patchmv: let 'git mv file no-such-dir/' error out

> Git used to trim the trailing slash, and make the command equivalent to
> 'git mv file no-such-dir', which created the file no-such-dir (while the
> trailing slash explicitly stated that it could only be a directory).
>
> This patch skips the trailing slash removal for the destination path. The
> path with its trailing slash is passed to rename(2), which errors out
> with the appropriate message:
>
>   $ git mv file no-such-dir/
>   fatal: renaming 'file' failed: Not a directory

> Original-patch-by: Duy Nguyen <pclouds@gmail.com>
> Tests, tweaks and commit message by: Matthieu Moy <Matthieu.Moy@imag.fr>
>
> Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
> ---
>  builtin/mv.c  | 23 ++++++++++++++++-------
>  t/t7001-mv.sh | 10 ++++++++++
>  2 files changed, 26 insertions(+), 7 deletions(-)
>
> diff --git a/builtin/mv.c b/builtin/mv.c
> index 2e0e61b..08fbc03 100644
> --- a/builtin/mv.c
> +++ b/builtin/mv.c
> @@ -16,9 +16,12 @@ static const char * const builtin_mv_usage[] = {
>         NULL
>  };
>
> +#define DUP_BASENAME 1
> +#define KEEP_TRAILING_SLASH 2
> +
>  static const char **internal_copy_pathspec(const char *prefix,
>                                            const char **pathspec,
> -                                          int count, int base_name)
> +                                          int count, unsigned flags)
>  {
>         int i;
>         const char **result = xmalloc((count + 1) * sizeof(const char *));
> @@ -27,11 +30,12 @@ static const char **internal_copy_pathspec(const char *prefix,
>         for (i = 0; i < count; i++) {
>                 int length = strlen(result[i]);
>                 int to_copy = length;
> -               while (to_copy > 0 && is_dir_sep(result[i][to_copy - 1]))
> +               while (!(flags & KEEP_TRAILING_SLASH) &&
> +                      to_copy > 0 && is_dir_sep(result[i][to_copy - 1]))
>                         to_copy--;
> -               if (to_copy != length || base_name) {
> +               if (to_copy != length || flags & DUP_BASENAME) {
>                         char *it = xmemdupz(result[i], to_copy);
> -                       if (base_name) {
> +                       if (flags & DUP_BASENAME) {
>                                 result[i] = xstrdup(basename(it));
>                                 free(it);
>                         } else
> @@ -87,16 +91,21 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
>
>         source = internal_copy_pathspec(prefix, argv, argc, 0);
>         modes = xcalloc(argc, sizeof(enum update_mode));
> -       dest_path = internal_copy_pathspec(prefix, argv + argc, 1, 0);
> +       /*
> +        * Keep trailing slash, needed to let
> +        * "git mv file no-such-dir/" error out.
> +        */
> +       dest_path = internal_copy_pathspec(prefix, argv + argc, 1,
> +                                          KEEP_TRAILING_SLASH);
>         submodule_gitfile = xcalloc(argc, sizeof(char *));
>
>         if (dest_path[0][0] == '\0')
>                 /* special case: "." was normalized to "" */
> -               destination = internal_copy_pathspec(dest_path[0], argv, argc, 1);
> +               destination = internal_copy_pathspec(dest_path[0], argv, argc, DUP_BASENAME);
>         else if (!lstat(dest_path[0], &st) &&
>                         S_ISDIR(st.st_mode)) {
>                 dest_path[0] = add_slash(dest_path[0]);
> -               destination = internal_copy_pathspec(dest_path[0], argv, argc, 1);
> +               destination = internal_copy_pathspec(dest_path[0], argv, argc, DUP_BASENAME);
>         } else {
>                 if (argc != 1)
>                         die("destination '%s' is not a directory", dest_path[0]);
> diff --git a/t/t7001-mv.sh b/t/t7001-mv.sh
> index b90e985..e5c8084 100755
> --- a/t/t7001-mv.sh
> +++ b/t/t7001-mv.sh
> @@ -72,6 +72,16 @@ rm -f idontexist untracked1 untracked2 \
>       .git/index.lock
>
>  test_expect_success \
> +    'moving to target with trailing slash' \
> +    'test_must_fail git mv path0/COPYING no-such-dir/ &&
> +     test_must_fail git mv path0/COPYING no-such-dir// &&
> +     git mv path0/ no-such-dir/'
> +
> +test_expect_success \
> +    'clean up' \
> +    'git reset --hard'
> +
> +test_expect_success \
>      'adding another file' \
>      'cp "$TEST_DIRECTORY"/../README path0/README &&
>       git add path0/README &&
> --
> 1.8.5.rc3.4.g8bd3721
>

> On Tue, Dec 3, 2013 at 3:32 PM, Matthieu Moy <Matthieu.Moy@imag.fr> wrote:
>> Git used to trim the trailing slash, and make the command equivalent to
>> 'git mv file no-such-dir', which created the file no-such-dir (while the
>> trailing slash explicitly stated that it could only be a directory).
>>
>> This patch skips the trailing slash removal for the destination path. The
>> path with its trailing slash is passed to rename(2), which errors out
>> with the appropriate message:
>>
>>   $ git mv file no-such-dir/
>>   fatal: renaming 'file' failed: Not a directory
>
> There's something we probably should check. In d78b0f3 ([PATCH]
> git-mv: add more path normalization - 2006-08-16), it mentions about
>
> git mv something/ somewhere/
>
> there's no test in that commit so I don't know the actual input and
> expected outcome.

