From 941f41e62ebcd1e09bc6b364c1fd25c7da107907 Mon Sep 17 00:00:00 2001
From: Yuya Nishihara <yuya@tcha.org>
Date: Thu, 1 Jun 2023 10:39:56 +0900
Subject: [PATCH] tree_builder: initialize base trees with the root entry

This helps to rewrite populate_trees() as recursive function call.
---
 lib/src/tree_builder.rs | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/lib/src/tree_builder.rs b/lib/src/tree_builder.rs
index 1ced009cb..3e51d9ec3 100644
--- a/lib/src/tree_builder.rs
+++ b/lib/src/tree_builder.rs
@@ -115,17 +115,15 @@ impl TreeBuilder {
     }
 
     fn get_base_trees(&self) -> BTreeMap<RepoPath, backend::Tree> {
-        let mut tree_cache = BTreeMap::new();
         let store = self.store.clone();
+        let mut tree_cache = {
+            let dir = RepoPath::root();
+            let tree = store.get_tree(&dir, &self.base_tree_id).unwrap();
+            BTreeMap::from([(dir, tree)])
+        };
 
         let mut populate_trees = |dir: &RepoPath| {
             let mut current_dir = RepoPath::root();
-
-            if !tree_cache.contains_key(&current_dir) {
-                let tree = store.get_tree(&current_dir, &self.base_tree_id).unwrap();
-                tree_cache.insert(current_dir.clone(), tree);
-            }
-
             for component in dir.components() {
                 let next_dir = current_dir.join(component);
                 let current_tree = tree_cache.get(&current_dir).unwrap();