Print warnings when fetching pending blocks

ethcore/src/miner/miner.rs

@@ -290,10 +290,12 @@ impl Miner {
  {
  self.sealing.lock().queue
  .peek_last_ref()
- .and_then(|b| if b.block().header().number() > latest_block_number {
- Some(f(b))
- } else {
- None
+ .and_then(|b| {
+ if b.block().header().number() > latest_block_number {
+ Some(f(b))
+ } else {
+ None
+ }
  })
  }
 

rpc/src/v1/impls/eth.rs

@@ -108,6 +108,7 @@ pub struct EthClient<C, SN: ?Sized, S: ?Sized, M, EM> where
  eip86_transition: u64,
 }
 
+#[derive(Debug)]
 enum BlockNumberOrId {
  Number(BlockNumber),
  Id(BlockId),
@@ -184,29 +185,38 @@ impl<C, SN: ?Sized, S: ?Sized, M, EM, T: StateInfo + 'static> EthClient<C, SN, S
  let (block, difficulty, extra, is_pending) = match id {
  BlockNumberOrId::Number(BlockNumber::Pending) => {
  let info = self.client.chain_info();
- let pending_block = self.miner.pending_block(info.best_block_number);
- let difficulty = {
- let latest_difficulty = self.client.block_total_difficulty(BlockId::Latest).expect("blocks in chain have details; qed");
- let pending_difficulty = self.miner.pending_block_header(info.best_block_number).map(|header| *header.difficulty());
+ match self.miner.pending_block(info.best_block_number) {
+ Some(pending_block) => {
+ warn!("`Pending` is deprecated and may be removed in future versions.");
 
- if let Some(difficulty) = pending_difficulty {
- difficulty + latest_difficulty
- } else {
- latest_difficulty
- }
- };
+ let difficulty = {
+ let latest_difficulty = self.client.block_total_difficulty(BlockId::Latest).expect("blocks in chain have details; qed");
+ let pending_difficulty = self.miner.pending_block_header(info.best_block_number).map(|header| *header.difficulty());
+
+ if let Some(difficulty) = pending_difficulty {
+ difficulty + latest_difficulty
+ } else {
+ latest_difficulty
+ }
+ };
 
- let extra = pending_block.as_ref().map(|b| self.client.engine().extra_info(&b.header));
+  let extra = self.client.engine().extra_info(&pending_block.header);
 
- (pending_block.map(|b| encoded::Block::new(b.rlp_bytes())), Some(difficulty), extra, true)
+ (Some(encoded::Block::new(pending_block.rlp_bytes())), Some(difficulty), Some(extra), true)
+ },
+ None => {
+ warn!("`Pending` is deprecated and may be removed in future versions. Falling back to `Latest`");
+ client_query(BlockId::Latest)
+ }
+ }
  },
 
  BlockNumberOrId::Number(num) => {
  let id = match num {
  BlockNumber::Latest => BlockId::Latest,
  BlockNumber::Earliest => BlockId::Earliest,
  BlockNumber::Num(n) => BlockId::Number(n),
- BlockNumber::Pending => unreachable!(), // Already covered
+ BlockNumber::Pending => unreachable!() // Already covered
  };
 
  client_query(id)