feat(usv2): set default balances on pool creation

substreams/ethereum-uniswap-v2/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ethereum-uniswap-v2"
-version = "0.3.0"
+version = "0.3.1"
 edition = "2021"
 
 [lib]

substreams/ethereum-uniswap-v2/src/modules/1_map_pool_created.rs

@@ -58,7 +58,7 @@ fn get_pools(block: &eth::Block, new_pools: &mut Vec<TransactionChanges>, params
             }],
             component_changes: vec![ProtocolComponent {
                 id: event.pair.to_hex(),
-                tokens: vec![event.token0, event.token1],
+                tokens: vec![event.token0.clone(), event.token1.clone()],
                 contracts: vec![],
                 static_att: vec![
                     // Trading Fee is hardcoded to 0.3%, saved as int in bps (basis points)
@@ -69,7 +69,7 @@ fn get_pools(block: &eth::Block, new_pools: &mut Vec<TransactionChanges>, params
                     },
                     Attribute {
                         name: "pool_address".to_string(),
-                        value: event.pair,
+                        value: event.pair.clone(),
                         change: ChangeType::Creation.into(),
                     },
                 ],
@@ -82,7 +82,18 @@ fn get_pools(block: &eth::Block, new_pools: &mut Vec<TransactionChanges>, params
                 }),
                 tx: Some(tycho_tx),
             }],
-            balance_changes: vec![],
+            balance_changes: vec![
+                BalanceChange {
+                    token: event.token0,
+                    balance: BigInt::from(0).to_signed_bytes_be(),
+                    component_id: event.pair.clone(),
+                },
+                BalanceChange {
+                    token: event.token1,
+                    balance: BigInt::from(0).to_signed_bytes_be(),
+                    component_id: event.pair,
+                },
+            ],
         })
     };