1 files changed, 25 insertions, 4 deletions
diff --git a/mingling_core/src/asset/chain/error.rs b/mingling_core/src/asset/chain/error.rs
index e5c753d..39e4f62 100644
--- a/mingling_core/src/asset/chain/error.rs
+++ b/mingling_core/src/asset/chain/error.rs
@@ -1,12 +1,33 @@
 use crate::error::ProgramInternalExecuteError;
 
-#[derive(thiserror::Error, Debug)]
+#[derive(Debug)]
 pub enum ChainProcessError {
-    #[error("Other error: {0}")]
     Other(String),
+    IO(std::io::Error),
+}
+
+impl std::fmt::Display for ChainProcessError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ChainProcessError::Other(s) => write!(f, "Other error: {}", s),
+            ChainProcessError::IO(e) => write!(f, "IO error: {}", e),
+        }
+    }
+}
 
-    #[error("IO error: {0}")]
-    IO(#[from] std::io::Error),
+impl std::error::Error for ChainProcessError {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            ChainProcessError::IO(e) => Some(e),
+            ChainProcessError::Other(_) => None,
+        }
+    }
+}
+
+impl From<std::io::Error> for ChainProcessError {
+    fn from(e: std::io::Error) -> Self {
+        ChainProcessError::IO(e)
+    }
 }
 
 impl From<ProgramInternalExecuteError> for ChainProcessError {