simulateTransaction can now return accounts modified by the simulation

client/src/blockhash_query.rs

@@ -361,7 +361,7 @@ mod tests {
         let nonce_pubkey = Pubkey::new(&[4u8; 32]);
         let rpc_nonce_account = UiAccount::encode(
             &nonce_pubkey,
-            nonce_account,
+            &nonce_account,
             UiAccountEncoding::Base64,
             None,
             None,

client/src/rpc_config.rs

@@ -23,6 +23,13 @@ pub struct RpcSendTransactionConfig {
     pub encoding: Option<UiTransactionEncoding>,
 }
 
+#[derive(Debug, Clone, Default, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct RpcSimulateTransactionAccountsConfig {
+    pub encoding: Option<UiAccountEncoding>,
+    pub addresses: Vec<String>,
+}
+
 #[derive(Debug, Default, Clone, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct RpcSimulateTransactionConfig {
@@ -33,6 +40,7 @@ pub struct RpcSimulateTransactionConfig {
     #[serde(flatten)]
     pub commitment: Option<CommitmentConfig>,
     pub encoding: Option<UiTransactionEncoding>,
+    pub accounts: Option<RpcSimulateTransactionAccountsConfig>,
 }
 
 #[derive(Debug, Default, Clone, PartialEq, Serialize, Deserialize)]

client/src/rpc_response.rs

@@ -318,6 +318,7 @@ pub struct RpcSignatureConfirmation {
 pub struct RpcSimulateTransactionResult {
     pub err: Option<TransactionError>,
     pub logs: Option<Vec<String>>,
+    pub accounts: Option<Vec<Option<UiAccount>>>,
 }
 
 #[derive(Serialize, Deserialize, Clone, Debug)]