Reverse range in character class

[staticssleever668]

Description

Sometimes when I open files with some characters in a directory's name in file path, vim-rooter prints an error.
The problem seems to be related to these symbols: -, [, ] and character u.

Steps to reproduce

folder_name="[u-a]" && mkdir -p "$folder_name" && touch "$folder_name/dummy" && vim "$folder_name/dummy"
Other folder names that trigger this error: [Au-S], [Audio-Stuff].

Full error message:

Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
E944: Reverse range in character class
Press ENTER or type command to continue
Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
Press ENTER or type command to continue
Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
Press ENTER or type command to continue
Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
Press ENTER or type command to continue
Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
Press ENTER or type command to continue
Error detected while processing function <SNR>35_rooter[5]..<SNR>35_root[11]..<SNR>35_match[8]..<SNR>35_has:
line    1:
E944: Reverse range in character class
Press ENTER or type command to continue```

[airblade]

Thank you for the clear bug report along with steps to reproduce :)

The "Reverse range in character class" error means that Vim is treating the folder name as a regexp; and [u-a] looks like a character class except backwards – i.e. if it's a regexp it should be [a-u].

:echo 's' =~ '[r-t]'     " => 1
:echo 's' =~ '[t-r]'     " => E944: Reverse range in character class

Of course the code should be treating the name as a literal, not a regexp. I'll fix it up.

[airblade]

The underlying problem is that when Rooter searches for "has" patterns, which are the most common, it uses globpath(). This concatenates the directory it's currently testing and the rooter pattern (e.g. .git), then expands the result with glob(). glob() expands the wildcards ?, *, **, and [abc] (character classes) – see :help wildcards.

So the problem is that even if your rooter patterns don't contain any wildcards, if you use "has" patterns and any of your files' ancestor directories contain wildcards, you'll get this undesired behaviour.

I had hoped that only the rooter pattern would be treated as a glob, not the directory too.

[airblade]

Does this patch solve the problem for you?

diff --git i/plugin/rooter.vim w/plugin/rooter.vim
index 4573cbd..55b6b18 100644
--- i/plugin/rooter.vim
+++ w/plugin/rooter.vim
@@ -166,7 +166,7 @@ endfunction
 " dir        - full path to a directory
 " identifier - a file name or a directory name; may be a glob
 function! s:has(dir, identifier)
-  return !empty(globpath(a:dir, a:identifier, 1))
+  return !empty(globpath(escape(a:dir, '?*[]'), a:identifier, 1))
 endfunction

[airblade]

Thanks for confirming.