Use AnyRefMap in MutableSymbolMap

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/Symbols.scala

@@ -637,68 +637,38 @@ object Symbols {
   @sharable var stubs: List[Symbol] = Nil // diagnostic only
 
   /* Mutable map from symbols any T */
-  class MutableSymbolMap[T](private[Symbols] val value: java.util.IdentityHashMap[Symbol, T]) extends AnyVal {
+  class MutableSymbolMap[T](private[Symbols] val value: mutable.AnyRefMap[Symbol, T]) extends AnyVal {
 
-    def apply(sym: Symbol): T = value.get(sym)
+    def apply(sym: Symbol): T = value(sym)
 
-    def get(sym: Symbol): Option[T] = Option(value.get(sym))
+    def get(sym: Symbol): Option[T] = value.get(sym)
 
-    def getOrElse[U >: T](sym: Symbol, default: => U): U = {
-      val v = value.get(sym)
-      if (v != null) v else default
-    }
+    def getOrElse[U >: T](sym: Symbol, default: => U): U = value.getOrElse(sym, default)
 
-    def getOrElseUpdate(sym: Symbol, op: => T): T = {
-      val v = value.get(sym)
-      if (v != null) v
-      else {
-        val v = op
-        assert(v != null)
-        value.put(sym, v)
-        v
-      }
-    }
+    def getOrElseUpdate(sym: Symbol, op: => T): T = value.getOrElseUpdate(sym, op)
 
-    def update(sym: Symbol, x: T): Unit = {
-      assert(x != null)
-      value.put(sym, x)
-    }
-    def put(sym: Symbol, x: T): T = {
-      assert(x != null)
-      value.put(sym, x)
-    }
+    def update(sym: Symbol, x: T): Unit = value.update(sym, x)
 
     def -=(sym: Symbol): Unit = value.remove(sym)
-    def remove(sym: Symbol): Option[T] = Option(value.remove(sym))
+    def remove(sym: Symbol): Option[T] = value.remove(sym)
 
-    def contains(sym: Symbol): Boolean = value.containsKey(sym)
+    def contains(sym: Symbol): Boolean = value.contains(sym)
 
     def isEmpty: Boolean = value.isEmpty
 
     def clear(): Unit = value.clear()
 
-    def filter(p: ((Symbol, T)) => Boolean): Map[Symbol, T] = {
-      import scala.collection.JavaConversions._
-      value.toMap.filter(p)
-    }
+    def filter(p: ((Symbol, T)) => Boolean): Map[Symbol, T] = value.iterator.filter(p).toMap
 
-    def iterator: Iterator[(Symbol, T)] = {
-      import scala.collection.JavaConversions._
-      value.iterator
-    }
+    def iterator: Iterator[(Symbol, T)] = value.iterator
 
-    def keysIterator: Iterator[Symbol] = {
-      import scala.collection.JavaConversions._
-      value.keySet().iterator
-    }
+    def keysIterator: Iterator[Symbol] = value.keysIterator
+
+    def toMap: Map[Symbol, T] = value.toMap
 
-    def toMap: Map[Symbol, T] = {
-      import scala.collection.JavaConversions._
-      value.toMap
-    }
   }
 
   @inline def newMutableSymbolMap[T]: MutableSymbolMap[T] =
-    new MutableSymbolMap(new java.util.IdentityHashMap[Symbol, T]())
+    new MutableSymbolMap(new mutable.AnyRefMap[Symbol, T]())
 
 }