refactor(linked_hash_map): prevent rehashing

Author: FlyCloudC

builtin/linked_hash_map.mbt

@@ -68,6 +68,11 @@ pub fn[K, V] Map::new(capacity? : Int = 8) -> Map[K, V] {
 ///|
 /// Create a hash map from array.
 pub fn[K : Hash + Eq, V] Map::from_array(arr : Array[(K, V)]) -> Map[K, V] {
+  let length = arr.length()
+  let mut capacity = length.next_power_of_two()
+  if length >= calc_grow_threshold(capacity) {
+    capacity *= 2
+  }
   let m = Map::new(capacity=arr.length())
   arr.each(e => m.set(e.0, e.1))
   m
@@ -623,6 +628,10 @@ pub impl[K : Hash + Eq, V : Eq] Eq for Map[K, V] with equal(
 ///|
 pub fn[K : Hash + Eq, V] Map::of(arr : FixedArray[(K, V)]) -> Map[K, V] {
   let length = arr.length()
+  let mut capacity = length.next_power_of_two()
+  if length >= calc_grow_threshold(capacity) {
+    capacity *= 2
+  }
   let m = Map::new(capacity=length)
   // arr.iter((e) => { m.set(e.0, e.1) })
   for i in 0..<length {