fix: use a Map as the domStylesCache

atom-minimap · Jan 1, 2021 · 108918a · 108918a
1 parent 89f61c2
commit 108918a
Showing 1 changed file with 11 additions and 7 deletions.
diff --git a/lib/dom-styles-reader.js b/lib/dom-styles-reader.js
@@ -11,7 +11,7 @@ export default class DOMStylesReader {
      * The cache object
      * @access private
      */
-    this.domStylesCache = {}
+    this.domStylesCache = new Map()
 
     /**
      * Set to true once tokenized
@@ -38,16 +38,17 @@ export default class DOMStylesReader {
    */
   retrieveStyleFromDom (scopes, property, targetNode, cache = true) {
     const key = scopes.join(' ')
-    let cachedData = this.domStylesCache[key]
+    let cachedData = this.domStylesCache.get(key)
 
-    if (cache && (cachedData ? cachedData[property] : undefined) != null) {
+    if (cache && (cachedData !== undefined ? cachedData[property] : undefined) != null) {
       return cachedData[property]
     }
 
     this.ensureDummyNodeExistence(targetNode)
 
-    if (!cachedData) {
-      this.domStylesCache[key] = cachedData = {}
+    if (cachedData === undefined) {
+      cachedData = {}
+      this.domStylesCache.set(key, cachedData)
     }
 
     let parent = this.dummyNode
@@ -69,7 +70,10 @@ export default class DOMStylesReader {
       value = rotateHue(value, filter)
     }
 
-    if (value !== '') { cachedData[property] = value }
+    if (value !== '') {
+      cachedData[property] = value
+      this.domStylesCache.set(key, cachedData)
+    }
 
     this.dummyNode.innerHTML = ''
     return value
@@ -99,7 +103,7 @@ export default class DOMStylesReader {
    * used in MinimapElement
    */
   invalidateDOMStylesCache () {
-    this.domStylesCache = {}
+    this.domStylesCache.clear()
   }
 
   /**