Forge a confirmed root before halting for RPC inspection (#10061)

(cherry picked from commit 1da1667)

# Conflicts:
#	core/src/commitment.rs

core/src/commitment.rs

@@ -163,6 +163,26 @@ impl BlockCommitmentCache {
  }
 
  #[cfg(test)]
+<<<<<<< HEAD
+=======
+ pub fn new_for_tests_with_blockstore_bank(
+ blockstore: Arc<Blockstore>,
+ bank: Arc<Bank>,
+ root: Slot,
+ ) -> Self {
+ let mut block_commitment: HashMap<Slot, BlockCommitment> = HashMap::new();
+ block_commitment.insert(0, BlockCommitment::default());
+ Self {
+ block_commitment,
+ blockstore,
+ total_stake: 42,
+ largest_confirmed_root: root,
+ bank,
+ root,
+ }
+ }
+
+>>>>>>> 1da166792... Forge a confirmed root before halting for RPC inspection (#10061)
  pub(crate) fn set_get_largest_confirmed_root(&mut self, root: Slot) {
  self.largest_confirmed_root = root;
  }

core/src/validator.rs

@@ -314,6 +314,13 @@ impl Validator {
  );
 
  if config.dev_halt_at_slot.is_some() {
+ // Simulate a confirmed root to avoid RPC errors with CommitmentmentConfig::max() and
+ // to ensure RPC endpoints like getConfirmedBlock, which require a confirmed root, work
+ block_commitment_cache
+ .write()
+ .unwrap()
+ .set_get_largest_confirmed_root(bank_forks.read().unwrap().root());
+
  // Park with the RPC service running, ready for inspection!
  warn!("Validator halted");
  std::thread::park();