chore(node): add Readable.from utility

Added in v12.3.0 from PR nodejs/node#27660

Author: imcotton

types/node/stream.d.ts

@@ -1,3 +1,5 @@
+/// <reference lib="esnext.asynciterable" />
+
 declare module "stream" {
     import * as events from "events";
 
@@ -18,6 +20,7 @@ declare module "stream" {
         }
 
         class Readable extends Stream implements NodeJS.ReadableStream {
+            static from(iterable: Iterable<any> | AsyncIterable<any>, opts?: ReadableOptions): NodeJS.ReadableStream;
             readable: boolean;
             readonly readableHighWaterMark: number;
             readonly readableLength: number;

types/node/test/stream.ts

@@ -192,3 +192,17 @@ function stream_readable_pipe_test() {
     z.close();
     rs.close();
 }
+
+async function readable_from() {
+    const list = [ 1, 2, 3 ];
+    const listPromise = list.map(n => Promise.resolve(n));
+
+    const readableSync = Readable.from(list);
+    const readableAsync = Readable.from(listPromise);
+
+    let i = 0;
+    readableSync.on('data', n => assert(n === list[i++]));
+
+    let j = 0;
+    readableAsync.on('data', n => assert(n === list[j++]));
+}

types/readable-stream/package.json

@@ -1,6 +1,7 @@
 {
     "private": true,
     "dependencies": {
+        "@types/node": "10.x",
         "safe-buffer": "*"
     }
 }