git-commit-vandalism/t/t7800-difftool.sh
ZheNing Hu 1c881026a1 difftool.c: learn a new way start at specified file
`git difftool` only allow us to select file to view in turn.
If there is a commit with many files and we exit in the middle,
we will have to traverse list again to get the file diff which
we want to see. Therefore,teach the command an option
`--skip-to=<path>` to allow the user to say that diffs for earlier
paths are not interesting (because they were already seen in an
earlier session) and start this session with the named path.

Signed-off-by: ZheNing Hu <adlternative@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-22 13:35:49 -08:00

798 lines
22 KiB
Bash
Executable File

#!/bin/sh
#
# Copyright (c) 2009, 2010, 2012, 2013 David Aguilar
#
test_description='git-difftool
Testing basic diff tool invocation
'
GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
. ./test-lib.sh
difftool_test_setup ()
{
test_config diff.tool test-tool &&
test_config difftool.test-tool.cmd 'cat "$LOCAL"' &&
test_config difftool.bogus-tool.cmd false
}
prompt_given ()
{
prompt="$1"
test "$prompt" = "Launch 'test-tool' [Y/n]? branch"
}
test_expect_success 'basic usage requires no repo' '
test_expect_code 129 git difftool -h >output &&
test_i18ngrep ^usage: output &&
# create a ceiling directory to prevent Git from finding a repo
mkdir -p not/repo &&
test_when_finished rm -r not &&
test_expect_code 129 \
env GIT_CEILING_DIRECTORIES="$(pwd)/not" \
git -C not/repo difftool -h >output &&
test_i18ngrep ^usage: output
'
# Create a file on main and change it on branch
test_expect_success 'setup' '
echo main >file &&
git add file &&
git commit -m "added file" &&
git checkout -b branch main &&
echo branch >file &&
git commit -a -m "branch changed file" &&
git checkout main
'
# Configure a custom difftool.<tool>.cmd and use it
test_expect_success 'custom commands' '
difftool_test_setup &&
test_config difftool.test-tool.cmd "cat \"\$REMOTE\"" &&
echo main >expect &&
git difftool --no-prompt branch >actual &&
test_cmp expect actual &&
test_config difftool.test-tool.cmd "cat \"\$LOCAL\"" &&
echo branch >expect &&
git difftool --no-prompt branch >actual &&
test_cmp expect actual
'
test_expect_success 'custom tool commands override built-ins' '
test_config difftool.vimdiff.cmd "cat \"\$REMOTE\"" &&
echo main >expect &&
git difftool --tool vimdiff --no-prompt branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool ignores bad --tool values' '
: >expect &&
test_must_fail \
git difftool --no-prompt --tool=bad-tool branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool forwards arguments to diff' '
difftool_test_setup &&
>for-diff &&
git add for-diff &&
echo changes>for-diff &&
git add for-diff &&
: >expect &&
git difftool --cached --no-prompt -- for-diff >actual &&
test_cmp expect actual &&
git reset -- for-diff &&
rm for-diff
'
test_expect_success 'difftool ignores exit code' '
test_config difftool.error.cmd false &&
git difftool -y -t error branch
'
test_expect_success 'difftool forwards exit code with --trust-exit-code' '
test_config difftool.error.cmd false &&
test_must_fail git difftool -y --trust-exit-code -t error branch
'
test_expect_success 'difftool forwards exit code with --trust-exit-code for built-ins' '
