Cancel further enumeration only if callback returns explicit true

Author: Byeol

spec/providers/database.spec.ts

@@ -223,10 +223,10 @@ describe('DeltaSnapshot', () => {
       let count = 0;
       let counter = snap => count++;
 
-      subject.forEach(counter);
+      expect(subject.forEach(counter)).to.equal(false);
       populate(23, null);
 
-      subject.forEach(counter);
+      expect(subject.forEach(counter)).to.equal(false);
       expect(count).to.eq(0);
     });
 
@@ -243,13 +243,21 @@ describe('DeltaSnapshot', () => {
       expect(ret).to.equal(true);
     });
 
-    it('should not cancel further enumeration if callback does not return true', () => {
+    it('should not cancel further enumeration if callback returns a truthy value', () => {
+      populate(null, { a: 'b', c: 'd', e: 'f', g: 'h' });
+      let out = '';
+      const ret = subject.forEach(snap => {
+        out += snap.val();
+        return 1;
+      });
+      expect(out).to.equal('bdfh');
+      expect(ret).to.equal(false);
+    });
+
+    it('should not cancel further enumeration if callback does not return', () => {
       populate(null, { a: 'b', c: 'd', e: 'f', g: 'h' });
       let out = '';
       const ret = subject.forEach(snap => {
-        if (snap.val() === 'a') {
-          return true;
-        }
         out += snap.val();
       });
       expect(out).to.equal('bdfh');

src/providers/database.ts

@@ -209,7 +209,7 @@ export class DeltaSnapshot implements firebase.database.DataSnapshot {
   forEach(action: (a: DeltaSnapshot) => boolean): boolean {
     let val = this.val();
     if (_.isPlainObject(val)) {
-      return _.keys(val).some(key => action(this.child(key)));
+      return _.keys(val).some(key => action(this.child(key)) === true);
     }
     return false;
   }