unique_repr, no default impl

ethstore/src/dir/disk.rs

@@ -225,7 +225,7 @@ impl<T> KeyDirectory for DiskDirectory<T> where T: KeyFileManager {
 		Some(self)
 	}
 
-	fn hash(&self) -> Result<u64, Error> { 
+	fn unique_repr(&self) -> Result<u64, Error> { 
 		self.files_hash() 
 	}
 }

ethstore/src/dir/geth.rs

@@ -95,4 +95,8 @@ impl KeyDirectory for GethDirectory {
 	fn remove(&self, account: &SafeAccount) -> Result<(), Error> {
 		self.dir.remove(account)
 	}
+
+	fn unique_repr(&self) -> Result<u64, Error> {
+		self.dir.unique_repr()
+	}
 }

ethstore/src/dir/memory.rs

@@ -63,5 +63,12 @@ impl KeyDirectory for MemoryDirectory {
 		}
 		Ok(())
 	}
+
+	fn unique_repr(&self) -> Result<u64, Error> {
+		let mut val = 0u64;
+		let accounts = self.accounts.read();
+		for acc in accounts.keys() { val = val ^ ::util::FixedHash::low_u64(acc) }
+		Ok(val)
+	}
 }
 

ethstore/src/dir/mod.rs

@@ -62,8 +62,8 @@ pub trait KeyDirectory: Send + Sync {
 	fn path(&self) -> Option<&PathBuf> { None }
 	/// Return vault provider, if available
 	fn as_vault_provider(&self) -> Option<&VaultKeyDirectoryProvider> { None }
-	/// Returns hash of the directory content, if supported
-	fn hash(&self) -> Result<u64, Error> { Ok(0u64) }
+	/// Unique representation of directory account collection
+	fn unique_repr(&self) -> Result<u64, Error>;
 }
 
 /// Vaults provider

ethstore/src/dir/parity.rs

@@ -74,4 +74,8 @@ impl KeyDirectory for ParityDirectory {
 	fn remove(&self, account: &SafeAccount) -> Result<(), Error> {
 		self.dir.remove(account)
 	}
+
+	fn unique_repr(&self) -> Result<u64, Error> {
+		self.dir.unique_repr()
+	}
 }

ethstore/src/ethstore.rs

@@ -253,7 +253,7 @@ impl EthMultiStore {
 
 	fn reload_if_changed(&self) -> Result<(), Error> {
 		let mut last_dir_hash = self.dir_hash.lock();
-		let dir_hash = Some(self.dir.hash()?);
+		let dir_hash = Some(self.dir.unique_repr()?);
 		if *last_dir_hash == dir_hash {
 			return Ok(())
 		}

ethstore/tests/util/transient_dir.rs

@@ -74,4 +74,8 @@ impl KeyDirectory for TransientDir {
 	fn remove(&self, account: &SafeAccount) -> Result<(), Error> {
 		self.dir.remove(account)
 	}
+
+	fn unique_repr(&self) -> Result<u64, Error> {
+		self.dir.unique_repr()
+	}
 }