Merge aa9666b into 2f7b744

src/controller/datacontroller.js

@@ -351,7 +351,14 @@ export default class DataController {
 	/**
 	 * Removes all event listeners set by the DataController.
 	 */
-	destroy() {}
+	destroy() {
+		this.stopListening();
+		this.model = null;
+		this.processor = null;
+		this.mapper = null;
+		this.downcastDispatcher = null;
+		this.upcastDispatcher = null;
+	}
 
 	/**
 	 * Checks if all provided root names are existing editor roots.

src/controller/editingcontroller.js

@@ -130,6 +130,10 @@ export default class EditingController {
 	 */
 	destroy() {
 		this.view.destroy();
+		this.view = null;
+		this.model = null;
+		this.mapper = null;
+		this.history = null;
 		this.stopListening();
 	}
 }

src/model/document.js

@@ -230,6 +230,8 @@ export default class Document {
 	destroy() {
 		this.selection.destroy();
 		this.stopListening();
+		this.selection = null;
+		this.model = null;
 	}
 
 	/**

src/model/documentselection.js

@@ -316,6 +316,7 @@ export default class DocumentSelection {
 	 */
 	destroy() {
 		this._selection.destroy();
+		this._selection = null;
 	}
 
 	/**
@@ -666,6 +667,7 @@ class LiveSelection extends Selection {
 		for ( let i = 0; i < this._ranges.length; i++ ) {
 			this._ranges[ i ].detach();
 		}
+		this.markers = null;
 
 		this.stopListening();
 	}

src/model/model.js

@@ -671,7 +671,10 @@ export default class Model {
 	 */
 	destroy() {
 		this.document.destroy();
+		this.document = null;
 		this.stopListening();
+		this.markers = null;
+		this.document = null;
 	}
 
 	/**

src/view/document.js

@@ -121,6 +121,13 @@ export default class Document {
 		this._postFixers.add( postFixer );
 	}
 
+	destroy() {
+		this.roots.map( root => root.destroy() );
+		this.roots.clear();
+		this.roots = null;
+		this.stopListening();
+	}
+
 	/**
 	 * Performs post-fixer loops. Executes post-fixer callbacks as long as none of them has done any changes to the model.
 	 *

src/view/editableelement.js

@@ -77,6 +77,10 @@ export default class EditableElement extends ContainerElement {
 		}
 	}
 
+	destroy() {
+		this.stopListening();
+	}
+
 	/**
 	 * Returns document associated with the editable.
 	 *

src/view/filler.js

@@ -58,6 +58,7 @@ export const BR_FILLER = domDocument => {
  * @function
  */
 export const NBSP_FILLER = domDocument => domDocument.createTextNode( '\u00A0' );
+// TODO: The NBSP_FILLER leaks detachted textNode.
 
 /**
  * Length of the {@link module:engine/view/filler~INLINE_FILLER INLINE_FILLER}.

src/view/observer/fakeselectionobserver.js

@@ -65,6 +65,7 @@ export default class FakeSelectionObserver extends Observer {
 		super.destroy();
 
 		this._fireSelectionChangeDoneDebounced.cancel();
+		this._fireSelectionChangeDoneDebounced = null;
 	}
 
 	/**

src/view/observer/mutationobserver.js

@@ -124,6 +124,11 @@ export default class MutationObserver extends Observer {
 		super.destroy();
 
 		this._mutationObserver.disconnect();
+
+		this.domConverter = null;
+		this.renderer = null;
+		this._domElements = null;
+		this._mutationObserver = null;
 	}
 
 	/**

src/view/observer/observer.js

@@ -80,6 +80,8 @@ export default class Observer {
 	destroy() {
 		this.disable();
 		this.stopListening();
+		this.view = null;
+		this.document = null;
 	}
 
 	/**

src/view/observer/selectionobserver.js

@@ -116,6 +116,14 @@ export default class SelectionObserver extends Observer {
 
 		clearInterval( this._clearInfiniteLoopInterval );
 		this._fireSelectionChangeDoneDebounced.cancel();
+
+		this._fireSelectionChangeDoneDebounced = null;
+		this._clearInfiniteLoopInterval = null;
+
+		this.mutationObserver = null;
+		this.selection = null;
+		this.domConverter = null;
+		this._documents = null;
 	}
 
 	/**

src/view/view.js

@@ -398,7 +398,15 @@ export default class View {
 			observer.destroy();
 		}
 
+		this.document.destroy();
+
 		this.stopListening();
+		this.document = null;
+		this.domConverter = null;
+		this._renderer = null;
+		this._writer = null;
+		this.domRoots.clear();
+		this.domRoots = null;
 	}
 
 	/**