Update release notes to include RPC error code changes.

Author: jnewbery

doc/release-notes.md

@@ -33,6 +33,55 @@ frequently tested on them.
 Notable changes
 ===============
 
+Low-level RPC changes
+---------------------
+
+- Error codes have been updated to be more accurate for the following error cases:
+  - `getblock` now returns RPC_MISC_ERROR if the block can't be found on disk (for
+  example if the block has been pruned). Previously returned RPC_INTERNAL_ERROR.
+  - `pruneblockchain` now returns RPC_MISC_ERROR if the blocks cannot be pruned
+  because the node is not in pruned mode. Previously returned RPC_METHOD_NOT_FOUND.
+  - `pruneblockchain` now returns RPC_INVALID_PARAMETER if the blocks cannot be pruned
+  because the supplied timestamp is too late. Previously returned RPC_INTERNAL_ERROR.
+  - `pruneblockchain` now returns RPC_MISC_ERROR if the blocks cannot be pruned
+  because the blockchain is too short. Previously returned RPC_INTERNAL_ERROR.
+  - `setban` now returns RPC_CLIENT_INVALID_IP_OR_SUBNET if the supplied IP address
+  or subnet is invalid. Previously returned RPC_CLIENT_NODE_ALREADY_ADDED.
+  - `setban` now returns RPC_CLIENT_INVALID_IP_OR_SUBNET if the user tries to unban
+  a node that has not previously been banned. Previously returned RPC_MISC_ERROR.
+  - `removeprunedfunds` now returns RPC_WALLET_ERROR if bitcoind is unable to remove
+  the transaction. Previously returned RPC_INTERNAL_ERROR.
+  - `removeprunedfunds` now returns RPC_INVALID_PARAMETER if the transaction does not
+  exist in the wallet. Previously returned RPC_INTERNAL_ERROR.
+  - `fundrawtransaction` now returns RPC_INVALID_ADDRESS_OR_KEY if an invalid change
+  address is provided. Previously returned RPC_INVALID_PARAMETER.
+  - `fundrawtransaction` now returns RPC_WALLET_ERROR if bitcoind is unable to create
+  the transaction. The error message provides further details. Previously returned
+  RPC_INTERNAL_ERROR.
+  - `bumpfee` now returns RPC_INVALID_PARAMETER if the provided transaction has
+  descendants in the wallet. Previously returned RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_INVALID_PARAMETER if the provided transaction has
+  descendants in the mempool. Previously returned RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction has
+  has been mined or conflicts with a mined transaction. Previously returned
+  RPC_INVALID_ADDRESS_OR_KEY.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction is not
+  BIP 125 replaceable. Previously returned RPC_INVALID_ADDRESS_OR_KEY.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction has already
+  been bumped by a different transaction. Previously returned RPC_INVALID_REQUEST.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction contains
+  inputs which don't belong to this wallet. Previously returned RPC_INVALID_ADDRESS_OR_KEY.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction has multiple change
+  outputs. Previously returned RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the provided transaction has no change
+  output. Previously returned RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the fee is too high. Previously returned
+  RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the fee is too low. Previously returned
+  RPC_MISC_ERROR.
+  - `bumpfee` now returns RPC_WALLET_ERROR if the change output is too small to bump the
+  fee. Previously returned RPC_MISC_ERROR.
+
 Credits
 =======