FIX #791 auto-bind methods of RxDocument to the instance

CHANGELOG.md

@@ -20,6 +20,7 @@ Features:
   - Added `RxReplicationState.denied$` [#763](https://github.com/pubkey/rxdb/issues/763)
   - Added option for CORS to server-plugin
   - `this`-scope of collection-hooks are bound to the collection itself [#788](https://github.com/pubkey/rxdb/issues/788)
+  - All methods of `RxDocument` are bound to the instance [#791](https://github.com/pubkey/rxdb/issues/791)
 
 Bugfixes:
   - checkAdapter doesn't cleanup test databases [#714](https://github.com/pubkey/rxdb/issues/714)

docs-src/rx-document.md

@@ -169,6 +169,10 @@ myDocument.name = 'foobar';
 await myDocument.save(); // submit the changes to the storage
 ```
 
+## NOTICE: All methods of RxDocument are bound to the instance
+
+When you get a method from a `RxDocument`, the method is automatically bound to the documents instance. This means you do not have to use things like `myMethod.bind(myDocument)` like you would do in jsx.
+
 
 ### isRxDocument
 Returns true if the given object is an instance of RxDocument. Returns false if not.

src/rx-collection.js

@@ -123,11 +123,23 @@ export class RxCollection {
                 const props = Object.getOwnPropertyNames(obj);
                 props.forEach(key => {
                     const desc = Object.getOwnPropertyDescriptor(obj, key);
-                    desc.enumerable = false;
-                    desc.configurable = false;
-                    if (desc.writable)
-                        desc.writable = false;
-                    Object.defineProperty(proto, key, desc);
+                    if (typeof desc.value === 'function') {
+                        // when getting a function, we automatically do a .bind(this)
+                        Object.defineProperty(proto, key, {
+                            get() {
+                                return desc.value.bind(this);
+                            },
+                            enumerable: false,
+                            configurable: false
+                        });
+
+                    } else {
+                        desc.enumerable = false;
+                        desc.configurable = false;
+                        if (desc.writable)
+                            desc.writable = false;
+                        Object.defineProperty(proto, key, desc);
+                    }
                 });
             });
 

test/unit/orm.test.js

@@ -340,4 +340,71 @@ config.parallel('orm.test.js', () => {
             });
         });
     });
+    describe('ISSUES', () => {
+        it('#791 Document methods are not bind() to the document', async () => {
+            const db = await RxDB.create({
+                name: util.randomCouchString(),
+                adapter: 'memory',
+                multiInstance: false
+            });
+
+            const schema = {
+                version: 0,
+                type: 'object',
+                primaryPath: '_id',
+                properties: {
+                    name: {
+                        type: 'string'
+                    },
+                    nested: {
+                        type: 'object',
+                        properties: {
+                            foo: {
+                                type: 'string'
+                            }
+                        }
+                    }
+                }
+            };
+
+            const collection = await db.collection({
+                name: 'person',
+                schema: schema,
+                methods: {
+                    hello: function() {
+                        return this.name;
+                    }
+                }
+            });
+
+            const doc = await collection.insert({
+                name: 'hi',
+                nested: {
+                    foo: 'bar'
+                }
+            });
+
+            // orm-method
+            const hello = doc.hello;
+            assert.equal(hello(), 'hi');
+
+            // prototype-method
+            const get = doc.get;
+            assert.equal(get('name'), 'hi');
+
+            // nested
+            const nestedObj = doc.nested;
+            assert.equal(nestedObj.foo, 'bar');
+
+            // nested getter-method
+            const obs = nestedObj.foo$;
+            const emitted = [];
+            const sub = obs.subscribe(v => emitted.push(v));
+            await AsyncTestUtil.waitUntil(() => emitted.length === 1);
+            assert.equal(emitted[0], 'bar');
+            sub.unsubscribe();
+
+            db.destroy();
+        });
+    });
 });