multipart limits values to one in pipe

Problem: When using use(multipart$()), I can’t seem to expand the Observable with additional values beyond the multipart upload. For example:

const a$ = r.pipe(
    r.matchPath('a'),
    r.matchType('POST'),
    r.useEffect(Rx.pipe(
        use(multipart$()),
        // Expanding the Observables with additional values.
        Ro.combineLatest(Rx.from([1, 2, 3])),
        // Seems to only log once, apparently the last value in above array.
        Ro.tap(([upload, n]) => console.log(n)),
        Ro.count(),
        // Responds with 1. Should be 3.
        Ro.map(body => ({status: 200, body})),
    )),
)

I created a repository to reproduce the issue: https://github.com/tstelzer/marble-playground

node: v13.2.0 “@marblejs/core”: “^3.0.0-next.78”, “@marblejs/middleware-body”: “^3.0.0-next.78”, “@marblejs/middleware-cors”: “^3.0.0-next.78”, “@marblejs/middleware-io”: “^3.0.0-next.78”, “@marblejs/middleware-logger”: “^3.0.0-next.78”, “@marblejs/middleware-multipart”: “^3.0.0-next.78”, “rxjs”: “^6.5.3”

[JozefFlakus]

@tstelzer I’ve spotted one issue in your code. There is a big difference between:

    // ...
    r.useEffect(pipe(
       // ...
    )),

and

    // ...
    r.useEffect(req$ => req$.pipe(
       // ...
    )),

Take a look at the RxJS pipe source code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/util/pipe.ts

Marble.js effect is a function with two parameters - not only one. Which results with passing both req$ and ctx to the pipe.

After the fix the a$ count() returns 0 but I need to futher investigate why.

EDIT: I found the bug that was introduced with rc.2 (rc.1 forks fine).

[JozefFlakus]

v3.0.0-rc.3 released