1 files changed, 53 insertions, 0 deletions
diff --git a/ext/node/polyfills/internal/streams/lazy_transform.mjs b/ext/node/polyfills/internal/streams/lazy_transform.mjs
new file mode 100644
index 000000000..2bb93bd91
--- /dev/null
+++ b/ext/node/polyfills/internal/streams/lazy_transform.mjs
@@ -0,0 +1,53 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+// Copyright Joyent and Node contributors. All rights reserved. MIT license.
+// deno-lint-ignore-file
+
+import { getDefaultEncoding } from "internal:deno_node/polyfills/internal/crypto/util.ts";
+import stream from "internal:deno_node/polyfills/stream.ts";
+
+function LazyTransform(options) {
+  this._options = options;
+}
+Object.setPrototypeOf(LazyTransform.prototype, stream.Transform.prototype);
+Object.setPrototypeOf(LazyTransform, stream.Transform);
+
+function makeGetter(name) {
+  return function () {
+    stream.Transform.call(this, this._options);
+    this._writableState.decodeStrings = false;
+
+    if (!this._options || !this._options.defaultEncoding) {
+      this._writableState.defaultEncoding = getDefaultEncoding();
+    }
+
+    return this[name];
+  };
+}
+
+function makeSetter(name) {
+  return function (val) {
+    Object.defineProperty(this, name, {
+      value: val,
+      enumerable: true,
+      configurable: true,
+      writable: true,
+    });
+  };
+}
+
+Object.defineProperties(LazyTransform.prototype, {
+  _readableState: {
+    get: makeGetter("_readableState"),
+    set: makeSetter("_readableState"),
+    configurable: true,
+    enumerable: true,
+  },
+  _writableState: {
+    get: makeGetter("_writableState"),
+    set: makeSetter("_writableState"),
+    configurable: true,
+    enumerable: true,
+  },
+});
+
+export default LazyTransform;