Merge pull request #912 from somombo/@somombo/add-list-set

feat(FirebaseListObservable): add `set` method for destructive updates

Author: jamesdaniels

docs/3-retrieving-data-as-lists.md

@@ -120,7 +120,19 @@ const items = db.list('/items');
 items.push({ name: newName });
 ```
 
-### Updating items in the list
+### Replacing items in the list using `set`
+
+Use the `set()` method to update existing items.
+
+```ts
+const items = af.database.list('/items');
+// to get a key, check the Example app below
+items.set('key-of-some-data', { size: newSize });
+```
+
+Replaces the current value in the database with the new value specified as the parameter. This is called a destructive update, because it deletes everything currently in place and saves the new value.
+
+### Updating items in the list using `update`
 
 Use the `update()` method to update existing items.
 
@@ -130,6 +142,8 @@ const items = db.list('/items');
 items.update('key-of-some-data', { size: newSize });
 ```
 
+Note that this updates the current value with in the database with the new value specified as the parameter. This is called a non-destructive update, because it only updates the values specified.
+
 ### Removing items from the list
 Use the `remove()` method to remove data at the list item's location.
 

src/database/firebase_list_observable.spec.ts

@@ -145,6 +145,99 @@ describe('FirebaseListObservable', () => {
     })
   });
 
+
+  describe('set', () => {
+    let orphan = { orphan: true };
+    let child:firebase.database.Reference;
+
+    beforeEach(() => {
+      child = ref.push(orphan);
+    });
+
+    it('should set(replace) the item from the Firebase db when given the key', (done:any) => {
+      let childChangedSpy = jasmine.createSpy('childChanged');
+      const orphanChange = { changed: true }
+      ref.on('child_changed', childChangedSpy);
+      O.set(child.key, orphanChange)
+        .then(() => (<any>ref).once('value'))
+        .then((data:firebase.database.DataSnapshot) => {
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).not.toEqual({
+            orphan: true,
+            changed: true
+          });
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).toEqual({
+            changed: true
+          });
+
+          ref.off();
+        })
+        .then(done, done.fail);
+    });
+
+    it('should set(replace) the item from the Firebase db when given the reference', (done:any) => {
+      let childChangedSpy = jasmine.createSpy('childChanged');
+      const orphanChange = { changed: true }
+      ref.on('child_changed', childChangedSpy);
+      O.set(child.ref, orphanChange)
+        .then(() => (<any>ref).once('value'))
+        .then((data:firebase.database.DataSnapshot) => {
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).not.toEqual({
+            orphan: true,
+            changed: true
+          });
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).toEqual({
+            changed: true
+          });
+
+          ref.off();
+        })
+        .then(done, done.fail);
+    });
+
+    it('should set(replace) the item from the Firebase db when given the snapshot', (done:any) => {
+      let childChangedSpy = jasmine.createSpy('childChanged');
+      const orphanChange = { changed: true }
+      ref.on('child_changed', childChangedSpy);
+      O.set(child, orphanChange)
+        .then(() => (<any>ref).once('value'))
+        .then((data:firebase.database.DataSnapshot) => {
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).not.toEqual({
+            orphan: true,
+            changed: true
+          });
+          expect(childChangedSpy.calls.argsFor(0)[0].val()).toEqual({
+            changed: true
+          });
+
+          ref.off();
+        })
+        .then(done, done.fail);
+    });
+
+    it('should set(replace) the item from the Firebase db when given the unwrapped snapshot', (done:any) => {
+      const orphanChange = { changed: true }
+      ref.on('child_added', (data:firebase.database.DataSnapshot) => {
+        expect(data.val()).toEqual(orphan);
+        O.set(unwrapMapFn(data), orphanChange)
+          .then(() => (<any>child).once('value'))
+          .then((data:firebase.database.DataSnapshot) => {
+            expect(data.val()).not.toEqual({
+              orphan: true,
+              changed: true
+            });
+            expect(data.val()).toEqual({
+              changed: true
+            });
+            ref.off();
+          })
+          .then(done, done.fail);
+      });
+    });
+
+  });
+
+
+
   describe('update', () => {
     let orphan = { orphan: true };
     let child:firebase.database.Reference;

src/database/firebase_list_observable.ts

@@ -28,6 +28,15 @@ export class FirebaseListObservable<T> extends Observable<T> {
     return this.$ref.ref.push(val);
   }
 
+  set(item: FirebaseOperation, value: Object): firebase.Promise<void> {
+    return this._checkOperationCases(item, {
+      stringCase: () => this.$ref.ref.child(<string>item).set(value),
+      firebaseCase: () => (<firebase.database.Reference>item).set(value),
+      snapshotCase: () => (<firebase.database.DataSnapshot>item).ref.set(value),
+      unwrappedSnapshotCase: () => this.$ref.ref.child((<AFUnwrappedDataSnapshot>item).$key).set(value)
+    });
+  }
+
   update(item: FirebaseOperation, value: Object): firebase.Promise<void> {
     return this._checkOperationCases(item, {
       stringCase: () => this.$ref.ref.child(<string>item).update(value),
@@ -50,7 +59,7 @@ export class FirebaseListObservable<T> extends Observable<T> {
     });
   }
 
-  _checkOperationCases(item: FirebaseOperation, cases: FirebaseOperationCases) : firebase.Promise<void> {
+  protected _checkOperationCases(item: FirebaseOperation, cases: FirebaseOperationCases) : firebase.Promise<void> {
     if (utils.isString(item)) {
       return cases.stringCase();
     } else if (utils.isFirebaseRef(item)) {