test_config difftool.vimdiff.path false &&
test_must_fail git difftool -y --trust-exit-code -t vimdiff branch
'
test_expect_success 'difftool honors difftool.trustExitCode = true' '
test_config difftool.error.cmd false &&
test_config difftool.trustExitCode true &&
test_must_fail git difftool -y -t error branch
'
test_expect_success 'difftool honors difftool.trustExitCode = false' '
test_config difftool.error.cmd false &&
test_config difftool.trustExitCode false &&
git difftool -y -t error branch
'
test_expect_success 'difftool ignores exit code with --no-trust-exit-code' '
test_config difftool.error.cmd false &&
test_config difftool.trustExitCode true &&
git difftool -y --no-trust-exit-code -t error branch
'
test_expect_success 'difftool stops on error with --trust-exit-code' '
test_when_finished "rm -f for-diff .git/fail-right-file" &&
test_when_finished "git reset -- for-diff" &&
write_script .git/fail-right-file <<-\EOF &&
echo failed
exit 1
EOF
>for-diff &&
git add for-diff &&
test_must_fail git difftool -y --trust-exit-code \
--extcmd .git/fail-right-file branch >actual &&
test_line_count = 1 actual
'
test_expect_success 'difftool honors exit status if command not found' '
test_config difftool.nonexistent.cmd i-dont-exist &&
test_config difftool.trustExitCode false &&
test_must_fail git difftool -y -t nonexistent branch
'
test_expect_success 'difftool honors --gui' '
difftool_test_setup &&
test_config merge.tool bogus-tool &&
test_config diff.tool bogus-tool &&
test_config diff.guitool test-tool &&
echo branch >expect &&
git difftool --no-prompt --gui branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --gui last setting wins' '
difftool_test_setup &&
: >expect &&
git difftool --no-prompt --gui --no-gui >actual &&
test_cmp expect actual &&
test_config merge.tool bogus-tool &&
test_config diff.tool bogus-tool &&
test_config diff.guitool test-tool &&
echo branch >expect &&
git difftool --no-prompt --no-gui --gui branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --gui works without configured diff.guitool' '
difftool_test_setup &&
echo branch >expect &&
git difftool --no-prompt --gui branch >actual &&
test_cmp expect actual
'
# Specify the diff tool using $GIT_DIFF_TOOL
test_expect_success 'GIT_DIFF_TOOL variable' '
difftool_test_setup &&
git config --unset diff.tool &&
echo branch >expect &&
GIT_DIFF_TOOL=test-tool git difftool --no-prompt branch >actual &&
test_cmp expect actual
'
# Test the $GIT_*_TOOL variables and ensure
# that $GIT_DIFF_TOOL always wins unless --tool is specified
test_expect_success 'GIT_DIFF_TOOL overrides' '
difftool_test_setup &&
test_config diff.tool bogus-tool &&
test_config merge.tool bogus-tool &&
echo branch >expect &&
GIT_DIFF_TOOL=test-tool git difftool --no-prompt branch >actual &&
test_cmp expect actual &&
test_config diff.tool bogus-tool &&
test_config merge.tool bogus-tool &&
GIT_DIFF_TOOL=bogus-tool \
git difftool --no-prompt --tool=test-tool branch >actual &&
test_cmp expect actual
'
# Test that we don't have to pass --no-prompt to difftool
# when $GIT_DIFFTOOL_NO_PROMPT is true
test_expect_success 'GIT_DIFFTOOL_NO_PROMPT variable' '
difftool_test_setup &&
echo branch >expect &&
GIT_DIFFTOOL_NO_PROMPT=true git difftool branch >actual &&
test_cmp expect actual
'
