Merge pull request #667 from streamich/string-store

Stor sub-binding functionality

Author: streamich

src/json-crdt/json-patch/JsonPatchStore.ts

@@ -1,6 +1,7 @@
 import {SyncStore} from '../../util/events/sync-store';
 import {JsonNodeApi} from '../model/api/types';
 import {JsonPatch} from './JsonPatch';
+import {toPath} from '../../json-pointer/util';
 import type {Path} from '../../json-pointer/types';
 import type {Model} from '../model';
 import type {Operation} from '../../json-patch';
@@ -28,6 +29,10 @@ export class JsonPatchStore<N extends JsonNode = JsonNode<any>> implements SyncS
     this.patcher.apply(ops);
   };
 
+  public bind(path: string | Path): JsonPatchStore<N> {
+    return new JsonPatchStore(this.model, this.path.concat(toPath(path)));
+  }
+
   // ---------------------------------------------------------------- SyncStore
 
   public readonly subscribe = (callback: () => void) => this.api.events.onChanges.listen(() => callback());

src/json-crdt/json-patch/__tests__/JsonPatchStore.spec.ts

@@ -61,3 +61,45 @@ test('can subscribe and unsubscribe to changes', async () => {
     counter: 123,
   });
 });
+
+test('can bind to a sub-path', async () => {
+  const model = Model.create(
+    s.obj({
+      ui: s.obj({
+        state: s.obj({
+          text: s.str('abc'),
+          counter: s.con(123),
+        }),
+      }),
+    }),
+  );
+  const store = new JsonPatchStore(model, ['ui']);
+  const store2 = store.bind(['state']);
+  expect(store2.getSnapshot()).toEqual({
+    text: 'abc',
+    counter: 123,
+  });
+  store2.update({op: 'str_ins', path: '/text', pos: 3, str: 'x'});
+  expect(store2.getSnapshot()).toEqual({
+    text: 'abcx',
+    counter: 123,
+  });
+});
+
+test('can bind store to a "str" node', async () => {
+  const model = Model.create(
+    s.obj({
+      ui: s.obj({
+        state: s.obj({
+          text: s.str('abc'),
+          counter: s.con(123),
+        }),
+      }),
+    }),
+  );
+  const store = new JsonPatchStore(model, ['ui']);
+  const store2 = store.bind('/state/text');
+  expect(store2.getSnapshot()).toEqual('abc');
+  store2.update({op: 'str_ins', path: '', pos: 3, str: 'x'});
+  expect(store2.getSnapshot()).toEqual('abcx');
+});