stream: add readableEnded

Adds a readableEnded property and improved finished compat with possible
stream-like objects.

PR-URL: https://github.com/nodejs/node/pull/28814
Refs: https://github.com/nodejs/node/issues/28813
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

2 files changed, 42 insertions, 0 deletions

diff --git a/test/parallel/test-stream-finished.js b/test/parallel/test-stream-finished.js
index 329b4ed42b..d6361ea303 100644
--- a/test/parallel/test-stream-finished.js
+++ b/test/parallel/test-stream-finished.js
@@ -3,6 +3,7 @@
 const common = require('../common');
 const { Writable, Readable, Transform, finished } = require('stream');
 const assert = require('assert');
+const EE = require('events');
 const fs = require('fs');
 const { promisify } = require('util');
 
@@ -175,3 +176,11 @@ const { promisify } = require('util');
   rs.push(null);
   rs.resume();
 }
+
+{
+  const streamLike = new EE();
+  streamLike.readableEnded = true;
+  streamLike.readable = true;
+  finished(streamLike, common.mustCall);
+  streamLike.emit('close');
+}
diff --git a/test/parallel/test-stream-readable-ended.js b/test/parallel/test-stream-readable-ended.js
new file mode 100644
index 0000000000..a224c68f04
--- /dev/null
+++ b/test/parallel/test-stream-readable-ended.js
@@ -0,0 +1,33 @@
+'use strict';
+
+const common = require('../common');
+const { Readable } = require('stream');
+const assert = require('assert');
+
+// basic
+{
+  // Find it on Readable.prototype
+  assert(Readable.prototype.hasOwnProperty('readableEnded'));
+}
+
+// event
+{
+  const readable = new Readable();
+
+  readable._read = () => {
+    // The state ended should start in false.
+    assert.strictEqual(readable.readableEnded, false);
+    readable.push('asd');
+    assert.strictEqual(readable.readableEnded, false);
+    readable.push(null);
+    assert.strictEqual(readable.readableEnded, false);
+  };
+
+  readable.on('end', common.mustCall(() => {
+    assert.strictEqual(readable.readableEnded, true);
+  }));
+
+  readable.on('data', common.mustCall(() => {
+    assert.strictEqual(readable.readableEnded, false);
+  }));
+}