fix(streams): reject string in ReadableStream.from type (#25116)

WebIDL `async iterable<T>` type rejects `string`

Ref whatwg/webidl#1397, #24623

Author: petamoriken

cli/tsc/dts/lib.dom.d.ts

@@ -18277,7 +18277,7 @@ declare var ReadableStream: {
     new(underlyingSource: UnderlyingByteSource, strategy?: { highWaterMark?: number }): ReadableStream<Uint8Array>;
     new<R = any>(underlyingSource: UnderlyingDefaultSource<R>, strategy?: QueuingStrategy<R>): ReadableStream<R>;
     new<R = any>(underlyingSource?: UnderlyingSource<R>, strategy?: QueuingStrategy<R>): ReadableStream<R>;
-    from<R>(asyncIterable: AsyncIterable<R> | Iterable<R | PromiseLike<R>>): ReadableStream<R>;
+    from<R>(asyncIterable: AsyncIterable<R> | Iterable<R | PromiseLike<R>> & object): ReadableStream<R>;
 };
 
 /** [MDN Reference](https://developer.mozilla.org/docs/Web/API/ReadableStreamBYOBReader) */

ext/web/06_streams.js

@@ -2922,7 +2922,7 @@ function readableStreamPipeTo(
 }
 
 /**
- * @param {ReadableStreamGenericReader<any> | ReadableStreamBYOBReader} reader
+ * @param {ReadableStreamGenericReader | ReadableStreamBYOBReader} reader
  * @param {any} reason
  * @returns {Promise<void>}
  */
@@ -2955,7 +2955,7 @@ function readableStreamReaderGenericInitialize(reader, stream) {
 
 /**
  * @template R
- * @param {ReadableStreamGenericReader<R> | ReadableStreamBYOBReader} reader
+ * @param {ReadableStreamGenericReader | ReadableStreamBYOBReader} reader
  */
 function readableStreamReaderGenericRelease(reader) {
   const stream = reader[_stream];

ext/web/06_streams_types.d.ts

@@ -60,8 +60,8 @@ interface VoidFunction {
   (): void;
 }
 
-interface ReadableStreamGenericReader<T> {
-  readonly closed: Promise<void>;
+interface ReadableStreamGenericReader {
+  readonly closed: Promise<undefined>;
   // deno-lint-ignore no-explicit-any
   cancel(reason?: any): Promise<void>;
 }

ext/web/lib.deno_web.d.ts

@@ -882,7 +882,7 @@ declare var ReadableStream: {
     strategy?: QueuingStrategy<R>,
   ): ReadableStream<R>;
   from<R>(
-    asyncIterable: AsyncIterable<R> | Iterable<R | PromiseLike<R>>,
+    asyncIterable: AsyncIterable<R> | Iterable<R | PromiseLike<R>> & object,
   ): ReadableStream<R>;
 };
 

tests/specs/check/reject_string_in_readable_stream_from/__test__.jsonc

@@ -0,0 +1,5 @@
+{
+  "args": "check ./main.ts",
+  "output": "main.out",
+  "exitCode": 1
+}

tests/specs/check/reject_string_in_readable_stream_from/main.out

@@ -0,0 +1,5 @@
+Check [WILDCARD]/main.ts
+error: TS2345 [ERROR]: Argument of type 'string' is not assignable to parameter of type 'AsyncIterable<string> | (Iterable<string | PromiseLike<string>> & object)'.
+ReadableStream.from("string");
+                    ~~~~~~~~
+    at [WILDCARD]/main.ts:1:21

tests/specs/check/reject_string_in_readable_stream_from/main.ts

@@ -0,0 +1 @@
+ReadableStream.from("string");

tests/unit/streams_test.ts

@@ -541,6 +541,7 @@ Deno.test(async function decompressionStreamInvalidGzipStillReported() {
 
 Deno.test(function readableStreamFromWithStringThrows() {
   assertThrows(
+    // @ts-expect-error: primitives are not acceptable
     () => ReadableStream.from("string"),
     TypeError,
     "Failed to execute 'ReadableStream.from': Argument 1 can not be converted to async iterable.",