Ignoring of subdirectories is inconsistent with git

[dmit]

I have an entry target/ in .gitignore to ignore all target directories in the project. ag handles it fine and ignores all matching directories. rg only ignores the matching top level directory. If I change the pattern to **/target/ then rg works as expected, but ag stops ignoring all target directories. In both cases git ignores both the top level directory and the subdirectories.

Here's a shell session to illustrate the issue:

/p/tmp> rg --version
0.1.16
/p/tmp> git init abc
Initialized empty Git repository in /private/tmp/abc/.git/
/p/tmp> cd abc/
/p/t/abc> mkdir ghi
/p/t/abc> mkdir -p def/ghi
/p/t/abc> echo ghi/ > .gitignore
/p/t/abc> echo xyz > ghi/toplevel.txt
/p/t/abc> echo xyz > def/ghi/subdir.txt
/p/t/abc> ag xyz
/p/t/abc> rg xyz
def/ghi/subdir.txt
1:xyz
/p/t/abc> git status
On branch master

Initial commit

Untracked files:
  (use "git add <file>..." to include in what will be committed)

        .gitignore

nothing added to commit but untracked files present (use "git add" to track)
/p/t/abc> echo '**/ghi/' > .gitignore
/p/t/abc> ag xyz
def/ghi/subdir.txt
1:xyz

ghi/toplevel.txt
1:xyz
/p/t/abc> rg xyz
No files were searched, which means ripgrep probably applied a filter you didn't expect. Try running again with --debug.
/p/t/abc> git status
On branch master

Initial commit

Untracked files:
  (use "git add <file>..." to include in what will be committed)

        .gitignore

nothing added to commit but untracked files present (use "git add" to track)

DEBUG:rg::ignore: ./ghi ignored by Pattern { from: "./.gitignore", original: "ghi/", pat: "ghi", whitelist: false, only_dir: true }

[BurntSushi]

Confirmed. This one is embarrassing.

[BurntSushi]

The specific problem here was a bug translating the .gitignore path into a glob with the right semantics defined by gitignore. Specifically, it was being treated as an absolute path, which of course, it's not (because it lacks the leading /).