clean the header folder in sandbox (#2716)

* forgot to clean the header folder in sandbox in #2685

chain/src/chain.rs

@@ -852,7 +852,9 @@ impl Chain {
 
 	/// Clean the temporary sandbox folder
 	pub fn clean_txhashset_sandbox(&self) {
-		txhashset::clean_txhashset_folder(&env::temp_dir());
+		let sandbox_dir = env::temp_dir();
+		txhashset::clean_txhashset_folder(&sandbox_dir);
+		txhashset::clean_header_folder(&sandbox_dir);
 	}
 
 	/// Writes a reading view on a txhashset state that's been provided to us.
@@ -879,6 +881,7 @@ impl Chain {
 		// Write txhashset to sandbox (in the os temporary directory)
 		let sandbox_dir = env::temp_dir();
 		txhashset::clean_txhashset_folder(&sandbox_dir);
+		txhashset::clean_header_folder(&sandbox_dir);
 		txhashset::zip_write(sandbox_dir.clone(), txhashset_data.try_clone()?, &header)?;
 
 		let mut txhashset = txhashset::TxHashSet::open(
@@ -949,7 +952,7 @@ impl Chain {
 
 			// Move sandbox to overwrite
 			txhashset.release_backend_files();
-			txhashset::txhashset_replace(sandbox_dir, PathBuf::from(self.db_root.clone()))?;
+			txhashset::txhashset_replace(sandbox_dir.clone(), PathBuf::from(self.db_root.clone()))?;
 
 			// Re-open on db root dir
 			txhashset = txhashset::TxHashSet::open(
@@ -959,6 +962,7 @@ impl Chain {
 			)?;
 
 			self.rebuild_header_mmr(&Tip::from_header(&header), &mut txhashset)?;
+			txhashset::clean_header_folder(&sandbox_dir);
 
 			// Replace the chain txhashset with the newly built one.
 			*txhashset_ref = txhashset;

chain/src/txhashset/txhashset.rs

@@ -1494,6 +1494,16 @@ pub fn clean_txhashset_folder(root_dir: &PathBuf) {
 	}
 }
 
+/// Clean the header folder
+pub fn clean_header_folder(root_dir: &PathBuf) {
+	let header_path = root_dir.clone().join(HEADERHASHSET_SUBDIR);
+	if header_path.exists() {
+		if let Err(e) = fs::remove_dir_all(header_path.clone()) {
+			warn!("clean_header_folder: fail on {:?}. err: {}", header_path, e);
+		}
+	}
+}
+
 fn expected_file(path: &Path) -> bool {
 	use lazy_static::lazy_static;
 	use regex::Regex;