Merge pull request #60 from dforsten/hbbft-pending-contribution

Potential fix for 0-tx blocks.
I could confirm that this potential fix really solves the error.
#58

crates/ethcore/src/client/client.rs

@@ -3084,7 +3084,7 @@ impl super::traits::EngineClient for Client {
     }
 
     fn queued_transactions(&self) -> Vec<Arc<VerifiedTransaction>> {
-        self.importer.miner.queued_transactions()
+        self.importer.miner.queued_transactions(self)
     }
 
     fn create_pending_block_at(

crates/ethcore/src/client/test_client.rs

@@ -1173,7 +1173,7 @@ impl super::traits::EngineClient for TestBlockChainClient {
     }
 
     fn queued_transactions(&self) -> Vec<Arc<VerifiedTransaction>> {
-        self.miner.queued_transactions()
+        self.miner.queued_transactions(self)
     }
 
     fn create_pending_block_at(

crates/ethcore/src/engines/hbbft/test/hbbft_test_client.rs

@@ -116,7 +116,7 @@ impl HbbftTestClient {
     pub fn sync_transactions_to(&self, other: &mut Self) {
         let transactions = self
             .miner
-            .queued_transactions()
+            .all_transactions()
             //.transactions_to_propagate()
             .iter()
             .map(|i| i.signed().deref().clone())

crates/ethcore/src/miner/miner.rs

@@ -1072,6 +1072,11 @@ impl Miner {
             }
         }
     }
+
+    /// Return all transactions currently in the transaction queue.
+    pub fn all_transactions(&self) -> Vec<Arc<VerifiedTransaction>> {
+        self.transaction_queue.all_transactions()
+    }
 }
 
 const SEALING_TIMEOUT_IN_BLOCKS: u64 = 5;
@@ -1251,8 +1256,40 @@ impl miner::MinerService for Miner {
         self.transaction_queue.local_transactions()
     }
 
-    fn queued_transactions(&self) -> Vec<Arc<VerifiedTransaction>> {
-        self.transaction_queue.all_transactions()
+    fn queued_transactions<C>(&self, chain: &C) -> Vec<Arc<VerifiedTransaction>>
+    where
+        C: BlockChain + CallContract + Nonce + Sync,
+    {
+        let client = self.pool_client(chain);
+        let chain_info = chain.chain_info();
+        let min_tx_gas: U256 = self
+            .engine
+            .schedule(chain_info.best_block_number)
+            .tx_gas
+            .into();
+
+        let status = self.queue_status();
+
+        // we will never need more transactions than limit divided by min gas
+        let max_transactions = if min_tx_gas.is_zero() {
+            usize::MAX
+        } else {
+            MAX_SKIPPED_TRANSACTIONS.saturating_add(
+                cmp::min(status.options.block_gas_limit / min_tx_gas, u64::MAX.into()).as_u64()
+                    as usize,
+            )
+        };
+
+        self.transaction_queue.pending(
+            client.clone(),
+            pool::PendingSettings {
+                block_number: chain_info.best_block_number,
+                current_timestamp: chain_info.best_block_timestamp,
+                nonce_cap: None,
+                max_len: max_transactions,
+                ordering: miner::PendingOrdering::Priority,
+            },
+        )
     }
 
     fn queued_transaction_hashes(&self) -> Vec<H256> {

crates/ethcore/src/miner/mod.rs

@@ -243,7 +243,9 @@ pub trait MinerService: Send + Sync {
     }
 
     /// Get a list of all transactions in the pool (some of them might not be ready for inclusion yet).
-    fn queued_transactions(&self) -> Vec<Arc<VerifiedTransaction>>;
+    fn queued_transactions<C>(&self, chain: &C) -> Vec<Arc<VerifiedTransaction>>
+    where
+        C: BlockChain + CallContract + Nonce + Sync;
 
     /// Get a list of all transaction hashes in the pool (some of them might not be ready for inclusion yet).
     fn queued_transaction_hashes(&self) -> Vec<H256>;