add cg ls, prepare for rc subcommands

src/fs.rs

@@ -1,9 +1,38 @@
-use eyre::Result;
 use std::fs::Metadata;
-use std::path::PathBuf;
-use tokio::fs::read_dir;
+use std::path::{Path, PathBuf};
+use tokio::fs;
 use tokio::sync::mpsc;
 
+pub type Result<T> = std::result::Result<T, Error>;
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("{0}: read_dir: {1}")]
+    ReadDir(PathBuf, std::io::Error),
+    #[error("{0}: read: {1}")]
+    Read(PathBuf, std::io::Error),
+    #[error("{0}: stat: {1}")]
+    Stat(PathBuf, std::io::Error),
+    #[error("{0}: write: {1}")]
+    Write(PathBuf, std::io::Error),
+    #[error("{0}: {1}")]
+    Other(PathBuf, String),
+}
+
+macro_rules! wrap_path {
+    ($fn:ident $( ( $( $pname:ident : $ptype:ty ),* ) )? -> $result:ty, $err:ident) => {
+        pub async fn $fn(path: impl AsRef<Path>$($(, $pname: $ptype)*)?) -> Result<$result> {
+            let path = path.as_ref();
+            fs::$fn(path $($(, $pname)*)?).await.map_err(|e| Error::$err(path.into(), e))
+        }
+    };
+}
+
+wrap_path!(read_dir -> fs::ReadDir, ReadDir);
+wrap_path!(read -> Vec<u8>, Read);
+wrap_path!(read_to_string -> String, Read);
+wrap_path!(write(content: &[u8]) -> (), Write);
+
 pub fn spawn_walk_dir(
     dir: impl Into<PathBuf> + Send + 'static,
 ) -> mpsc::Receiver<Result<(PathBuf, Metadata)>> {
@@ -24,7 +53,7 @@ pub async fn walk_dir(dir: impl Into<PathBuf>, tx: mpsc::Sender<Result<(PathBuf,
         let entry = match rd.next_entry().await {
             Ok(v) => v,
             Err(e) => {
-                if tx.send(Err(e.into())).await.is_err() {
+                if tx.send(Err(Error::ReadDir(dir.clone(), e))).await.is_err() {
                     return;
                 }
                 todo.pop_front(); // skip dir on error