From f0ba11cd23aeef62170cf178bd3c060659bd1072 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 21 May 2026 15:18:41 +0000
Subject: [PATCH 1/2] Initial plan


From 921d20d289802a778ccb9b4b53c924f00fb95e0a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 21 May 2026 15:34:36 +0000
Subject: [PATCH 2/2] Fix RLC bytes body type for browser builds

Agent-Logs-Url: https://github.com/Azure/autorest.typescript/sessions/2adb414c-3c36-49bb-9665-00c57e6b3390

Co-authored-by: siddharth9606 <199754214+siddharth9606@users.noreply.github.com>
---
 packages/typespec-ts/src/utils/modelUtils.ts  |  2 +-
 .../test/unit/bytesGenerator.spec.ts          | 36 ++++++++++---------
 2 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/packages/typespec-ts/src/utils/modelUtils.ts b/packages/typespec-ts/src/utils/modelUtils.ts
index 71cbcebf46..2ce6eb17d9 100644
--- a/packages/typespec-ts/src/utils/modelUtils.ts
+++ b/packages/typespec-ts/src/utils/modelUtils.ts
@@ -85,7 +85,7 @@ import { getModelNamespaceName } from "./namespaceUtils.js";
 import { reportDiagnostic } from "../lib.js";
 
 export const BINARY_TYPE_UNION =
-  "string | Uint8Array | ReadableStream<Uint8Array> | NodeJS.ReadableStream";
+  "string | Uint8Array | ReadableStream<Uint8Array> | AsyncIterable<Uint8Array>";
 
 export const BINARY_AND_FILE_TYPE_UNION = `${BINARY_TYPE_UNION} | File`;
 
diff --git a/packages/typespec-ts/test/unit/bytesGenerator.spec.ts b/packages/typespec-ts/test/unit/bytesGenerator.spec.ts
index f459556b09..703a658478 100644
--- a/packages/typespec-ts/test/unit/bytesGenerator.spec.ts
+++ b/packages/typespec-ts/test/unit/bytesGenerator.spec.ts
@@ -30,7 +30,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream;
+              | AsyncIterable<Uint8Array>;
             }
             
             export interface UploadFileViaBodyMediaTypesParam {
@@ -66,7 +66,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream;
+              | AsyncIterable<Uint8Array>;
             }
             
             export interface UploadFileViaBodyMediaTypesParam {
@@ -125,7 +125,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream;
+              | AsyncIterable<Uint8Array>;
           }
           
           export type ReadParameters = ReadBodyParam & RequestParameters;
@@ -201,7 +201,7 @@ describe("bytes", () => {
                           | string
                           | Uint8Array
                           | ReadableStream<Uint8Array>
-                          | NodeJS.ReadableStream
+                          | AsyncIterable<Uint8Array>
                           | File;
                         filename?: string;
                         contentType?: string;
@@ -212,7 +212,7 @@ describe("bytes", () => {
                           | string
                           | Uint8Array
                           | ReadableStream<Uint8Array>
-                          | NodeJS.ReadableStream
+                          | AsyncIterable<Uint8Array>
                           | File;
                         filename?: string;
                         contentType?: string;
@@ -263,7 +263,7 @@ describe("bytes", () => {
                           | string
                           | Uint8Array
                           | ReadableStream<Uint8Array>
-                          | NodeJS.ReadableStream
+                          | AsyncIterable<Uint8Array>
                           | File;
                         filename?: string;
                         contentType?: string;
@@ -274,7 +274,7 @@ describe("bytes", () => {
                           | string
                           | Uint8Array
                           | ReadableStream<Uint8Array>
-                          | NodeJS.ReadableStream
+                          | AsyncIterable<Uint8Array>
                           | File;
                         filename?: string;
                         contentType?: string;
@@ -370,7 +370,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream
+              | AsyncIterable<Uint8Array>
               | File;
             filename?: string;
             contentType?: string;
@@ -382,7 +382,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream
+              | AsyncIterable<Uint8Array>
               | File;
             filename?: string;
             contentType?: string;
@@ -391,11 +391,13 @@ describe("bytes", () => {
           export interface FooFilesPartDescriptor {
             name: "files";
             body:
-              | string
-              | Uint8Array
-              | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream
-              | File;
+              | (
+                  | string
+                  | Uint8Array
+                  | ReadableStream<Uint8Array>
+                  | AsyncIterable<Uint8Array>
+                  | File
+                )[];
             filename?: string;
             contentType?: string;
           }
@@ -406,7 +408,7 @@ describe("bytes", () => {
               | string
               | Uint8Array
               | ReadableStream<Uint8Array>
-              | NodeJS.ReadableStream
+              | AsyncIterable<Uint8Array>
               | File
               | number;
             filename?: string;
@@ -528,7 +530,7 @@ describe("bytes", () => {
 
       export interface ReadBodyParam {
         /** Value may contain any sequence of octets */
-        body: string | Uint8Array | ReadableStream<Uint8Array> | NodeJS.ReadableStream;
+        body: string | Uint8Array | ReadableStream<Uint8Array> | AsyncIterable<Uint8Array>;
       }
 
       export interface ReadMediaTypesParam {
@@ -559,7 +561,7 @@ describe("bytes", () => {
           | string
           | Uint8Array
           | ReadableStream<Uint8Array>
-          | NodeJS.ReadableStream;
+          | AsyncIterable<Uint8Array>;
         }
         
         export interface ReadMediaTypesParam {