1 files changed, 26 insertions, 1 deletions
diff --git a/Firestore/core/src/firebase/firestore/immutable/sorted_map.h b/Firestore/core/src/firebase/firestore/immutable/sorted_map.h
index 24eb5bf..6f4d91b 100644
--- a/Firestore/core/src/firebase/firestore/immutable/sorted_map.h
+++ b/Firestore/core/src/firebase/firestore/immutable/sorted_map.h
@@ -196,7 +196,12 @@ class SortedMap : public impl::SortedMapBase {
       case Tag::Array:
         return SortedMap{array_.erase(key)};
       case Tag::Tree:
-        return SortedMap{tree_.erase(key)};
+        tree_type result = tree_.erase(key);
+        if (result.empty()) {
+          // Flip back to the array representation for empty arrays.
+          return SortedMap{};
+        }
+        return SortedMap{std::move(result)};
     }
     FIREBASE_UNREACHABLE();
   }
@@ -244,6 +249,26 @@ class SortedMap : public impl::SortedMapBase {
     FIREBASE_UNREACHABLE();
   }
 
+  const_iterator min() const {
+    switch (tag_) {
+      case Tag::Array:
+        return const_iterator(array_.min());
+      case Tag::Tree:
+        return const_iterator{tree_.min()};
+    }
+    FIREBASE_UNREACHABLE();
+  }
+
+  const_iterator max() const {
+    switch (tag_) {
+      case Tag::Array:
+        return const_iterator(array_.max());
+      case Tag::Tree:
+        return const_iterator{tree_.max()};
+    }
+    FIREBASE_UNREACHABLE();
+  }
+
   /**
    * Returns an iterator pointing to the first entry in the map. If there are
    * no entries in the map, begin() == end().