# git-difftool supports the difftool.prompt variable.
# Test that GIT_DIFFTOOL_PROMPT can override difftool.prompt = false
test_expect_success 'GIT_DIFFTOOL_PROMPT variable' '
difftool_test_setup &&
test_config difftool.prompt false &&
echo >input &&
GIT_DIFFTOOL_PROMPT=true git difftool branch <input >output &&
prompt=$(tail -1 <output) &&
prompt_given "$prompt"
'
# Test that we don't have to pass --no-prompt when difftool.prompt is false
test_expect_success 'difftool.prompt config variable is false' '
difftool_test_setup &&
test_config difftool.prompt false &&
echo branch >expect &&
git difftool branch >actual &&
test_cmp expect actual
'
# Test that we don't have to pass --no-prompt when mergetool.prompt is false
test_expect_success 'difftool merge.prompt = false' '
difftool_test_setup &&
test_might_fail git config --unset difftool.prompt &&
test_config mergetool.prompt false &&
echo branch >expect &&
git difftool branch >actual &&
test_cmp expect actual
'
# Test that the -y flag can override difftool.prompt = true
test_expect_success 'difftool.prompt can overridden with -y' '
difftool_test_setup &&
test_config difftool.prompt true &&
echo branch >expect &&
git difftool -y branch >actual &&
test_cmp expect actual
'
# Test that the --prompt flag can override difftool.prompt = false
test_expect_success 'difftool.prompt can overridden with --prompt' '
difftool_test_setup &&
test_config difftool.prompt false &&
echo >input &&
git difftool --prompt branch <input >output &&
prompt=$(tail -1 <output) &&
prompt_given "$prompt"
'
# Test that the last flag passed on the command-line wins
test_expect_success 'difftool last flag wins' '
difftool_test_setup &&
echo branch >expect &&
git difftool --prompt --no-prompt branch >actual &&
test_cmp expect actual &&
echo >input &&
git difftool --no-prompt --prompt branch <input >output &&
prompt=$(tail -1 <output) &&
prompt_given "$prompt"
'
# git-difftool falls back to git-mergetool config variables
# so test that behavior here
test_expect_success 'difftool + mergetool config variables' '
test_config merge.tool test-tool &&
test_config mergetool.test-tool.cmd "cat \$LOCAL" &&
echo branch >expect &&
git difftool --no-prompt branch >actual &&
test_cmp expect actual &&
git difftool --gui --no-prompt branch >actual &&
test_cmp expect actual &&
# set merge.tool to something bogus, diff.tool to test-tool
test_config merge.tool bogus-tool &&
test_config diff.tool test-tool &&
git difftool --no-prompt branch >actual &&
test_cmp expect actual &&
git difftool --gui --no-prompt branch >actual &&
test_cmp expect actual &&
# set merge.tool, diff.tool to something bogus, merge.guitool to test-tool
test_config diff.tool bogus-tool &&
test_config merge.guitool test-tool &&
git difftool --gui --no-prompt branch >actual &&
test_cmp expect actual &&
# set merge.tool, diff.tool, merge.guitool to something bogus, diff.guitool to test-tool
test_config merge.guitool bogus-tool &&
test_config diff.guitool test-tool &&
git difftool --gui --no-prompt branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool.<tool>.path' '
test_config difftool.tkdiff.path echo &&
git difftool --tool=tkdiff --no-prompt branch >output &&
grep file output >grep-output &&
test_line_count = 1 grep-output
'
test_expect_success 'difftool --extcmd=cat' '
echo branch >expect &&
echo main >>expect &&
git difftool --no-prompt --extcmd=cat branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --extcmd cat' '
echo branch >expect &&
echo main >>expect &&
git difftool --no-prompt --extcmd=cat branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool -x cat' '
echo branch >expect &&
echo main >>expect &&
git difftool --no-prompt -x cat branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --extcmd echo arg1' '
echo file >expect &&
git difftool --no-prompt \
