better type_id for nested storages

crates/librqbit/src/session.rs

@@ -99,7 +99,9 @@ impl SessionDatabase {
                 .iter()
                 // We don't support serializing / deserializing of other storage types.
                 .filter(|(_, torrent)| {
-                    torrent.storage_factory.type_id() == TypeId::of::<FilesystemStorageFactory>()
+                    torrent
+                        .storage_factory
+                        .is_type_id(TypeId::of::<FilesystemStorageFactory>())
                 })
                 .map(|(id, torrent)| {
                     (

crates/librqbit/src/storage/mod.rs

@@ -4,7 +4,10 @@ pub mod mmap;
 pub mod slow;
 pub mod timing;
 
-use std::{any::Any, path::Path};
+use std::{
+    any::{Any, TypeId},
+    path::Path,
+};
 
 use crate::torrent_state::ManagedTorrentInfo;
 
@@ -12,6 +15,9 @@ pub trait StorageFactory: Send + Sync + Any {
     type Storage: TorrentStorage;
 
     fn init_storage(&self, info: &ManagedTorrentInfo) -> anyhow::Result<Self::Storage>;
+    fn is_type_id(&self, type_id: TypeId) -> bool {
+        Self::type_id(self) == type_id
+    }
 }
 
 pub type BoxStorageFactory = Box<dyn StorageFactory<Storage = Box<dyn TorrentStorage>>>;
@@ -33,6 +39,10 @@ impl<SF: StorageFactory> StorageFactoryExt for SF {
                 let s = self.sf.init_storage(info)?;
                 Ok(Box::new(s))
             }
+
+            fn is_type_id(&self, type_id: TypeId) -> bool {
+                self.sf.type_id() == type_id
+            }
         }
 
         Box::new(Wrapper { sf: self })

crates/librqbit/src/storage/slow.rs

@@ -24,6 +24,10 @@ impl<U: StorageFactory> StorageFactory for SlowStorageFactory<U> {
             underlying: self.underlying_factory.init_storage(info)?,
         })
     }
+
+    fn is_type_id(&self, type_id: std::any::TypeId) -> bool {
+        self.underlying_factory.is_type_id(type_id)
+    }
 }
 
 pub struct SlowStorage<U> {

crates/librqbit/src/storage/timing.rs

@@ -23,6 +23,10 @@ impl<U: StorageFactory> StorageFactory for TimingStorageFactory<U> {
             underlying: self.underlying_factory.init_storage(info)?,
         })
     }
+
+    fn is_type_id(&self, type_id: std::any::TypeId) -> bool {
+        self.underlying_factory.is_type_id(type_id)
+    }
 }
 
 pub struct TimingStorage<U> {