Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

bindNodeCallback returns incorrect result if undefined success argument in callback #2254

Closed
stusherwin opened this issue Jan 6, 2017 · 2 comments

Comments

@stusherwin
Copy link

stusherwin commented Jan 6, 2017

RxJS version:
5.0.0-beta.6 but bug is present in master as of f8ba77d

Code to reproduce:

let nodeFunction = function(param1: string, param2: string, callback: any) {
  // Bug only manifests when success parameter is implicitly undefined
  callback(null /*error*/); // no success parameter
}

Observable.bindNodeCallback(nodeFunction)('a', 'b')
  .subscribe(succ => console.log(succ));

Expected behavior:
undefined

Actual behavior:
[]

Additional information:
This is a bug IMO because it does not preserve the behaviour of the wrapped method. There are actual libraries in production that have this behaviour, e.g. node-sqlite3 (which is how I found it):

Database#get(sql, [param, ...], [callback])

Runs the SQL query with the specified parameters and calls the callback with the first result row afterwards [...] The signature of the callback is function(err, row) {}. If the result set is empty, the second parameter is undefined, otherwise it is an object containing the values for the first row.

The problem appears to be in this line:
https://github.com/ReactiveX/rxjs/blob/master/src/observable/BoundNodeCallbackObservable.ts#L109

It could be fixed with something like this:

if(!innerArgs.length) {
  subject.next(undefined);
} else {
  subject.next(innerArgs.length === 1 ? innerArgs[0] : innerArgs);
}

But there's probably a more elegant way of doing it!

@trxcllnt
Copy link
Member

trxcllnt commented Jan 8, 2017

@stusherwin you're right, that's the correct fix. Happy to review if you want to submit a PR.

trxcllnt pushed a commit to trxcllnt/rxjs that referenced this issue Feb 15, 2017
…guments

Emit undefined insteady of empty array by resulting Observable,
when callback function is called without success parameters.

Closes ReactiveX#2254
benlesh pushed a commit that referenced this issue Mar 27, 2017
* fix(timeout): Cancels scheduled timeout, if no longer needed

fixes #2134

* fix(timeoutWith): Cancels scheduled timeout, if no longer needed

* build(npm-scripts): update debug_mocha npm script for node 6

* fix(VirtualAction): Block rescheduled VirtualActions from executing their scheduled work.

VirtualActions are immutable so they can be inspected by the TestScheduler. In order to mirror

rescheduled stateful Actions, rescheduled VirtualActions shouldn't execute if they've been

rescheduled before execution.

* fix(timeout): Update timeout and timeoutWith to recycle their scheduled timeout actions.

The timeout and timeoutWith operators should dispose their scheduled timeout actions on

unsubscription. Also, given the new scheduling architecture, they can recycle their scheduled

actions so just one action is allocated per subscription.

* test(timeout): Add types to timeout and timeoutWith specs

* Fix merge conflicts

* Fix timeoutWith to work with new Subscriber leak fix.

* fix(timeout-spec): fix merge conflicts

* fix(Subscription): fold ChildSubscription logic into Subscriber to prevent operators from leaking ChildSubscriptions. (#2360)

The addition of ChildSubscription to fix #2244 accidentally introduced a different memory leak. Most operators that add and remove inner Subscriptions store the inner Subscriber instance, not the value returned by Subscription#add. When they try to remove the inner Subscription manually, nothing is removed, because the ChildSubscription wrapper instance is the one added to the subscriptions list.

Fixes #2355

* chore(publish): 5.1.1

* Ignore coverage

It's 5.5mb that people installing this don't need :)

* feat(AjaxObservable) : support 'PATCH' request type

Add support of the 'PATCH' request type based on the already existing 'PUT' request.

* fix(subscribeToResult): accept array-like as result

Accept array-like as a result to subscribe, so that
Observable.from and operators using subscribeToResult
have identical behaviour.

* chore(ajax.patch): Adds test for ajax.patch

* fix(forkJoin): add type signature for single observable with selector

Add type signature for using forkJoin with single observable as first parameter
and selector function as second parameter, so that typings would not prevent
usage which is permitted and properly handled by operator.

Closes #2347

* feat(webSocket): Add binaryType to config object

Add binaryType to config object, so that it is possible
to set that parameter on underlying socket before any
data emits happen.

Closes #2353

* fix(merge): return Observable when called with single lowerCaseO

Return Observable when merge is called with single lower case observable,
so that merge would always return Observable instance.

* fix(bindNodeCallback): emit undefined when callback has no success arguments

Emit undefined insteady of empty array by resulting Observable,
when callback function is called without success parameters.

Closes #2254

* chore(danger): update dangerfile to validate commit message

* chore(*): correctly scope disabled `max-line-length` tslint rule

The max line length is set to 150 in 'tslint.json'. In specific regions, it is
desirable to allow longer lines, so these regions should be wrapped in comments
like the following:

```js
// Max line length enforced here.

/* tslint:disable:max-line-length */
// Max line length NOT enforced here.
/* tslint:enable:max-line-length */   <-- CORRECT

// Max line length enforced here.
```

In many cases, the re-enabling comment incorrectly included `disable` instead of
`enable` (as shown below), which essentially keeps the `max-line-length`
**disabled** for the rest of the file:

```js
// Max line length enforced here.

/* tslint:disable:max-line-length */
// Max line length NOT enforced here.
/* tslint:disable:max-line-length */   <-- INCORRECT

// Max line length NOT enforced here.
```

This commit fixes these comments, so the `max-line-length` rule is properly
enforced in regions that don't need longer lines.

* fix(bindCallback): emit undefined when callback is without arguments

In resulting Observable emit undefined when callback is called without
parameters, instead of emitting empty array.

* fix(mergeAll): introduce variant support <T, R> for mergeMap

- closes #2372

* feat(windowTime): maxWindowSize parameter in windowTime operator

Adds new parameter in windowTime operator to control how much values given
window can emit.

Closes #1301

* docs(ObservableInput): add ObservableInput and SubscribableOrPromise descriptions

Add ObservableInput and SubscribableOrPromise interface descriptions,
as well as link these interfaces in type descriptions of operators,
so that users always know what kind of parameters they can pass to
used methods.

* fix(timeoutWith): update timeoutWith to work with new Subscriber leak fix changes
@lock
Copy link

lock bot commented Jun 6, 2018

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.

@lock lock bot locked as resolved and limited conversation to collaborators Jun 6, 2018
Sign up for free to subscribe to this conversation on GitHub. Already have an account? Sign in.
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants