stream: fix finished writable/readable state

writable/readable does not indicate whether as stream is
a Writable/Readable. This implements a better check for
whether a object is a Writable/Readable.

PR-URL: nodejs#31527
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

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

@@ -13,6 +13,18 @@ function isRequest(stream) {
   return stream.setHeader && typeof stream.abort === 'function';
 }
 
+function isReadable(stream) {
+  return typeof stream.readable === 'boolean' ||
+    typeof stream.readableEnded === 'boolean' ||
+    !!stream._readableState;
+}
+
+function isWritable(stream) {
+  return typeof stream.writable === 'boolean' ||
+    typeof stream.writableEnded === 'boolean' ||
+    !!stream._writableState;
+}
+
 function eos(stream, opts, callback) {
   if (arguments.length === 2) {
     callback = opts;
@@ -28,8 +40,10 @@ function eos(stream, opts, callback) {
 
   callback = once(callback);
 
-  let readable = opts.readable || (opts.readable !== false && stream.readable);
-  let writable = opts.writable || (opts.writable !== false && stream.writable);
+  let readable = opts.readable ||
+    (opts.readable !== false && isReadable(stream));
+  let writable = opts.writable ||
+    (opts.writable !== false && isWritable(stream));
 
   const onlegacyfinish = () => {
     if (!stream.writable) onfinish();

test/parallel/test-stream-finished.js

@@ -184,3 +184,21 @@ const { promisify } = require('util');
   finished(streamLike, common.mustCall);
   streamLike.emit('close');
 }
+
+{
+  const writable = new Writable({ write() {} });
+  writable.writable = false;
+  writable.destroy();
+  finished(writable, common.mustCall((err) => {
+    assert.strictEqual(err.code, 'ERR_STREAM_PREMATURE_CLOSE');
+  }));
+}
+
+{
+  const readable = new Readable();
+  readable.readable = false;
+  readable.destroy();
+  finished(readable, common.mustCall((err) => {
+    assert.strictEqual(err.code, 'ERR_STREAM_PREMATURE_CLOSE');
+  }));
+}