Merge pull request #1217 from rphmeier/state_at_state_root

Verify the state root exists before creating a State

util/src/journaldb/archivedb.rs

@@ -175,6 +175,8 @@ impl JournalDB for ArchiveDB {
 	fn state(&self, id: &H256) -> Option<Bytes> {
 		self.backing.get_by_prefix(&id.bytes()[0..12]).and_then(|b| Some(b.to_vec()))
 	}
+
+	fn is_pruned(&self) -> bool { false }
 }
 
 #[cfg(test)]

util/src/journaldb/traits.rs

@@ -42,4 +42,7 @@ pub trait JournalDB : HashDB + Send + Sync {
 	fn state(&self, _id: &H256) -> Option<Bytes> {
 		None
 	}
+
+	/// Whether this database is pruned.
+	fn is_pruned(&self) -> bool { true }
 }

util/src/trie/triedb.rs

@@ -59,7 +59,7 @@ impl<'db> TrieDB<'db> {
 	/// Create a new trie with the backing database `db` and `root`
 	/// Panics, if `root` does not exist
 	pub fn new(db: &'db HashDB, root: &'db H256) -> Self {
-		if !db.exists(root) {
+		if !db.contains(root) {
 			flushln!("TrieDB::new({}): Trie root not found!", root);
 			panic!("Trie root not found!");
 		}