--extcmd sh\ -c\ \"echo\ \$1\" branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --extcmd cat arg1' '
echo main >expect &&
git difftool --no-prompt \
--extcmd sh\ -c\ \"cat\ \$1\" branch >actual &&
test_cmp expect actual
'
test_expect_success 'difftool --extcmd cat arg2' '
echo branch >expect &&
git difftool --no-prompt \
--extcmd sh\ -c\ \"cat\ \\\"\$2\\\"\" branch >actual &&
test_cmp expect actual
'
# Create a second file on main and a different version on branch
test_expect_success 'setup with 2 files different' '
echo m2 >file2 &&
git add file2 &&
git commit -m "added file2" &&
git checkout branch &&
echo br2 >file2 &&
git add file2 &&
git commit -a -m "branch changed file2" &&
git checkout main
'
test_expect_success 'say no to the first file' '
(echo n && echo) >input &&
git difftool -x cat branch <input >output &&
grep m2 output &&
grep br2 output &&
! grep main output &&
! grep branch output
'
test_expect_success 'say no to the second file' '
(echo && echo n) >input &&
git difftool -x cat branch <input >output &&
grep main output &&
grep branch output &&
! grep m2 output &&
! grep br2 output
'
test_expect_success 'ending prompt input with EOF' '
git difftool -x cat branch </dev/null >output &&
! grep main output &&
! grep branch output &&
! grep m2 output &&
! grep br2 output
'
test_expect_success 'difftool --tool-help' '
git difftool --tool-help >output &&
grep tool output
'
test_expect_success 'setup change in subdirectory' '
git checkout main &&
mkdir sub &&
echo main >sub/sub &&
git add sub/sub &&
git commit -m "added sub/sub" &&
git tag v1 &&
echo test >>file &&
echo test >>sub/sub &&
git add file sub/sub &&
git commit -m "modified both"
'
test_expect_success 'difftool -d with growing paths' '
a=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa &&
git init growing &&
(
cd growing &&
echo "test -f \"\$2/b\"" | write_script .git/test-for-b.sh &&
one=$(printf 1 | git hash-object -w --stdin) &&
two=$(printf 2 | git hash-object -w --stdin) &&
git update-index --add \
--cacheinfo 100644,$one,$a --cacheinfo 100644,$two,b &&
tree1=$(git write-tree) &&
git update-index --add \
--cacheinfo 100644,$two,$a --cacheinfo 100644,$one,b &&
tree2=$(git write-tree) &&
git checkout -- $a &&
git difftool -d --extcmd .git/test-for-b.sh $tree1 $tree2
)
'
run_dir_diff_test () {
test_expect_success "$1 --no-symlinks" "
symlinks=--no-symlinks &&
$2
"
test_expect_success SYMLINKS "$1 --symlinks" "
symlinks=--symlinks &&
$2
"
}
run_dir_diff_test 'difftool -d' '
git difftool -d $symlinks --extcmd ls branch >output &&
grep "^sub$" output &&
grep "^file$" output
'
run_dir_diff_test 'difftool --dir-diff' '
git difftool --dir-diff $symlinks --extcmd ls branch >output &&
grep "^sub$" output &&
grep "^file$" output
'
run_dir_diff_test 'difftool --dir-diff ignores --prompt' '
git difftool --dir-diff $symlinks --prompt --extcmd ls branch >output &&
grep "^sub$" output &&
grep "^file$" output
'
run_dir_diff_test 'difftool --dir-diff branch from subdirectory' '
(
cd sub &&
git difftool --dir-diff $symlinks --extcmd ls branch >output &&
# "sub" must only exist in "right"
# "file" and "file2" must be listed in both "left" and "right"
grep "^sub$" output >sub-output &&
test_line_count = 1 sub-output &&
grep "^file$" output >file-output &&
test_line_count = 2 file-output &&
grep "^file2$" output >file2-output &&
test_line_count = 2 file2-output
)
'
run_dir_diff_test 'difftool --dir-diff v1 from subdirectory' '
(
cd sub &&
git difftool --dir-diff $symlinks --extcmd ls v1 >output &&
# "sub" and "file" exist in both v1 and HEAD.
# "file2" is unchanged.
grep "^sub$" output >sub-output &&
test_line_count = 2 sub-output &&
grep "^file$" output >file-output &&
test_line_count = 2 file-output &&
! grep "^file2$" output
)
'
run_dir_diff_test 'difftool --dir-diff branch from subdirectory w/ pathspec' '
(
cd sub &&
