Fixed recursion using a BoxFuture.

src/command/build/walk_fs.rs

@@ -1,14 +1,17 @@
 use std::ops::AsyncFn;
 use std::path::Path;
 
+use futures::future::BoxFuture;
+use futures::FutureExt;
 use tokio::fs::DirEntry;
 
 use crate::error::CustomError;
 
-pub(crate) async fn walk_fs<P: AsRef<Path>>(
+pub(crate) fn walk_fs<P: AsRef<Path> + std::marker::Send + 'static>(
     root: P,
     predicate: fn(&DirEntry) -> Result<bool, CustomError>,
-) -> Result<Vec<DirEntry>, CustomError> {
+) -> BoxFuture<'static, Result<Vec<DirEntry>, CustomError>> {
+    async move {
         let mut ret = Vec::new();
         let mut entries = tokio::fs::read_dir(root).await?;
         while let Some(entry) = entries.next_entry().await? {
@@ -24,3 +27,5 @@ pub(crate) async fn walk_fs<P: AsRef<Path>>(
 
         Ok(ret)
     }
+    .boxed()
+}