git check-ignore --verbose fails oddly when invoked via an alias

Hello all,

I have some bizarre behavior I cannot explain. Worse, I've had a hard time coming up with a minimal test-case for it.

I have the following two aliases:

    ig = check-ignore
    igv = !git ig --verbose

I use them to verify git-ignore rules occasionally. Today, I was working on a project where git igv * kept failing (exit code 1, indicating none of the provided files are ignored). However, when I do git check-ignore --verbose *, I get the expected output.

You'll even see in the GIT_TRACE outputs above that one behaves very differently from the other for unknown reasons

Debugging information:

$ pwd
/Users/Knoble/write/junk-drawer/code
$ g rev-parse --show-toplevel
/Users/Knoble/write/junk-drawer
$ tree -a sml-binary
sml-binary/
├── .cm
│   ├── GUID
│   │   └── myprog.sml
│   ├── SKEL
│   │   └── myprog.sml
│   └── amd64-unix
│       └── myprog.sml
├── .gitignore
├── Makefile
├── myprog
├── myprog.amd64-darwin
├── myprog.cm
├── myprog.sml
└── tmp
    ├── bin
    │   └── myprog
    └── lib
        └── myprog.amd64-darwin

7 directories, 11 files $ cat sml-binary/.gitignore myprog myprog.amd64-darwin $ g check-ignore sml-binary/* sml-binary/myprog sml-binary/myprog.amd64-darwin $ g check-ignore --verbose sml-binary/* code/sml-binary/.gitignore:1:myprog sml-binary/myprog code/sml-binary/.gitignore:2:myprog.amd64-darwin sml-binary/myprog.amd64-darwin $ g ig sml-binary/* sml-binary/myprog sml-binary/myprog.amd64-darwin $ g igv sml-binary/* $ echo $? 1 $ pushd sml-binary/ ~/write/junk-drawer/code/sml-binary ~/write/junk-drawer/code ~/write/junk-drawer/code/sml-binary $ g ig * myprog myprog.amd64-darwin $ g ig --verbose * code/sml-binary/.gitignore:1:myprog myprog code/sml-binary/.gitignore:2:myprog.amd64-darwin myprog.amd64-darwin $ g igv * $ echo $? 1 $ GIT_TRACE2=2 g igv * 15:48:21.773549 common-main.c:48 version 2.26.2 15:48:21.773904 common-main.c:49 start git igv Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.774443 git.c:697 cmd_name _run_dashed_ (_run_dashed_) 15:48:21.774473 run-command.c:735 child_start[0] git-igv Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.774735 run-command.c:950 child_exit[0] pid:-1 code:-1 elapsed:0.000249 15:48:21.775368 repository.c:130 worktree /Users/Knoble/write/junk-drawer 15:48:21.775427 git.c:352 alias igv -> 'git ig --verbose' Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.775439 git.c:354 cmd_name _run_shell_alias_ (_run_dashed_/_run_shell_alias_) 15:48:21.775445 run-command.c:735 child_start[1] 'git ig --verbose' Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.786123 common-main.c:48 version 2.26.2 15:48:21.786579 common-main.c:49 start git ig --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.787201 git.c:697 cmd_name _run_dashed_ (_run_dashed_/_run_shell_alias_/_run_dashed_) 15:48:21.787243 run-command.c:735 child_start[0] git-ig --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.787464 run-command.c:950 child_exit[0] pid:-1 code:-1 elapsed:0.000216 15:48:21.787781 git.c:389 alias ig -> check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.787794 git.c:753 cmd_name _run_git_alias_ (_run_dashed_/_run_shell_alias_/_run_dashed_/_run_git_alias_) 15:48:21.787801 run-command.c:735 child_start[1] git check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.793959 common-main.c:48 version 2.26.2 15:48:21.794206 common-main.c:49 start /usr/local/Cellar/git/2.26.2/libexec/git-core/git check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:48:21.794427 repository.c:130 worktree /Users/Knoble/write/junk-drawer 15:48:21.794671 git.c:440 cmd_name check-ignore (_run_dashed_/_run_shell_alias_/_run_dashed_/_run_git_alias_/check-ignore) 15:48:21.795513 git.c:674 exit elapsed:0.003100 code:1 15:48:21.795529 trace2/tr2_tgt_normal.c:123 atexit elapsed:0.003121 code:1 15:48:21.795935 run-command.c:990 child_exit[1] pid:98684 code:1 elapsed:0.008108 15:48:21.795971 git.c:773 exit elapsed:0.012124 code:1 15:48:21.795995 trace2/tr2_tgt_normal.c:123 atexit elapsed:0.012139 code:1 15:48:21.796351 run-command.c:990 child_exit[1] pid:98683 code:1 elapsed:0.020896 15:48:21.796391 git.c:358 exit elapsed:0.024746 code:1 15:48:21.796416 trace2/tr2_tgt_normal.c:123 atexit elapsed:0.024761 code:1 $ GIT_TRACE2=2 g ig --verbose * 15:57:42.274337 common-main.c:48 version 2.26.2 15:57:42.274640 common-main.c:49 start git ig --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:57:42.275146 git.c:697 cmd_name _run_dashed_ (_run_dashed_) 15:57:42.275167 run-command.c:735 child_start[0] git-ig --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:57:42.275422 run-command.c:950 child_exit[0] pid:-1 code:-1 elapsed:0.000246 15:57:42.275763 git.c:389 alias ig -> check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:57:42.275781 git.c:753 cmd_name _run_git_alias_ (_run_dashed_/_run_git_alias_) 15:57:42.275794 run-command.c:735 child_start[1] git check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:57:42.282613 common-main.c:48 version 2.26.2 15:57:42.282876 common-main.c:49 start /usr/local/Cellar/git/2.26.2/libexec/git-core/git check-ignore --verbose Makefile myprog myprog.amd64-darwin myprog.cm myprog.sml tmp 15:57:42.283146 repository.c:130 worktree /Users/Knoble/write/junk-drawer 15:57:42.283520 git.c:440 cmd_name check-ignore (_run_dashed_/_run_git_alias_/check-ignore) code/sml-binary/.gitignore:1:myprog myprog code/sml-binary/.gitignore:2:myprog.amd64-darwin myprog.amd64-darwin 15:57:42.284561 git.c:674 exit elapsed:0.003839 code:0 15:57:42.284588 trace2/tr2_tgt_normal.c:123 atexit elapsed:0.003876 code:0 15:57:42.285171 run-command.c:990 child_exit[1] pid:99078 code:0 elapsed:0.009354 15:57:42.285212 git.c:773 exit elapsed:0.012930 code:0 15:57:42.285246 trace2/tr2_tgt_normal.c:123 atexit elapsed:0.012950 code:0

