globset: permit ** to appear anywhere

Previously, `man gitignore` specified that `**` was invalid unless it
was used in one of a few specific circumstances, i.e., `**`, `a/**`,
`**/b` or `a/**/b`. That is, `**` always had to be surrounded by either
a path separator or the beginning/end of the pattern.

It turns out that git itself has treated `**` outside the above contexts
as valid for quite a while, so there was an inconsistency between the
spec `man gitignore` and the implementation, and it wasn't clear which
was actually correct.

@okdana filed a bug against git[1] and got this fixed. The spec was wrong,
which has now been fixed [2] and updated[2].

This commit brings ripgrep in line with git and treats `**` outside of
the above contexts as two consecutive `*` patterns. We deprecate the
`InvalidRecursive` error since it is no longer used.

Fixes #373, Fixes #1098

[1] - https://public-inbox.org/git/C16A9F17-0375-42F9-90A9-A92C9F3D8BBA@dana.is
[2] - https://github.com/git/git/commit/627186d0206dcb219c43f8e6670b4487802a4921
[3] - https://git-scm.com/docs/gitignore

1 files changed, 5 insertions, 5 deletions

diff --git a/ignore/src/dir.rs b/ignore/src/dir.rs
index 30f4cb87..3ba0ede8 100644
--- a/ignore/src/dir.rs
+++ b/ignore/src/dir.rs
@@ -869,7 +869,7 @@ mod tests {
     #[test]
     fn errored() {
         let td = tmpdir("ignore-test-");
-        wfile(td.path().join(".gitignore"), "f**oo");
+        wfile(td.path().join(".gitignore"), "{foo");
 
         let (_, err) = IgnoreBuilder::new().build().add_child(td.path());
         assert!(err.is_some());
@@ -878,8 +878,8 @@ mod tests {
     #[test]
     fn errored_both() {
         let td = tmpdir("ignore-test-");
-        wfile(td.path().join(".gitignore"), "f**oo");
-        wfile(td.path().join(".ignore"), "fo**o");
+        wfile(td.path().join(".gitignore"), "{foo");
+        wfile(td.path().join(".ignore"), "{bar");
 
         let (_, err) = IgnoreBuilder::new().build().add_child(td.path());
         assert_eq!(2, partial(err.expect("an error")).len());
@@ -889,7 +889,7 @@ mod tests {
     fn errored_partial() {
         let td = tmpdir("ignore-test-");
         mkdirp(td.path().join(".git"));
-        wfile(td.path().join(".gitignore"), "f**oo\nbar");
+        wfile(td.path().join(".gitignore"), "{foo\nbar");
 
         let (ig, err) = IgnoreBuilder::new().build().add_child(td.path());
         assert!(err.is_some());
@@ -899,7 +899,7 @@ mod tests {
     #[test]
     fn errored_partial_and_ignore() {
         let td = tmpdir("ignore-test-");
-        wfile(td.path().join(".gitignore"), "f**oo\nbar");
+        wfile(td.path().join(".gitignore"), "{foo\nbar");
         wfile(td.path().join(".ignore"), "!bar");
 
         let (ig, err) = IgnoreBuilder::new().build().add_child(td.path());