# Filter parser

This workspace is dedicated to the parsing of the MeiliSearch filters.

Most of the code and explanation are in the [src/lib.rs]. Especially, the BNF of the filters at the top of this file.

The parser use [nom](https://docs.rs/nom/) to do most of its work and [nom-locate](https://docs.rs/nom_locate/) to keep track of what we were doing when we encountered an error.

## Cli
A simple main is provided to quick-test if a filter can be parsed or not without bringing milli.
It takes one argument and try to parse it.
```
cargo run -- 'field = value' # success
cargo run -- 'field = "doggo' # error => missing closing delimiter "
```

## Fuzz
The workspace have been fuzzed with [cargo-fuzz](https://rust-fuzz.github.io/book/cargo-fuzz.html).

### Setup
You'll need rust-nightly to execute the fuzzer.

```
cargo install cargo-fuzz
```

### Run
```
cargo fuzz run parse
```

## What to do if you find a bug in the parser

- Write a test at the end of the [src/lib.rs] to ensure it never happens again.
- Add a file in [fuzz/corpus/parse/] with your filter to help the fuzzer finding new bug.