Merge pull request #459 from streamich/delete-lifecycle

Propagate `delete` event

Author: streamich

src/json-crdt/model/Model.ts

@@ -21,6 +21,7 @@ import {AvlMap} from '../../util/trees/avl/AvlMap';
 import type {JsonNode, JsonNodeView} from '../nodes/types';
 import type {Printable} from '../../util/print/types';
 import type {NodeBuilder} from '../../json-crdt-patch';
+import type {NodeApi} from './api/nodes';
 
 export const UNDEFINED = new ConNode(ORIGIN, undefined);
 
@@ -291,6 +292,8 @@ export class Model<N extends JsonNode = JsonNode> implements Printable {
     if (isSystemNode) return;
     const node = this.index.get(value);
     if (!node) return;
+    const api = node.api;
+    if (api) (api as NodeApi).events.onDelete();
     node.children((child) => this.deleteNodeTree(child.id));
     this.index.del(value);
   }

src/json-crdt/model/api/__tests__/NodeEvents.spec.ts

@@ -0,0 +1,25 @@
+import {Model} from '../..';
+
+test('does not fire events after node is deleted', () => {
+  const model = Model.withLogicalClock();
+  model.api.root({
+    foo: {
+      bar: {
+        baz: 'asdf',
+      },
+    },
+  });
+  const bar = model.api.obj(['foo', 'bar']);
+  let cnt = 0;
+  bar.events.changes.listen(() => {
+    cnt++;
+  });
+  expect(cnt).toBe(0);
+  bar.set({
+    gg: 'wp',
+  });
+  expect(cnt).toBe(1);
+  model.api.obj(['foo']).del(['bar']);
+  model.api.obj(['foo']).set({gl: 'hf'});
+  expect(cnt).toBe(1);
+});

src/json-crdt/model/api/events/NodeEvents.ts

@@ -21,9 +21,12 @@ export interface NodeEventMap {
 }
 
 class ChangesFanOut<N extends JsonNode = JsonNode> extends FanOut<JsonNodeView<N>> {
+  /** @ignore */
   private _v: JsonNodeView<N> | undefined = undefined;
+  /** @ignore */
   private _u: FanOutUnsubscribe | undefined = undefined;
 
+  /** @ignore */
   constructor(private readonly api: NodeApi<N>) {
     super();
   }
@@ -45,10 +48,20 @@ class ChangesFanOut<N extends JsonNode = JsonNode> extends FanOut<JsonNodeView<N
       unsubscribe();
       if (!this.listeners.size) {
         this._u?.();
-        // this._unsub = this._view = undefined;
+        this._u = this._v = undefined;
       }
     };
   }
+
+  /**
+   * @internal
+   * @ignore
+   */
+  public dispose() {
+    this.listeners.clear();
+    this._u?.();
+    this._u = this._v = undefined;
+  }
 }
 
 export class NodeEvents<N extends JsonNode = JsonNode>
@@ -101,6 +114,16 @@ export class NodeEvents<N extends JsonNode = JsonNode>
     super.off(type, listener, options);
   }
 
+  /**
+   * Called when this node is deleted.
+   *
+   * @internal
+   * @ignore
+   */
+  public onDelete() {
+    this.changes.dispose();
+  }
+
   // ---------------------------------------------------------------- SyncStore
 
   public readonly subscribe = (callback: () => void): SyncStoreUnsubscribe => {