Merge pull request #31 from ElrondNetwork/feat/inter-pair-swap

Additional checks for swap in case of admin mistakes
multiversx · Apr 15, 2021 · ddcf545 · ddcf545
2 parents 0f3378f + ea79bec
commit ddcf545
Showing 1 changed file with 12 additions and 7 deletions.
diff --git a/elrond_dex_pair/src/lib.rs b/elrond_dex_pair/src/lib.rs
@@ -360,6 +360,7 @@ pub trait Pair {
         &self,
         #[payment_token] token_in: TokenIdentifier,
         #[payment] amount_in: BigUint,
+        token_out: TokenIdentifier,
         destination_address: Address,
     ) -> SCResult<()> {
         let caller = self.get_caller();
@@ -378,13 +379,16 @@ pub trait Pair {
 
         let first_token_id = self.liquidity_pool().first_token_id().get();
         let second_token_id = self.liquidity_pool().second_token_id().get();
-        let token_out = if token_in == first_token_id {
-            second_token_id.clone()
-        } else if token_in == second_token_id {
-            first_token_id.clone()
-        } else {
-            return sc_error!("Bad token input");
-        };
+        require!(token_in != token_out, "Cannot swap same token");
+        require!(
+            token_in == first_token_id || token_in == second_token_id,
+            "Invalid token in"
+        );
+        require!(
+            token_out == first_token_id || token_out == second_token_id,
+            "Invalid token out"
+        );
+
         let old_k = self.liquidity_pool().calculate_k_for_reserves();
 
         let amount_out = self.liquidity_pool().swap_safe_no_fee(
@@ -722,6 +726,7 @@ pub trait Pair {
         );
 
         let mut arg_buffer = ArgBuffer::new();
+        arg_buffer.push_argument_bytes(requested_token.as_esdt_identifier());
         arg_buffer.push_argument_bytes(destination_address.as_bytes());
         self.send().direct_esdt_execute(
             &pair_address,