From ea6b7dd96bc1f30b87c1a41cc08281f11615d66c Mon Sep 17 00:00:00 2001
From: Joe <jcaulfield135@gmail.com>
Date: Wed, 16 Aug 2023 21:23:06 -0600
Subject: [PATCH] remove non-data swap

---
 runtime/src/bank.rs       | 18 +++---------------
 runtime/src/bank/tests.rs | 36 +++++++++++++++++++++---------------
 2 files changed, 24 insertions(+), 30 deletions(-)

diff --git a/runtime/src/bank.rs b/runtime/src/bank.rs
index 568653c491dabc..c89b4c2e99b074 100644
--- a/runtime/src/bank.rs
+++ b/runtime/src/bank.rs
@@ -8191,22 +8191,10 @@ impl Bank {
                     self.capitalization
                         .fetch_sub(new_account.lamports(), Relaxed);
                     self.store_account(new_address, &AccountSharedData::default());
-                } else if let Some(old_data_account) =
-                    self.get_account_with_fixed_root(&old_data_address)
+                } else if self
+                    .get_account_with_fixed_root(&old_data_address)
+                    .is_none()
                 {
-                    // A data account exists for the old program, but not the
-                    // new program
-                    // Swap program accounts and delete the old data account
-                    self.replace_account(
-                        old_address,
-                        new_address,
-                        Some(&old_account),
-                        &new_account,
-                    );
-                    self.capitalization
-                        .fetch_sub(old_data_account.lamports(), Relaxed);
-                    self.store_account(&old_data_address, &AccountSharedData::default());
-                } else {
                     // A data account does not exist for the new program
                     // Swap program accounts only
                     self.replace_account(
diff --git a/runtime/src/bank/tests.rs b/runtime/src/bank/tests.rs
index 9ec80c46054beb..4ad4355960101e 100644
--- a/runtime/src/bank/tests.rs
+++ b/runtime/src/bank/tests.rs
@@ -8173,15 +8173,17 @@ fn test_upgradable_program_replace_with_no_data() {
     // - OldData: [Old program data]
     // - New:     [*New program data]
     //
-    // Should replace the program account and delete the data account:
-    // - Old:     [*New program data]
+    // This is NOT allowed and should leave the program unchanged:
+    // - Old:     PDA(OldData)
+    // - OldData: [Old program data]
     let bpf_id = bpf_loader_upgradeable::id();
     let mut bank = create_simple_test_bank(0);
 
     let old = Pubkey::new_unique();
     let (old_data, _) = Pubkey::find_program_address(&[old.as_ref()], &bpf_id);
+    let old_program_bytes = vec![0, 1, 2, 3, 4, 5, 6];
     set_up_account_with_bank(&mut bank, &old, 100, old_data.to_bytes().to_vec());
-    set_up_account_with_bank(&mut bank, &old_data, 102, vec![0, 1, 2, 3, 4, 5, 6]);
+    set_up_account_with_bank(&mut bank, &old_data, 102, old_program_bytes.clone());
 
     let new = Pubkey::new_unique();
     let new_program_bytes = vec![6, 5, 4, 3, 2, 1, 0];
@@ -8191,22 +8193,26 @@ fn test_upgradable_program_replace_with_no_data() {
 
     bank.replace_program_account(&old, &new, "bank-apply_program_replacement");
 
-    // Old program account balance is unchanged
+    // All balances are unchanged
     assert_eq!(bank.get_balance(&old), 100);
+    assert_eq!(bank.get_balance(&old_data), 102);
+    assert_eq!(bank.get_balance(&new), 100);
 
-    // Old data account is now empty
-    assert_eq!(bank.get_balance(&old_data), 0);
-
-    // New program account is now empty
-    assert_eq!(bank.get_balance(&new), 0);
-
-    // Old program account now holds the new program bytes
-    // - Old:     [*New program data]
+    // Old program accounts' data are unchanged
+    // - Old:     PDA(OldData)
+    // - OldData: [Old program data]
     let old_account = bank.get_account(&old).unwrap();
-    assert_eq!(old_account.data(), &new_program_bytes,);
+    assert_eq!(old_account.data(), &old_data.to_bytes().to_vec());
+    let old_data_account = bank.get_account(&old_data).unwrap();
+    assert_eq!(old_data_account.data(), &old_program_bytes);
 
-    // Lamports in the old token accounts were burnt
-    assert_eq!(bank.capitalization(), original_capitalization - 100 - 102);
+    // New program account is unchanged
+    // - New:     [*New program data]
+    let new_account = bank.get_account(&new).unwrap();
+    assert_eq!(new_account.data(), &new_program_bytes);
+
+    // Lamports were unchanged across the board
+    assert_eq!(bank.capitalization(), original_capitalization);
 }
 
 fn min_rent_exempt_balance_for_sysvars(bank: &Bank, sysvar_ids: &[Pubkey]) -> u64 {