feedback: rework rent check and test tx dedupe

Author: buffalojoec

token/client/src/token.rs

@@ -3876,19 +3876,23 @@ where
         &self,
     ) -> TokenResult<u64> {
         let account = self.get_account(self.pubkey).await?;
+        let account_data_len = account.data.len();
         let account_lamports = account.lamports;
-        let new_account_len = account
-            .data
-            .len()
-            .saturating_add(size_of::<ExtensionType>())
-            .saturating_add(size_of::<Length>())
-            .saturating_add(size_of::<V>());
-        let new_rent_exempt_minimum = self
-            .client
-            .get_minimum_balance_for_rent_exemption(new_account_len)
-            .await
-            .map_err(TokenError::Client)?;
-        Ok(new_rent_exempt_minimum.saturating_sub(account_lamports))
+        let mint_state = self.unpack_mint_info(account)?;
+        if mint_state.get_extension::<V>().is_ok() {
+            Ok(0)
+        } else {
+            let new_account_len = account_data_len
+                .saturating_add(size_of::<ExtensionType>())
+                .saturating_add(size_of::<Length>())
+                .saturating_add(size_of::<V>());
+            let new_rent_exempt_minimum = self
+                .client
+                .get_minimum_balance_for_rent_exemption(new_account_len)
+                .await
+                .map_err(TokenError::Client)?;
+            Ok(new_rent_exempt_minimum.saturating_sub(account_lamports))
+        }
     }
 
     /// Initialize token-group on a mint

token/program-2022-test/tests/program_test.rs

@@ -146,7 +146,7 @@ impl TestContext {
         let token_unchecked = Token::new_native(Arc::clone(&client), &id(), Arc::new(payer));
         self.token_context = Some(TokenContext {
             decimals: native_mint::DECIMALS,
-            mint_authority: Keypair::new(), /*bogus*/
+            mint_authority: Keypair::new(), /* bogus */
             token,
             token_unchecked,
             alice: Keypair::new(),

token/program-2022-test/tests/token_group_initialize.rs

@@ -131,7 +131,7 @@ async fn success_initialize() {
             &payer_pubkey,
             &token_context.mint_authority.pubkey(),
             &update_authority,
-            max_size,
+            12, // Change so we get a different transaction
             &[&token_context.mint_authority],
         )
         .await
@@ -140,7 +140,7 @@ async fn success_initialize() {
         error,
         TokenClientError::Client(Box::new(TransportError::TransactionError(
             TransactionError::InstructionError(
-                1,
+                0, // No additional rent
                 InstructionError::Custom(TokenError::ExtensionAlreadyInitialized as u32)
             )
         )))