lib: implement finished for webstreams

Refs: nodejs#39316

lib/internal/streams/end-of-stream.js

@@ -38,6 +38,18 @@ const {
   willEmitClose: _willEmitClose,
 } = require('internal/streams/utils');
 
+const Readable = require('internal/streams/readable');
+const Writable = require('internal/streams/writable');
+
+const {
+  isBrandCheck,
+} = require('internal/webstreams/util');
+
+const isReadableStream =
+  isBrandCheck('ReadableStream');
+const isWritableStream =
+  isBrandCheck('WritableStream');
+
 function isRequest(stream) {
   return stream.setHeader && typeof stream.abort === 'function';
 }
@@ -58,14 +70,17 @@ function eos(stream, options, callback) {
 
   callback = once(callback);
 
-  const readable = options.readable ?? isReadableNodeStream(stream);
-  const writable = options.writable ?? isWritableNodeStream(stream);
-
   if (!isNodeStream(stream)) {
-    // TODO: Webstreams.
-    throw new ERR_INVALID_ARG_TYPE('stream', 'Stream', stream);
+    if (isReadableStream(stream)) {
+      stream = Readable.fromWeb(stream);
+    } else if (isWritableStream(stream)) {
+      stream = Writable.fromWeb(stream);
+    }
   }
 
+  const readable = options.readable ?? isReadableNodeStream(stream);
+  const writable = options.writable ?? isWritableNodeStream(stream);
+
   const wState = stream._writableState;
   const rState = stream._readableState;
 

test/parallel/test-webstreams-finished.js

@@ -0,0 +1,17 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const { ReadableStream, WritableStream } = require('stream/web');
+const { finished } = require('stream');
+
+{
+  const rs = new ReadableStream({
+    start(controller) {
+      controller.enqueue('asd');
+    },
+  });
+  finished(rs, common.mustCall(() => {
+
+  }));
+}