the doc of stat in Accessor trait looks not consistent with source code

[drivebyer]

Hi,
In the Accessor trait

    /// Invoke the `stat` operation on the specified path.
    ///
    /// ## Behavior
    ///
    /// - `Stat` empty path means stat backend's root path.
    /// - `Stat` a path endswith "/" means stating a dir.
    ///   - On fs, an error could return if not a dir.
    ///   - On s3 alike backends, a dir object will return no matter it exist or not.
    async fn stat(&self, args: &OpStat) -> Result<Metadata> {
        let _ = args;
        unimplemented!()
    }

the doc isfs, an error could return if not a dir , but related implementation is

        if meta.is_dir() {
            m.set_mode(ObjectMode::DIR);   
        } else {
            // TODO: we should handle LINK or other types here.
            m.set_mode(ObjectMode::FILE);   // here, no error 
        }

BTW, why the stat should return error when stat a fs dir?

[Xuanwo]

Thanks for pointing out, it's indeed a bug. We used to not support dir but the design has been changed. We will fix those inconsistent while implementing full dir support: #185