Removes Bank::replace_program_account() (#9396)

Author: brooksprumo

runtime/src/bank.rs

@@ -5696,43 +5696,6 @@ impl Bank {
         }
     }
 
-    /// Use to replace programs by feature activation
-    #[allow(dead_code)]
-    fn replace_program_account(
-        &mut self,
-        old_address: &Pubkey,
-        new_address: &Pubkey,
-        datapoint_name: &'static str,
-    ) {
-        if let Some(old_account) = self.get_account_with_fixed_root(old_address) {
-            if let Some(new_account) = self.get_account_with_fixed_root(new_address) {
-                datapoint_info!(datapoint_name, ("slot", self.slot, i64));
-
-                // Burn lamports in the old account
-                self.capitalization
-                    .fetch_sub(old_account.lamports(), Relaxed);
-
-                // Transfer new account to old account
-                self.store_account(old_address, &new_account);
-
-                // Clear new account
-                self.store_account(new_address, &AccountSharedData::default());
-
-                // Unload a program from the bank's cache
-                self.transaction_processor
-                    .global_program_cache
-                    .write()
-                    .unwrap()
-                    .remove_programs([*old_address].into_iter());
-
-                self.calculate_and_update_accounts_data_size_delta_off_chain(
-                    old_account.data().len(),
-                    new_account.data().len(),
-                );
-            }
-        }
-    }
-
     /// Calculates the accounts data size of all accounts
     ///
     /// Panics if total overflows a u64.

runtime/src/bank/tests.rs

@@ -7031,44 +7031,6 @@ fn test_block_limits() {
     );
 }
 
-#[test]
-fn test_program_replacement() {
-    let mut bank = create_simple_test_bank(0);
-
-    // Setup original program account
-    let old_address = Pubkey::new_unique();
-    let new_address = Pubkey::new_unique();
-    bank.store_account_and_update_capitalization(
-        &old_address,
-        &AccountSharedData::from(Account {
-            lamports: 100,
-            ..Account::default()
-        }),
-    );
-    assert_eq!(bank.get_balance(&old_address), 100);
-
-    // Setup new program account
-    let new_program_account = AccountSharedData::from(Account {
-        lamports: 123,
-        ..Account::default()
-    });
-    bank.store_account_and_update_capitalization(&new_address, &new_program_account);
-    assert_eq!(bank.get_balance(&new_address), 123);
-
-    let original_capitalization = bank.capitalization();
-
-    bank.replace_program_account(&old_address, &new_address, "bank-apply_program_replacement");
-
-    // New program account is now empty
-    assert_eq!(bank.get_balance(&new_address), 0);
-
-    // Old program account holds the new program account
-    assert_eq!(bank.get_account(&old_address), Some(new_program_account));
-
-    // Lamports in the old token account were burnt
-    assert_eq!(bank.capitalization(), original_capitalization - 100);
-}
-
 fn min_rent_exempt_balance_for_sysvars(bank: &Bank, sysvar_ids: &[Pubkey]) -> u64 {
     sysvar_ids
         .iter()