--- a/rust/hg-core/src/dirstate/dirstate_map.rs	Wed Sep 30 18:10:53 2020 +0200
+++ b/rust/hg-core/src/dirstate/dirstate_map.rs	Wed Sep 30 18:10:29 2020 +0200
@@ -16,7 +16,6 @@
     CopyMap, DirsMultiset, DirstateEntry, DirstateError, DirstateMapError,
     DirstateParents, DirstateParseError, FastHashMap, StateMap,
 };
-use core::borrow::Borrow;
 use micro_timer::timed;
 use std::collections::HashSet;
 use std::convert::TryInto;
@@ -67,7 +66,7 @@
     }
 
     pub fn clear(&mut self) {
-        self.state_map.clear();
+        self.state_map = StateMap::default();
         self.copy_map.clear();
         self.file_fold_map = None;
         self.non_normal_set = None;
@@ -189,18 +188,15 @@
     ) {
         for filename in filenames {
             let mut changed = false;
-            self.state_map
-                .entry(filename.to_owned())
-                .and_modify(|entry| {
-                    if entry.state == EntryState::Normal && entry.mtime == now
-                    {
-                        changed = true;
-                        *entry = DirstateEntry {
-                            mtime: MTIME_UNSET,
-                            ..*entry
-                        };
-                    }
-                });
+            if let Some(entry) = self.state_map.get_mut(&filename) {
+                if entry.state == EntryState::Normal && entry.mtime == now {
+                    changed = true;
+                    *entry = DirstateEntry {
+                        mtime: MTIME_UNSET,
+                        ..*entry
+                    };
+                }
+            }
             if changed {
                 self.get_non_normal_other_parent_entries()
                     .0
@@ -257,6 +253,7 @@
         )
     }
 
+    #[cfg(not(feature = "dirstate-tree"))]
     pub fn set_non_normal_other_parent_entries(&mut self, force: bool) {
         if !force
             && self.non_normal_set.is_some()
@@ -285,6 +282,34 @@
         self.non_normal_set = Some(non_normal);
         self.other_parent_set = Some(other_parent);
     }
+    #[cfg(feature = "dirstate-tree")]
+    pub fn set_non_normal_other_parent_entries(&mut self, force: bool) {
+        if !force
+            && self.non_normal_set.is_some()
+            && self.other_parent_set.is_some()
+        {
+            return;
+        }
+        let mut non_normal = HashSet::new();
+        let mut other_parent = HashSet::new();
+
+        for (
+            filename,
+            DirstateEntry {
+                state, size, mtime, ..
+            },
+        ) in self.state_map.iter()
+        {
+            if state != EntryState::Normal || mtime == MTIME_UNSET {
+                non_normal.insert(filename.to_owned());
+            }
+            if state == EntryState::Normal && size == SIZE_FROM_OTHER_PARENT {
+                other_parent.insert(filename.to_owned());
+            }
+        }
+        self.non_normal_set = Some(non_normal);
+        self.other_parent_set = Some(other_parent);
+    }
 
     /// Both of these setters and their uses appear to be the simplest way to
     /// emulate a Python lazy property, but it is ugly and unidiomatic.
@@ -398,17 +423,33 @@
         self.set_non_normal_other_parent_entries(true);
         Ok(packed)
     }
-
+    #[cfg(not(feature = "dirstate-tree"))]
     pub fn build_file_fold_map(&mut self) -> &FileFoldMap {
         if let Some(ref file_fold_map) = self.file_fold_map {
             return file_fold_map;
         }
         let mut new_file_fold_map = FileFoldMap::default();
-        for (filename, DirstateEntry { state, .. }) in self.state_map.borrow()
-        {
+
+        for (filename, DirstateEntry { state, .. }) in self.state_map.iter() {
             if *state == EntryState::Removed {
                 new_file_fold_map
-                    .insert(normalize_case(filename), filename.to_owned());
+                    .insert(normalize_case(&filename), filename.to_owned());
+            }
+        }
+        self.file_fold_map = Some(new_file_fold_map);
+        self.file_fold_map.as_ref().unwrap()
+    }
+    #[cfg(feature = "dirstate-tree")]
+    pub fn build_file_fold_map(&mut self) -> &FileFoldMap {
+        if let Some(ref file_fold_map) = self.file_fold_map {
+            return file_fold_map;
+        }
+        let mut new_file_fold_map = FileFoldMap::default();
+
+        for (filename, DirstateEntry { state, .. }) in self.state_map.iter() {
+            if state == EntryState::Removed {
+                new_file_fold_map
+                    .insert(normalize_case(&filename), filename.to_owned());
             }
         }
         self.file_fold_map = Some(new_file_fold_map);