From 235babfd7f5d57f09201aaf157c84df61e948577 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Ziela=C5=84ski?= <michalzielanski@gmail.com>
Date: Wed, 24 Jun 2020 09:54:56 +0200
Subject: [PATCH] Adaptation of previous changes to the change from 61241e7
 (`null` instead of` undefined` as the initial value)

---
 src/ol/Feature.js                       | 2 +-
 src/ol/Object.js                        | 4 ++--
 src/ol/events/Target.js                 | 8 ++++----
 test/spec/ol/events/eventtarget.test.js | 5 +++++
 4 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/ol/Feature.js b/src/ol/Feature.js
index 3056896278..9ae3b94303 100644
--- a/src/ol/Feature.js
+++ b/src/ol/Feature.js
@@ -129,7 +129,7 @@ class Feature extends BaseObject {
    */
   clone() {
     const clone = new Feature(
-      this.hasProperties() ? this.getProperties() : undefined
+      this.hasProperties() ? this.getProperties() : null
     );
     clone.setGeometryName(this.getGeometryName());
     const geometry = this.getGeometry();
diff --git a/src/ol/Object.js b/src/ol/Object.js
index 90863c8863..c1b62a1c2b 100644
--- a/src/ol/Object.js
+++ b/src/ol/Object.js
@@ -95,7 +95,7 @@ class BaseObject extends Observable {
 
     /**
      * @private
-     * @type {!Object<string, *>}
+     * @type {?Object<string, *>}
      */
     this.values_ = null;
 
@@ -199,7 +199,7 @@ class BaseObject extends Observable {
       const oldValue = this.values_[key];
       delete this.values_[key];
       if (isEmpty(this.values_)) {
-        delete this.values_;
+        this.values_ = null;
       }
       if (!opt_silent) {
         this.notify(key, oldValue);
diff --git a/src/ol/events/Target.js b/src/ol/events/Target.js
index efd9737725..eea7c1624a 100644
--- a/src/ol/events/Target.js
+++ b/src/ol/events/Target.js
@@ -40,19 +40,19 @@ class Target extends Disposable {
 
     /**
      * @private
-     * @type {Object<string, number>}
+     * @type {?Object<string, number>}
      */
     this.pendingRemovals_ = null;
 
     /**
      * @private
-     * @type {Object<string, number>}
+     * @type {?Object<string, number>}
      */
     this.dispatching_ = null;
 
     /**
      * @private
-     * @type {Object<string, Array<import("../events.js").Listener>>}
+     * @type {?Object<string, Array<import("../events.js").Listener>>}
      */
     this.listeners_ = null;
   }
@@ -143,7 +143,7 @@ class Target extends Disposable {
    * @return {Array<import("../events.js").Listener>|undefined} Listeners.
    */
   getListeners(type) {
-    return this.listeners_ && this.listeners_[type];
+    return (this.listeners_ && this.listeners_[type]) || undefined;
   }
 
   /**
diff --git a/test/spec/ol/events/eventtarget.test.js b/test/spec/ol/events/eventtarget.test.js
index 48ef6c9b3a..90bf63ce59 100644
--- a/test/spec/ol/events/eventtarget.test.js
+++ b/test/spec/ol/events/eventtarget.test.js
@@ -33,6 +33,11 @@ describe('ol.events.EventTarget', function () {
       });
       target.dispatchEvent('my-event');
     });
+    it('does not initialize objects in advance', function () {
+      expect(eventTarget.pendingRemovals_).to.be(null);
+      expect(eventTarget.dispatching_).to.be(null);
+      expect(eventTarget.listeners_).to.be(null);
+    });
   });
 
   describe('#hasListener', function () {