Failed attempt to produce a minimal example:

$ g init
Dépôt Git vide initialisé dans /private/tmp/git-test/.git/
$ mkdir subdir
$ touch subdir/{a..c}
$ ls
subdir/
$ tree
.
└── subdir
    ├── a
    ├── b
    └── c

1 directory, 3 files
$ echo a >> subdir/.gitignore
$ g status -s
?? subdir/
$ g add --intend-to-add .
$ g status -s
 A subdir/.gitignore
 A subdir/b
 A subdir/c
$ g commit --all -m 'init'
[master (commit racine) 832876e] init
 3 files changed, 1 insertion(+)
 create mode 100644 subdir/.gitignore
 create mode 100644 subdir/b
 create mode 100644 subdir/c
$ g igv *
$ echo $?
1
# ^^^ expected, nothing ignored
$ g igv subdir/*
subdir/.gitignore:1:a   subdir/a
# ^^^ also expected???

D. Ben Knoble

On 2020-05-10 15:59:08-0400, "D. Ben Knoble" <ben.knoble@gmail.com> wrote:

Your "git igv" is an alias to a shell command.

You're working on subdirectory of git worktree.

[.snip.]

In git-config(1), we've noted that:

           Note that
           shell commands will be executed from the top-level directory of a
           repository, which may not necessarily be the current directory.
           GIT_PREFIX is set as returned by running git rev-parse
           --show-prefix from the original current directory. See git-rev-
           parse(1).

Which is the parent directory of your "$PWD".

So, two below commands are equivalent:

	$ git igv sml-binary/*
	$ (cd .. && git check-ignore --verbose sml-binary/myprog sml-binary/myprog.amd64-darwin <and other files>)

From Git 2.23.0, Git allows recursive alias expansion:

	igv = ig --verbose