[is-stream] introduce typings (#18285)

types/is-stream/index.d.ts

@@ -0,0 +1,18 @@
+// Type definitions for is-stream 1.1
+// Project: https://github.com/sindresorhus/is-stream#readme
+// Definitions by: BendingBender <https://github.com/me>
+// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+
+/// <reference types="node"/>
+import * as stream from "stream";
+
+export = isStream;
+
+declare function isStream(maybeStream: any): maybeStream is stream.Stream;
+
+declare namespace isStream {
+    function writable(maybeWritable: any): maybeWritable is stream.Writable;
+    function readable(maybeReadable: any): maybeReadable is stream.Readable;
+    function duplex(maybeDuplex: any): maybeDuplex is stream.Duplex;
+    function transform(maybeTransform: any): maybeTransform is stream.Transform;
+}

types/is-stream/is-stream-tests.ts

@@ -0,0 +1,24 @@
+import isStream = require('is-stream');
+import * as stream from 'stream';
+
+const anyStream: any = new stream.Stream();
+
+if (isStream(anyStream)) {
+    const justStream: stream.Stream = anyStream;
+}
+
+if (isStream.writable(anyStream)) {
+    const writableStream: stream.Writable = anyStream;
+}
+
+if (isStream.readable(anyStream)) {
+    const readableStream: stream.Readable = anyStream;
+}
+
+if (isStream.duplex(anyStream)) {
+    const duplexStream: stream.Duplex = anyStream;
+}
+
+if (isStream.transform(anyStream)) {
+    const transformStream: stream.Transform = anyStream;
+}

types/is-stream/tsconfig.json

@@ -0,0 +1,22 @@
+{
+    "compilerOptions": {
+        "module": "commonjs",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "baseUrl": "../",
+        "typeRoots": [
+            "../"
+        ],
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "is-stream-tests.ts"
+    ]
+}

types/is-stream/tslint.json

@@ -0,0 +1 @@
+{ "extends": "dtslint/dt.json" }