log.txt &&
        git bisect reset
'

HASH6=
test_expect_success 'bisect run & skip: cannot tell between 2' '
        add_line_into_file "6: Yet a line." hello &&
        HASH6=$(git rev-parse --verify HEAD) &&
        echo "#"\!"/bin/sh" > test_script.sh &&
        echo "sed -ne \\\$p hello | grep Ciao > /dev/null && exit 125" >> test_script.sh &&
        echo "grep line hello > /dev/null" >> test_script.sh &&
        echo "test \$? -ne 0" >> test_script.sh &&
        chmod +x test_script.sh &&
        git bisect start $HASH6 $HASH1 &&
        if git bisect run ./test_script.sh > my_bisect_log.txt
        then
                echo Oops, should have failed.
                false
        else
                test $? -eq 2 &&
                grep "first bad commit could be any of" my_bisect_log.txt &&
                ! grep $HASH3 my_bisect_log.txt &&
                ! grep $HASH6 my_bisect_log.txt &&
                grep $HASH4 my_bisect_log.txt &&
                grep $HASH5 my_bisect_log.txt
        fi
'

HASH7=
test_expect_success 'bisect run & skip: find first bad' '
        git bisect reset &&
        add_line_into_file "7: Should be the last line." hello &&
        HASH7=$(git rev-parse --verify HEAD) &&
        echo "#"\!"/bin/sh" > test_script.sh &&
        echo "sed -ne \\\$p hello | grep Ciao > /dev/null && exit 125" >> test_script.sh &&
        echo "sed -ne \\\$p hello | grep day > /dev/null && exit 125" >> test_script.sh &&
        echo "grep Yet hello > /dev/null" >> test_script.sh &&
        echo "test \$? -ne 0" >> test_script.sh &&
        chmod +x test_script.sh &&
        git bisect start $HASH7 $HASH1 &&
        git bisect run ./test_script.sh > my_bisect_log.txt &&
        grep "$HASH6 is first bad commit" my_bisect_log.txt
'

test_expect_success 'bisect starting with a detached HEAD' '

        git bisect reset &&
        git checkout master^ &&
        HEAD=$(git rev-parse --verify HEAD) &&
        git bisect start &&
        test $HEAD = $(cat .git/BISECT_START) &&
        git bisect reset &&
        test $HEAD = $(git rev-parse --verify HEAD)
'

test_expect_success 'bisect errors out if bad and good are mistaken' '
        git bisect reset &&
        test_must_fail git bisect start $HASH2 $HASH4 2> rev_list_error &&
        grep "mistake good and bad" rev_list_error &&
        git bisect reset
'

test_expect_success 'bisect does not create a "bisect" branch' '
        git bisect reset &&
        git bisect start $HASH7 $HASH1 &&
        git branch bisect &&
        rev_hash4=$(git rev-parse --verify HEAD) &&
        test "$rev_hash4" = "$HASH4" &&
        git branch -D bisect &&
        git bisect good &&
        git branch bisect &&
        rev_hash6=$(git rev-parse --verify HEAD) &&
        test "$rev_hash6" = "$HASH6" &&
        git bisect good > my_bisect_log.txt &&
        grep "$HASH7 is first bad commit" my_bisect_log.txt &&
        git bisect reset &&
        rev_hash6=$(git rev-parse --verify bisect) &&
        test "$rev_hash6" = "$HASH6" &&
        git branch -D bisect
'

# This creates a "side" branch to test "siblings" cases.
#
# H1-H2-H3-H4-H5-H6-H7  <--other
#            \
#             S5-S6-S7  <--side
#
test_expect_success 'side branch creation' '
        git bisect reset &&
        git checkout -b side $HASH4 &&
        add_line_into_file "5(side): first line on a side branch" hello2 &&
        SIDE_HASH5=$(git rev-parse --verify HEAD) &&
        add_line_into_file "6(side): second line on a side branch" hello2 &&
        SIDE_HASH6=$(git rev-parse --verify HEAD) &&
        add_line_into_file "7(side): third line on a side branch" hello2 &&
        SIDE_HASH7=$(git rev-parse --verify HEAD)
'

