Trie simplification. (#2815)

* switch to simple codec, trie broken for now

* Actualy use trie_root_noext

* align some hash, failing test on EMCH comment

* Fix trie code over layout instead of hash, revert legacy code for legacy
mainnet ??

* stub behind LayOut

* fix no_std

* temp solution for legacy trie behind feature legacy-key in various crate

* use remote project

* rc client db need prefix

* update trie deps

* bum spec runtime version

* Removing legacy as default.

* Switch mode to non legacy.

* bump runtime version

* Remove legacy trie compatibility features.

* fix warning

* bump version

* change hash on new test.

* Move dependency (#11 trie PR) patched to a parity repo.
Bench reverted to correct hasher.
Some renaming and doc improvments.

* ChildBitmap renaming to BitMap.

* Renaming of LayOut to Layout.

* formatting.

* Removing abreviation such as _ix nb_ or bm.

* Update deps and apply renaming 'Buff' -> 'Buffer'.

* Align to latest trie crates naming changes.

* Update trie dependency.

* Update trie dependency.

* change block_import test hash

* update trie deps (trie use new scale codec but it does not seems to be
an issue).

* update to use latest trie version (no mgmt of multiple radix).

* tabify

* Restoring test to 10 000.

* Use published crate, trie bench is currently down until publishing
(require another pr to update version).

* Update trie-bench.

substrate/core/state-machine/src/changes_trie/changes_iterator.rs

@@ -20,7 +20,7 @@
 use std::cell::RefCell;
 use std::collections::VecDeque;
 use parity_codec::{Decode, Encode};
-use hash_db::{HashDB, Hasher};
+use hash_db::{HashDB, Hasher, EMPTY_PREFIX};
 use num_traits::One;
 use trie::{Recorder, MemoryDB};
 use crate::changes_trie::{AnchorBlockId, Configuration, RootsStorage, Storage, BlockNumber};
@@ -115,7 +115,7 @@ pub fn key_changes_proof_check<S: RootsStorage<H, Number>, H: Hasher, Number: Bl
 
 	let mut proof_db = MemoryDB::<H>::default();
 	for item in proof {
-		proof_db.insert(&[], &item);
+		proof_db.insert(EMPTY_PREFIX, &item);
 	}
 
 	let proof_db = InMemoryStorage::with_db(proof_db);

substrate/core/state-machine/src/changes_trie/mod.rs

@@ -46,14 +46,15 @@ pub use self::storage::InMemoryStorage;
 pub use self::changes_iterator::{key_changes, key_changes_proof, key_changes_proof_check};
 pub use self::prune::{prune, oldest_non_pruned_trie};
 
-use hash_db::Hasher;
+use hash_db::{Hasher, Prefix};
 use crate::backend::Backend;
 use num_traits::{One, Zero};
 use parity_codec::{Decode, Encode};
 use primitives;
 use crate::changes_trie::build::prepare_input;
 use crate::overlayed_changes::OverlayedChanges;
-use trie::{MemoryDB, TrieDBMut, TrieMut, DBValue};
+use trie::{MemoryDB, DBValue, TrieMut};
+use trie::trie_types::TrieDBMut;
 
 /// Changes that are made outside of extrinsics are marked with this index;
 pub const NO_EXTRINSIC_INDEX: u32 = 0xffffffff;
@@ -108,7 +109,7 @@ pub trait RootsStorage<H: Hasher, Number: BlockNumber>: Send + Sync {
 /// Changes trie storage. Provides access to trie roots and trie nodes.
 pub trait Storage<H: Hasher, Number: BlockNumber>: RootsStorage<H, Number> {
 	/// Get a trie node.
-	fn get(&self, key: &H::Out, prefix: &[u8]) -> Result<Option<DBValue>, String>;
+	fn get(&self, key: &H::Out, prefix: Prefix) -> Result<Option<DBValue>, String>;
 }
 
 /// Changes trie storage -> trie backend essence adapter.
@@ -117,7 +118,7 @@ pub struct TrieBackendStorageAdapter<'a, H: Hasher, Number: BlockNumber>(pub &'a
 impl<'a, H: Hasher, N: BlockNumber> crate::TrieBackendStorage<H> for TrieBackendStorageAdapter<'a, H, N> {
 	type Overlay = trie::MemoryDB<H>;
 
-	fn get(&self, key: &H::Out, prefix: &[u8]) -> Result<Option<DBValue>, String> {
+	fn get(&self, key: &H::Out, prefix: Prefix) -> Result<Option<DBValue>, String> {
 		self.0.get(key, prefix)
 	}
 }

substrate/core/state-machine/src/changes_trie/storage.rs

@@ -17,7 +17,7 @@
 //! Changes trie storage utilities.
 
 use std::collections::BTreeMap;
-use hash_db::Hasher;
+use hash_db::{Hasher, Prefix};
 use trie::DBValue;
 use trie::MemoryDB;
 use parking_lot::RwLock;
@@ -101,7 +101,7 @@ impl<H: Hasher, Number: BlockNumber> InMemoryStorage<H, Number> {
 	pub fn remove_from_storage(&self, keys: &HashSet<H::Out>) {
 		let mut data = self.data.write();
 		for key in keys {
-			data.mdb.remove_and_purge(key, &[]);
+			data.mdb.remove_and_purge(key, hash_db::EMPTY_PREFIX);
 		}
 	}
 
@@ -132,7 +132,7 @@ impl<H: Hasher, Number: BlockNumber> RootsStorage<H, Number> for InMemoryStorage
 }
 
 impl<H: Hasher, Number: BlockNumber> Storage<H, Number> for InMemoryStorage<H, Number> {
-	fn get(&self, key: &H::Out, prefix: &[u8]) -> Result<Option<DBValue>, String> {
+	fn get(&self, key: &H::Out, prefix: Prefix) -> Result<Option<DBValue>, String> {
 		MemoryDB::<H>::get(&self.data.read().mdb, key, prefix)
 	}
 }
@@ -151,7 +151,7 @@ impl<'a, H, Number, S> TrieBackendStorage<H> for TrieBackendAdapter<'a, H, Numbe
 {
 	type Overlay = MemoryDB<H>;
 
-	fn get(&self, key: &H::Out, prefix: &[u8]) -> Result<Option<DBValue>, String> {
+	fn get(&self, key: &H::Out, prefix: Prefix) -> Result<Option<DBValue>, String> {
 		self.storage.get(key, prefix)
 	}
 }