chore: check both clarity tx and clarity db epoch versions at each epoch transition

Author: jcnelson

stackslib/src/chainstate/nakamoto/mod.rs

@@ -3937,7 +3937,11 @@ impl NakamotoChainState {
 
         // is this stacks block the first of a new epoch?
         let (applied_epoch_transition, mut tx_receipts) =
-            StacksChainState::process_epoch_transition(&mut clarity_tx, burn_header_height)?;
+            StacksChainState::process_epoch_transition(
+                &mut clarity_tx,
+                sortition_dbconn.as_burn_state_db(),
+                burn_header_height,
+            )?;
 
         debug!(
             "Setup block: Processed epoch transition";

stackslib/src/chainstate/stacks/db/blocks.rs

@@ -4044,6 +4044,7 @@ impl StacksChainState {
     /// Return (applied?, receipts)
     pub fn process_epoch_transition(
         clarity_tx: &mut ClarityTx,
+        burn_dbconn: &dyn BurnStateDB,
         chain_tip_burn_header_height: u32,
     ) -> Result<(bool, Vec<StacksTransactionReceipt>), Error> {
         // is this stacks block the first of a new epoch?
@@ -4111,6 +4112,22 @@ impl StacksChainState {
                         panic!("No defined transition from Epoch31 forward")
                     }
                 }
+
+                if current_epoch > StacksEpochId::Epoch2_05 {
+                    // clarity tx should now have the current epoch
+                    assert_eq!(
+                        clarity_tx.block.get_epoch(),
+                        current_epoch,
+                        "FATAL: clarity_tx does not have the current epoch"
+                    );
+
+                    // clarity DB should now have the current epoch
+                    assert_eq!(
+                        clarity_tx.block.get_clarity_db_epoch_version(burn_dbconn)?,
+                        current_epoch,
+                        "FATAL: clarity DB does not report the current epoch"
+                    );
+                }
             }
         }
 
@@ -5197,7 +5214,11 @@ impl StacksChainState {
 
         // is this stacks block the first of a new epoch?
         let (applied_epoch_transition, mut tx_receipts) =
-            StacksChainState::process_epoch_transition(&mut clarity_tx, burn_tip_height)?;
+            StacksChainState::process_epoch_transition(
+                &mut clarity_tx,
+                burn_dbconn,
+                burn_tip_height,
+            )?;
 
         debug!(
             "Setup block: Processed epoch transition at {}/{}",

stackslib/src/clarity_vm/clarity.rs

@@ -226,6 +226,21 @@ impl<'a, 'b> ClarityBlockConnection<'a, 'b> {
             None => None,
         }
     }
+
+    /// Load the epoch ID from the clarity DB.
+    /// Used to sanity-check epoch transitions.
+    pub fn get_clarity_db_epoch_version(
+        &mut self,
+        burn_state_db: &dyn BurnStateDB,
+    ) -> Result<StacksEpochId, Error> {
+        let mut db = self.datastore.as_clarity_db(self.header_db, burn_state_db);
+        // NOTE: the begin/roll_back shouldn't be necessary with how this gets used in practice,
+        // but is put here defensively.
+        db.begin();
+        let result = db.get_clarity_epoch_version();
+        db.roll_back()?;
+        Ok(result?)
+    }
 }
 
 impl ClarityInstance {