Emit 'readable' always in the next tick, resulting in a single
call to _read() per microtick. This removes the need for the
user to implement buffering if they wanted to call this.push()
multiple times in an asynchronous fashion, as this.push() triggers
this._read() call.

PR-URL: #17979
Fixes: #3203
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

Fixes a regression introduced by the once-per-microtick 'readable'
event emission.

See: #17979
PR-URL: #18372
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

Fixes a regression introduced by the once-per-microtick 'readable'
event emission.

See: nodejs#17979
PR-URL: nodejs#18372
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

The behaviour of the `'readable'` event changed, or was tightened up,
in

    nodejs/node#17979

such that it is _always_ called on the next tick. This change appears
first in Node.JS v10.0).

Since we rely on `'readable' in the multiplexing, it means that we
have to be more careful about when we wait for the next event loop to
come around in tests.

The tests tend to be much more brittle than live code with respect to
the order things happen, since they attempt to nail down precise
states or orderings (e.g., "the `unpipe` happened exactly between
these writes").

The behaviour of the `'readable'` event changed, or was tightened up,
in

    nodejs/node#17979

such that it is _always_ called on the next tick. This change appears
first in Node.JS v10.0).

Since we rely on `'readable' in the multiplexing, it means that we
have to be more careful about when we wait for the next event loop to
come around in tests.

The tests tend to be much more brittle than live code with respect to
the order things happen, since they attempt to nail down precise
states or orderings (e.g., "the `unpipe` happened exactly between
these writes").

nodejs#17979 introduced a change in the
doc that was not correct about _read always being called asynchronously.
This does not hold true when it is in flowing mode.

See: nodejs#17979
Fixes: nodejs#24919

#17979 introduced a change in the
doc that was not correct about _read always being called asynchronously.
This does not hold true when it is in flowing mode.

See: #17979
Fixes: #24919

PR-URL: #25442
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>

#17979 introduced a change in the
doc that was not correct about _read always being called asynchronously.
This does not hold true when it is in flowing mode.

See: #17979
Fixes: #24919

PR-URL: #25442
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>

nodejs#17979 introduced a change in the
doc that was not correct about _read always being called asynchronously.
This does not hold true when it is in flowing mode.

See: nodejs#17979
Fixes: nodejs#24919

PR-URL: nodejs#25442
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>