> Duy Nguyen <pclouds@gmail.com> writes:
>
>> On Tue, Dec 3, 2013 at 3:32 PM, Matthieu Moy <Matthieu.Moy@imag.fr> wrote:
>> There's something we probably should check. In d78b0f3 ([PATCH]
>> git-mv: add more path normalization - 2006-08-16), it mentions about
>>
>> git mv something/ somewhere/
>>
>> there's no test in that commit so I don't know the actual input and
>> expected outcome.
>
> To me, the expected outcome is "behave like Unix's mv" (which works with
> or without the trailing slash if somewhere exists).
>
>> If "somewhere" is a directory, it errors out with this patch and works
>> without it.
>
> I can't reproduce. I've added this to my patch (indeed, the area wasn't
> well tested), and the tests pass.

> On Wed, Dec 4, 2013 at 3:44 PM, Matthieu Moy
> <Matthieu.Moy@grenoble-inp.fr> wrote:
>> Duy Nguyen <pclouds@gmail.com> writes:
>>
>>> On Tue, Dec 3, 2013 at 3:32 PM, Matthieu Moy <Matthieu.Moy@imag.fr> wrote:
>>> There's something we probably should check. In d78b0f3 ([PATCH]
>>> git-mv: add more path normalization - 2006-08-16), it mentions about
>>>
>>> git mv something/ somewhere/
>>>
>>> there's no test in that commit so I don't know the actual input and
>>> expected outcome.
>>
>> To me, the expected outcome is "behave like Unix's mv" (which works with
>> or without the trailing slash if somewhere exists).
>>
>>> If "somewhere" is a directory, it errors out with this patch and works
>>> without it.
>>
>> I can't reproduce. I've added this to my patch (indeed, the area wasn't
>> well tested), and the tests pass.
>
> Now I can't either. Probably some mis-setups or some local bugs in my
> tree. Good that we have more tests.

> This changes the error message from
>
>    $ git mv file no-such-dir/
>    fatal: renaming 'file' failed: Not a directory
>
> to
>
>    $ git mv file no-such-dir/
>    fatal: destination directory does not exist, source=file, destination=no-such-dir/
>
> Signed-off-by: Johannes Sixt <j6t@kdbg.org>
> ---
>  builtin/mv.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/builtin/mv.c b/builtin/mv.c
> index 08fbc03..21c46d1 100644
> --- a/builtin/mv.c
> +++ b/builtin/mv.c
> @@ -214,6 +214,8 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
>  			}
>  		} else if (string_list_has_string(&src_for_dst, dst))
>  			bad = _("multiple sources for the same target");
> +		else if (is_dir_sep(dst[strlen(dst) - 1]))
> +			bad = _("destination directory does not exist");
>  		else
>  			string_list_insert(&src_for_dst, dst);

> Johannes Sixt <j6t@kdbg.org> writes:
> 
>> The previous commit c57f628 (mv: let 'git mv file no-such-dir/' error out)
>> relies on that rename("src", "dst/") fails if directory dst does not
>> exist (note the trailing slash). This does not work as expected on Windows:
>> This rename() call is successful. Insert an explicit check for this case.
> 
> Could you care to explain "Successful how" a bit here?  Do we see
> no-such-dir mkdir'ed and then no-such-dir/file created?  Do we see
> file moved to a new file whose name is no-such-dir/?  I am guessing
> that it would be the latter, but if that is the case we would need
> at least an air-quote around "successful".

> 
>> This changes the error message from
>>
>>    $ git mv file no-such-dir/
>>    fatal: renaming 'file' failed: Not a directory
>>
>> to
>>
>>    $ git mv file no-such-dir/
>>    fatal: destination directory does not exist, source=file, destination=no-such-dir/
>>
>> Signed-off-by: Johannes Sixt <j6t@kdbg.org>
>> ---
>>  builtin/mv.c | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/builtin/mv.c b/builtin/mv.c
>> index 08fbc03..21c46d1 100644
>> --- a/builtin/mv.c
>> +++ b/builtin/mv.c
>> @@ -214,6 +214,8 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
>>  			}
>>  		} else if (string_list_has_string(&src_for_dst, dst))
>>  			bad = _("multiple sources for the same target");
>> +		else if (is_dir_sep(dst[strlen(dst) - 1]))
>> +			bad = _("destination directory does not exist");
>>  		else
>>  			string_list_insert(&src_for_dst, dst);
> 

> The file is renamed to no-such-dir without the slash at the end. The
> updated commit message would be:
>
> mv: let 'git mv file no-such-dir/' error out on Windows, too
>
> The previous commit c57f628 (mv: let 'git mv file no-such-dir/' error out)
> relies on that rename("src", "dst/") fails if directory dst does not
> exist (note the trailing slash). This does not work as expected on Windows:
> The rename() call does not fail, but renames src to dst (without the
> trailing slash). Insert an explicit check for this case to force an error.
>
> This changes the error message from
>
>    $ git mv file no-such-dir/
>    fatal: renaming 'file' failed: Not a directory
>
> to
>
>    $ git mv file no-such-dir/
>    fatal: destination directory does not exist, source=file, destination=no-such-dir/
>
> Signed-off-by: Johannes Sixt <j6t@kdbg.org>