Do not lose error

drink/src/errors.rs

@@ -3,7 +3,7 @@
 use thiserror::Error;
 
 /// Main error type for the drink crate.
-#[derive(Error, Debug)]
+#[derive(Clone, Error, Debug)]
 pub enum Error {
     /// Externalities could not be initialized.
     #[error("Failed to build storage: {0}")]

drink/src/session.rs

@@ -470,13 +470,13 @@ where
         message: &str,
         args: &[S],
         endowment: Option<BalanceOf<T::Runtime>>,
-    ) -> E {
-        self.call_internal::<_, Result<(), E>>(None, message, args, endowment)
+    ) -> Result<E, SessionError> {
+        Ok(self
+            .call_internal::<_, Result<(), E>>(None, message, args, endowment)
             .expect_err("Call should fail")
-            .decode_revert::<Result<(), E>>()
-            .expect("Call should be reverted")
+            .decode_revert::<Result<(), E>>()?
             .expect("Call should return an error")
-            .expect_err("Call should return an error")
+            .expect_err("Call should return an error"))
     }
 
     /// Calls a contract with a given address. In case of a successful call, returns the encoded

drink/src/session/error.rs

@@ -7,7 +7,7 @@ use thiserror::Error;
 use crate::errors::MessageResult;
 
 /// Session specific errors.
-#[derive(Error, Debug)]
+#[derive(Clone, Error, Debug)]
 pub enum SessionError {
     /// Encoding data failed.
     #[error("Encoding call data failed: {0}")]
@@ -43,12 +43,12 @@ pub enum SessionError {
 
 impl SessionError {
     /// Check if the error is a revert error and if so, decode the error message.
-    pub fn decode_revert<T: Decode>(&self) -> Option<MessageResult<T>> {
+    pub fn decode_revert<T: Decode>(&self) -> Result<MessageResult<T>, Self> {
         match self {
             SessionError::CallReverted(error) => {
-                Some(MessageResult::decode(&mut &error[..]).expect("Failed to decode error"))
+                Ok(MessageResult::decode(&mut &error[..]).expect("Failed to decode error"))
             }
-            _ => None,
+            _ => Err(self.clone()),
         }
     }
 }