git difftool --dir-diff $symlinks --extcmd ls branch -- .>output &&
# "sub" only exists in "right"
# "file" and "file2" must not be listed
grep "^sub$" output >sub-output &&
test_line_count = 1 sub-output &&
! grep "^file$" output
)
'
run_dir_diff_test 'difftool --dir-diff v1 from subdirectory w/ pathspec' '
(
cd sub &&
git difftool --dir-diff $symlinks --extcmd ls v1 -- .>output &&
# "sub" exists in v1 and HEAD
# "file" is filtered out by the pathspec
grep "^sub$" output >sub-output &&
test_line_count = 2 sub-output &&
! grep "^file$" output
)
'
run_dir_diff_test 'difftool --dir-diff from subdirectory with GIT_DIR set' '
(
GIT_DIR=$(pwd)/.git &&
export GIT_DIR &&
GIT_WORK_TREE=$(pwd) &&
export GIT_WORK_TREE &&
cd sub &&
git difftool --dir-diff $symlinks --extcmd ls \
branch -- sub >output &&
grep "^sub$" output &&
! grep "^file$" output
)
'
run_dir_diff_test 'difftool --dir-diff when worktree file is missing' '
test_when_finished git reset --hard &&
rm file2 &&
git difftool --dir-diff $symlinks --extcmd ls branch main >output &&
grep "^file2$" output
'
run_dir_diff_test 'difftool --dir-diff with unmerged files' '
test_when_finished git reset --hard &&
test_config difftool.echo.cmd "echo ok" &&
git checkout -B conflict-a &&
git checkout -B conflict-b &&
git checkout conflict-a &&
echo a >>file &&
git add file &&
git commit -m conflict-a &&
git checkout conflict-b &&
echo b >>file &&
git add file &&
git commit -m conflict-b &&
git checkout main &&
git merge conflict-a &&
test_must_fail git merge conflict-b &&
cat >expect <<-EOF &&
ok
EOF
git difftool --dir-diff $symlinks -t echo >actual &&
test_cmp expect actual
'
write_script .git/CHECK_SYMLINKS <<\EOF
for f in file file2 sub/sub
do
echo "$f"
ls -ld "$2/$f" | sed -e 's/.* -> //'
done >actual
EOF
test_expect_success SYMLINKS 'difftool --dir-diff --symlinks without unstaged changes' '
cat >expect <<-EOF &&
file
$PWD/file
file2
$PWD/file2
sub/sub
$PWD/sub/sub
EOF
git difftool --dir-diff --symlinks \
--extcmd "./.git/CHECK_SYMLINKS" branch HEAD &&
test_cmp expect actual
'
write_script modify-right-file <<\EOF
echo "new content" >"$2/file"
EOF
run_dir_diff_test 'difftool --dir-diff syncs worktree with unstaged change' '
test_when_finished git reset --hard &&
echo "orig content" >file &&
git difftool -d $symlinks --extcmd "$PWD/modify-right-file" branch &&
echo "new content" >expect &&
test_cmp expect file
'
run_dir_diff_test 'difftool --dir-diff syncs worktree without unstaged change' '
test_when_finished git reset --hard &&
git difftool -d $symlinks --extcmd "$PWD/modify-right-file" branch &&
echo "new content" >expect &&
test_cmp expect file
'
write_script modify-file <<\EOF
echo "new content" >file
EOF
test_expect_success 'difftool --no-symlinks does not overwrite working tree file ' '
echo "orig content" >file &&
git difftool --dir-diff --no-symlinks --extcmd "$PWD/modify-file" branch &&
echo "new content" >expect &&
test_cmp expect file
'
write_script modify-both-files <<\EOF
echo "wt content" >file &&
echo "tmp content" >"$2/file" &&
echo "$2" >tmpdir
EOF
test_expect_success 'difftool --no-symlinks detects conflict ' '
(
TMPDIR=$TRASH_DIRECTORY &&
export TMPDIR &&
echo "orig content" >file &&
test_must_fail git difftool --dir-diff --no-symlinks --extcmd "$PWD/modify-both-files" branch &&
echo "wt content" >expect &&
test_cmp expect file &&
echo "tmp content" >expect &&
test_cmp expect "$(cat tmpdir)/file"
)
'
test_expect_success 'difftool properly honors gitlink and core.worktree' '
test_when_finished rm -rf submod/ule &&
git submodule add ./. submod/ule &&
test_config -C submod/ule diff.tool checktrees &&
test_config -C submod/ule difftool.checktrees.cmd '\''
test -d "$LOCAL" && test -d "$REMOTE" && echo good
'\'' &&
(
cd submod/ule &&
echo good >expect &&
git difftool --tool=checktrees --dir-diff HEAD~ >actual &&
