stream: duplexify

PR-URL: https://github.com/nodejs/node/pull/39519
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/doc/api/stream.md b/doc/api/stream.md
index 312f200e61c..047e1687d2e 100644
--- a/doc/api/stream.md
+++ b/doc/api/stream.md
@@ -2081,6 +2081,34 @@ added: REPLACEME
 * `streamWritable` {stream.Writable}
 * Returns: {WritableStream}
 
+### `stream.Duplex.from(src)`
+<!-- YAML
+added: REPLACEME
+-->
+
+* `src` {Stream|Blob|ArrayBuffer|string|Iterable|AsyncIterable|
+  AsyncGeneratorFunction|AsyncFunction|Promise|Object}
+
+A utility method for creating duplex streams.
+
+* `Stream` converts writable stream into writable `Duplex` and readable stream
+  to `Duplex`.
+* `Blob` converts into readable `Duplex`.
+* `string` converts into readable `Duplex`.
+* `ArrayBuffer` converts into readable `Duplex`.
+* `AsyncIterable` converts into a readable `Duplex`. Cannot yield
+  `null`.
+* `AsyncGeneratorFunction` converts into a readable/writable transform
+  `Duplex`. Must take a source `AsyncIterable` as first parameter. Cannot yield
+  `null`.
+* `AsyncFunction` converts into a writable `Duplex`. Must return
+  either `null` or `undefined`
+* `Object ({ writable, readable })` converts `readable` and
+  `writable` into `Stream` and then combines them into `Duplex` where the
+  `Duplex` will write to the `writable` and read from the `readable`.
+* `Promise` converts into readable `Duplex`. Value `null` is ignored.
+* Returns: {stream.Duplex}
+
 ### `stream.Duplex.fromWeb(pair[, options])`
 <!-- YAML
 added: REPLACEME