fix: use Map for decorationsById

Author: aminya

lib/mixins/decoration-management.js

@@ -31,7 +31,7 @@ export default class DecorationManagement {
      * @type {Object}
      * @access private
      */
-    this.decorationsById = {}
+    this.decorationsById = new Map()
     /**
      * The decorations stored in an array indexed with their marker id.
      * @type {Object}
@@ -74,12 +74,7 @@ export default class DecorationManagement {
    * @return {Array<Decoration>} all the decorations in this `Minimap`
    */
   getDecorations () {
-    const decorations = this.decorationsById
-    const results = []
-
-    for (const id in decorations) { results.push(decorations[id]) }
-
-    return results
+    return this.decorationsById.values()
   }
 
   /**
@@ -173,7 +168,7 @@ export default class DecorationManagement {
    * @return {Decoration} the decoration with the given id
    */
   decorationForId (id) {
-    return this.decorationsById[id]
+    return this.decorationsById.get(id)
   }
 
   /**
@@ -235,8 +230,10 @@ export default class DecorationManagement {
     }
 
     const cache = {}
-    for (const id in this.decorationsById) {
-      const decoration = this.decorationsById[id]
+
+    const decorations = this.decorationsById.values()
+    for (const decoration of decorations) {
+
       const range = decoration.marker.getScreenRange()
       const type = decoration.getProperties().type
 
@@ -403,7 +400,7 @@ export default class DecorationManagement {
     }
 
     this.decorationsByMarkerId[id].push(decoration)
-    this.decorationsById[decoration.id] = decoration
+    this.decorationsById.set(decoration.id, decoration)
 
     if (this.decorationUpdatedSubscriptions[decoration.id] == null) {
       this.decorationUpdatedSubscriptions[decoration.id] =
@@ -527,7 +524,7 @@ export default class DecorationManagement {
     const marker = decoration.marker
     let subscription
 
-    delete this.decorationsById[decoration.id]
+    this.decorationsById.delete(decoration.id)
 
     subscription = this.decorationUpdatedSubscriptions[decoration.id]
     if (subscription != null) { subscription.dispose() }
@@ -623,11 +620,12 @@ export default class DecorationManagement {
       this.decorationDestroyedSubscriptions[id].dispose()
     }
 
-    for (const id in this.decorationsById) {
-      this.decorationsById[id].destroy()
+    const decorationsByIdValues = this.decorationsById.values()
+    for (const decoration of decorationsByIdValues) {
+      decoration.destroy()
     }
 
-    this.decorationsById = {}
+    this.decorationsById.clear()
     this.decorationsByMarkerId = {}
     this.decorationMarkerChangedSubscriptions = {}
     this.decorationMarkerDestroyedSubscriptions = {}

spec/minimap-spec.js

@@ -412,7 +412,7 @@ describe('Minimap', () => {
       })
 
       it('removes all the previously added decorations', () => {
-        expect(minimap.decorationsById).toEqual({})
+        expect(minimap.decorationsById.size).toEqual(0)
         expect(minimap.decorationsByMarkerId).toEqual({})
       })