test_cmp expect actual &&
rm -f expect actual
)
'
test_expect_success SYMLINKS 'difftool --dir-diff symlinked directories' '
test_when_finished git reset --hard &&
git init dirlinks &&
(
cd dirlinks &&
git config diff.tool checktrees &&
git config difftool.checktrees.cmd "echo good" &&
mkdir foo &&
: >foo/bar &&
git add foo/bar &&
test_commit symlink-one &&
ln -s foo link &&
git add link &&
test_commit symlink-two &&
echo good >expect &&
git difftool --tool=checktrees --dir-diff HEAD~ >actual &&
test_cmp expect actual
)
'
test_expect_success SYMLINKS 'difftool --dir-diff handles modified symlinks' '
test_when_finished git reset --hard &&
touch b &&
ln -s b c &&
git add b c &&
test_tick &&
git commit -m initial &&
touch d &&
rm c &&
ln -s d c &&
cat >expect <<-EOF &&
b
c
c
EOF
git difftool --symlinks --dir-diff --extcmd ls >output &&
grep -v ^/ output >actual &&
test_cmp expect actual &&
git difftool --no-symlinks --dir-diff --extcmd ls >output &&
grep -v ^/ output >actual &&
test_cmp expect actual &&
# The left side contains symlink "c" that points to "b"
test_config difftool.cat.cmd "cat \$LOCAL/c" &&
printf "%s\n" b >expect &&
git difftool --symlinks --dir-diff --tool cat >actual &&
test_cmp expect actual &&
git difftool --symlinks --no-symlinks --dir-diff --tool cat >actual &&
test_cmp expect actual &&
# The right side contains symlink "c" that points to "d"
test_config difftool.cat.cmd "cat \$REMOTE/c" &&
printf "%s\n" d >expect &&
git difftool --symlinks --dir-diff --tool cat >actual &&
test_cmp expect actual &&
git difftool --no-symlinks --dir-diff --tool cat >actual &&
test_cmp expect actual &&
# Deleted symlinks
rm -f c &&
cat >expect <<-EOF &&
b
c
EOF
git difftool --symlinks --dir-diff --extcmd ls >output &&
grep -v ^/ output >actual &&
test_cmp expect actual &&
git difftool --no-symlinks --dir-diff --extcmd ls >output &&
grep -v ^/ output >actual &&
test_cmp expect actual
'
test_expect_success 'add -N and difftool -d' '
test_when_finished git reset --hard &&
test_write_lines A B C >intent-to-add &&
git add -N intent-to-add &&
git difftool --dir-diff --extcmd ls
'
test_expect_success 'difftool --cached with unmerged files' '
test_when_finished git reset --hard &&
test_commit conflicting &&
test_commit conflict-a conflict.t a &&
git reset --hard conflicting &&
test_commit conflict-b conflict.t b &&
test_must_fail git merge conflict-a &&
git difftool --cached --no-prompt >output &&
test_must_be_empty output
'
test_expect_success 'outside worktree' '
echo 1 >1 &&
echo 2 >2 &&
test_expect_code 1 nongit git \
-c diff.tool=echo -c difftool.echo.cmd="echo \$LOCAL \$REMOTE" \
difftool --no-prompt --no-index ../1 ../2 >actual &&
echo "../1 ../2" >expect &&
test_cmp expect actual
'
test_expect_success 'difftool --gui, --tool and --extcmd are mutually exclusive' '
difftool_test_setup &&
test_must_fail git difftool --gui --tool=test-tool &&
test_must_fail git difftool --gui --extcmd=cat &&
test_must_fail git difftool --tool=test-tool --extcmd=cat &&
test_must_fail git difftool --gui --tool=test-tool --extcmd=cat
'
test_expect_success 'difftool --rotate-to' '
difftool_test_setup &&
test_when_finished git reset --hard &&
echo 1 >1 &&
echo 2 >2 &&
echo 4 >4 &&
git add 1 2 4 &&
git commit -a -m "124" &&
git difftool --no-prompt --extcmd=cat --rotate-to="2" HEAD^ >output&&
cat >expect <<-\EOF &&
2
4
1
EOF
test_cmp output expect
'
test_expect_success 'difftool --skip-to' '
difftool_test_setup &&
test_when_finished git reset --hard &&
git difftool --no-prompt --extcmd=cat --skip-to="2" HEAD^ >output &&
cat >expect <<-\EOF &&
2
4
EOF
test_cmp output expect
'
test_expect_success 'difftool --rotate/skip-to error condition' '
test_must_fail git difftool --no-prompt --extcmd=cat --rotate-to="3" HEAD^ &&
test_must_fail git difftool --no-prompt --extcmd=cat --skip-to="3" HEAD^
'
test_done