test_expect_success 'good merge base when good and bad are siblings' '
        git bisect start "$HASH7" "$SIDE_HASH7" > my_bisect_log.txt &&
        grep "merge base must be tested" my_bisect_log.txt &&
        grep $HASH4 my_bisect_log.txt &&
        git bisect good > my_bisect_log.txt &&
        test_must_fail grep "merge base must be tested" my_bisect_log.txt &&
        grep $HASH6 my_bisect_log.txt &&
        git bisect reset
'
test_expect_success 'skipped merge base when good and bad are siblings' '
        git bisect start "$SIDE_HASH7" "$HASH7" > my_bisect_log.txt &&
        grep "merge base must be tested" my_bisect_log.txt &&
        grep $HASH4 my_bisect_log.txt &&
        git bisect skip > my_bisect_log.txt 2>&1 &&
        grep "Warning" my_bisect_log.txt &&
        grep $SIDE_HASH6 my_bisect_log.txt &&
        git bisect reset
'

test_expect_success 'bad merge base when good and bad are siblings' '
        git bisect start "$HASH7" HEAD > my_bisect_log.txt &&
        grep "merge base must be tested" my_bisect_log.txt &&
        grep $HASH4 my_bisect_log.txt &&
        test_must_fail git bisect bad > my_bisect_log.txt 2>&1 &&
        grep "merge base $HASH4 is bad" my_bisect_log.txt &&
        grep "fixed between $HASH4 and \[$SIDE_HASH7\]" my_bisect_log.txt &&
        git bisect reset
'

# This creates a few more commits (A and B) to test "siblings" cases
# when a good and a bad rev have many merge bases.
#
# We should have the following:
#
# H1-H2-H3-H4-H5-H6-H7
#            \  \     \
#             S5-A     \
#              \        \
#               S6-S7----B
#
# And there A and B have 2 merge bases (S5 and H5) that should be
# reported by "git merge-base --all A B".
#
test_expect_success 'many merge bases creation' '
        git checkout "$SIDE_HASH5" &&
        git merge -m "merge HASH5 and SIDE_HASH5" "$HASH5" &&
        A_HASH=$(git rev-parse --verify HEAD) &&
        git checkout side &&
        git merge -m "merge HASH7 and SIDE_HASH7" "$HASH7" &&
        B_HASH=$(git rev-parse --verify HEAD) &&
        git merge-base --all "$A_HASH" "$B_HASH" > merge_bases.txt &&
        test $(wc -l < merge_bases.txt) = "2" &&
        grep "$HASH5" merge_bases.txt &&
        grep "$SIDE_HASH5" merge_bases.txt
'

test_expect_success 'good merge bases when good and bad are siblings' '
        git bisect start "$B_HASH" "$A_HASH" > my_bisect_log.txt &&
        grep "merge base must be tested" my_bisect_log.txt &&
        git bisect good > my_bisect_log2.txt &&
        grep "merge base must be tested" my_bisect_log2.txt &&
        {
                {
                        grep "$SIDE_HASH5" my_bisect_log.txt &&
                        grep "$HASH5" my_bisect_log2.txt
                } || {
                        grep "$SIDE_HASH5" my_bisect_log2.txt &&
                        grep "$HASH5" my_bisect_log.txt
                }
        } &&
        git bisect reset
'

check_trace() {
        grep "$1" "$GIT_TRACE" | grep "\^$2" | grep "$3" >/dev/null
}

test_expect_success 'optimized merge base checks' '
        GIT_TRACE="$(pwd)/trace.log" &&
        export GIT_TRACE &&
        git bisect start "$HASH7" "$SIDE_HASH7" > my_bisect_log.txt &&
        grep "merge base must be tested" my_bisect_log.txt &&
        grep "$HASH4" my_bisect_log.txt &&
        check_trace "rev-list" "$HASH7" "$SIDE_HASH7" &&
        git bisect good > my_bisect_log2.txt &&
        test -f ".git/BISECT_ANCESTORS_OK" &&
        test "$HASH6" = $(git rev-parse --verify HEAD) &&
        : > "$GIT_TRACE" &&
        git bisect bad > my_bisect_log3.txt &&
        test_must_fail check_trace "rev-list" "$HASH6" "$SIDE_HASH7" &&
        git bisect good "$A_HASH" > my_bisect_log4.txt &&
        grep "merge base must be tested" my_bisect_log4.txt &&
        test_must_fail test -f ".git/BISECT_ANCESTORS_OK" &&
        check_trace "rev-list" "$HASH6" "$A_HASH" &&
        unset GIT_TRACE
'

#
#
test_done