Nested .gitignore breaks all ignores

[Cammisuli]

When using watchexec on a workspace that has folders with .gitignore files that contain * (which basically tells git to ignore this whole folder), it completely breaks ignores for the rest of the workspace.

You can clone this repro repo to see it in action:
https://github.com/Cammisuli/watch-exec-repro

Steps to reproduce:

1. clone repo

2. Open in vscode with rust analyzer (this just enables that files in the target/ directory is automatically changed)

3. run watchexec --project-origin=. -- echo '$WATCHEXEC_WRITTEN_PATH'

4. change src/main.rs (add a comment or whatever)

5. See output

   • the expected output should be just main.rs, but we get everything in target/ as well.

6. Stop the watchexec command

7. Delete this-should-ignore-children/.gitignore (or change the glob to something else)

8. run watchexec --project-origin=. -- echo '$WATCHEXEC_WRITTEN_PATH'

9. change src/main.rs

10. Output is only src/main.rs

• Watchexec's version

watchexec 1.22.2 (2023-03-22) 
build-date: 2023-03-22
release: 1.22.2
features: 

• The OS you're using

macOS 13.3.1 (22E261)

• A log with -vvvv --log-file
  watchexec.2023-05-02T18-19-42Z.log

I'll try and investigate this myself and post any findings.

[Cammisuli]

It looks like the GitIgnoreBuilder needs to be created for each ignore file.

watchexec/crates/filterer/globset/src/lib.rs

Line 61 in bccc029

let mut ignores_builder = GitignoreBuilder::new(origin);

Probably something needs to be done here instead:

watchexec/crates/ignore-files/src/filter.rs

Line 78 in bccc029

let mut builder = GitignoreBuilder::new(origin);

[passcod]

Yep, this (bug and reason for it) is known, and the next priority. However, I don't have time at the moment to work on it.

[Cammisuli]

I don't mind working on this if you don't have time.

If you have notes you want to share, or other pointers, I can begin fixing this.

[passcod]

Ultimately I want to replace all ignore handling, but a good start is probably to fix this particular issue, which is to use ignore properly, that is to make a gitignore instance per ignore file, and rewrite the ignore-files crate to handle both the building of that structure and the querying upon filtering. Likely a trie would be the ideal way to go but a vec or standard tree would probably work to start.

(My current understanding is that a gitignorebuilder is for a single directory; I believe that if two files apply to a single directory they can be handled by one builder. However that might be too much complexity for too little gain.)