program-test: Remove special case for Rent sysvar (bp #13434) (#13435)

* Revert "Include Rent in ProgramTest::start() output"

This reverts commit c3d2d2134c.

(cherry picked from commit 920cd5285a)

* Add get_rent()

(cherry picked from commit 9a1c1fbab8)

Co-authored-by: Michael Vines <mvines@gmail.com>

banks-client/src/lib.rs

@@ -10,9 +10,17 @@ use futures::future::join_all;
 pub use solana_banks_interface::{BanksClient, TransactionStatus};
 use solana_banks_interface::{BanksRequest, BanksResponse};
 use solana_sdk::{
-    account::Account, clock::Slot, commitment_config::CommitmentLevel,
-    fee_calculator::FeeCalculator, hash::Hash, pubkey::Pubkey, signature::Signature,
-    transaction::Transaction, transport,
+    account::{from_account, Account},
+    clock::Slot,
+    commitment_config::CommitmentLevel,
+    fee_calculator::FeeCalculator,
+    hash::Hash,
+    pubkey::Pubkey,
+    rent::Rent,
+    signature::Signature,
+    sysvar,
+    transaction::Transaction,
+    transport,
 };
 use std::io::{self, Error, ErrorKind};
 use tarpc::{
@@ -40,6 +48,9 @@ pub trait BanksClientExt {
     /// use them to calculate the transaction fee.
     async fn get_fees(&mut self) -> io::Result<(FeeCalculator, Hash, Slot)>;
 
+    /// Return the cluster rent
+    async fn get_rent(&mut self) -> io::Result<Rent>;
+
     /// Send a transaction and return after the transaction has been rejected or
     /// reached the given level of commitment.
     async fn process_transaction_with_commitment(
@@ -108,6 +119,17 @@ impl BanksClientExt for BanksClient {
             .await
     }
 
+    async fn get_rent(&mut self) -> io::Result<Rent> {
+        let rent_sysvar = self
+            .get_account(sysvar::rent::id())
+            .await?
+            .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "Rent sysvar not present"))?;
+
+        from_account::<Rent>(&rent_sysvar).ok_or_else(|| {
+            io::Error::new(io::ErrorKind::Other, "Failed to deserialize Rent sysvar")
+        })
+    }
+
     async fn get_recent_blockhash(&mut self) -> io::Result<Hash> {
         Ok(self.get_fees().await?.1)
     }

program-test/src/lib.rs

@@ -395,14 +395,6 @@ impl Default for ProgramTest {
     }
 }
 
-// Values returned by `ProgramTest::start`
-pub struct StartOutputs {
-    pub banks_client: BanksClient,
-    pub payer: Keypair,
-    pub recent_blockhash: Hash,
-    pub rent: Rent,
-}
-
 impl ProgramTest {
     pub fn new(
         program_name: &str,
@@ -552,7 +544,7 @@ impl ProgramTest {
     ///
     /// Returns a `BanksClient` interface into the test environment as well as a payer `Keypair`
     /// with SOL for sending transactions
-    pub async fn start(self) -> StartOutputs {
+    pub async fn start(self) -> (BanksClient, Keypair, Hash) {
         {
             use std::sync::Once;
             static ONCE: Once = Once::new();
@@ -571,8 +563,7 @@ impl ProgramTest {
             bootstrap_validator_stake_lamports,
         );
         let mut genesis_config = gci.genesis_config;
-        let rent = Rent::default();
-        genesis_config.rent = rent;
+        genesis_config.rent = Rent::default();
         genesis_config.fee_rate_governor =
             solana_program::fee_calculator::FeeRateGovernor::default();
         let payer = gci.mint_keypair;
@@ -624,11 +615,6 @@ impl ProgramTest {
             .unwrap_or_else(|err| panic!("Failed to start banks client: {}", err));
 
         let recent_blockhash = banks_client.get_recent_blockhash().await.unwrap();
-        StartOutputs {
-            banks_client,
-            payer,
-            recent_blockhash,
-            rent,
-        }
+        (banks_client, payer, recent_blockhash)
     }
 }