Correct the argument types of the forEach function

spec/providers/database.spec.ts

@@ -208,7 +208,7 @@ describe('DeltaSnapshot', () => {
  });
  });
 
- describe('#forEach(childAction: Function)', () => {
+ describe('#forEach(action: (a: DeltaSnapshot) => boolean): boolean', () => {
  it('should iterate through child snapshots', () => {
  populate({ a: 'b' }, { c: 'd' });
  let out = '';
@@ -223,12 +223,46 @@ 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);
  });
+
+ it('should cancel further enumeration if callback returns true', () => {
+ populate(null, { a: 'b', c: 'd', e: 'f', g: 'h' });
+ let out = '';
+ const ret = subject.forEach(snap => {
+ if (snap.val() === 'f') {
+ return true;
+ }
+ out += snap.val();
+ });
+ expect(out).to.equal('bd');
+ expect(ret).to.equal(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 => {
+ out += snap.val();
+ });
+ expect(out).to.equal('bdfh');
+ expect(ret).to.equal(false);
+ });
  });
 
  describe('#numChildren()', () => {

src/providers/database.ts

@@ -206,11 +206,10 @@ export class DeltaSnapshot implements firebase.database.DataSnapshot {
  return valAt(this._delta, this._childPath) !== undefined;
  }
 
- // TODO(inlined) what is this boolean for?
  forEach(action: (a: DeltaSnapshot) => boolean): boolean {
  let val = this.val();
  if (_.isPlainObject(val)) {
- _.keys(val).forEach(key => action(this.child(key)));
+ return _.some(val, (value, key: string) => action(this.child(key)) === true);
  }
  return false;
  }