feat(ext/web): resourceForReadableStream (#20180)

Extracted from fast streams work.

This is a resource wrapper for `ReadableStream`, allowing us to treat
all `ReadableStream` instances as resources, and remove special paths in
both `fetch` and `serve`.

Performance with a ReadableStream response yields ~18% improvement:

```
  return new Response(new ReadableStream({
    start(controller) {
      controller.enqueue(new Uint8Array([104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100]));
      controller.close();
    }
  })
```

This patch:

```
12:36 $ third_party/prebuilt/mac/wrk http://localhost:8080
Running 10s test @ http://localhost:8080
  2 threads and 10 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    99.96us  100.03us   6.65ms   98.84%
    Req/Sec    47.73k     2.43k   51.02k    89.11%
  959308 requests in 10.10s, 117.10MB read
Requests/sec:  94978.71
Transfer/sec:     11.59MB
```

main:

```
Running 10s test @ http://localhost:8080
  2 threads and 10 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency   163.03us  685.51us  19.73ms   99.27%
    Req/Sec    39.50k     3.98k   66.11k    95.52%
  789582 requests in 10.10s, 82.83MB read
Requests/sec:  78182.65
Transfer/sec:      8.20MB
```

1 files changed, 299 insertions, 0 deletions

diff --git a/cli/tests/unit/streams_test.ts b/cli/tests/unit/streams_test.ts
new file mode 100644
index 000000000..4a573c934
--- /dev/null
+++ b/cli/tests/unit/streams_test.ts
@@ -0,0 +1,299 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+import { fail } from "https://deno.land/std@v0.42.0/testing/asserts.ts";
+import { assertEquals, Deferred, deferred } from "./test_util.ts";
+
+const {
+  core,
+  resourceForReadableStream,
+  // @ts-expect-error TypeScript (as of 3.7) does not support indexing namespaces by symbol
+} = Deno[Deno.internal];
+
+const LOREM =
+  "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.";
+
+// Hello world, with optional close
+// deno-lint-ignore no-explicit-any
+function helloWorldStream(close?: boolean, completion?: Deferred<any>) {
+  return new ReadableStream({
+    start(controller) {
+      controller.enqueue("hello, world");
+      if (close == true) {
+        controller.close();
+      }
+    },
+    cancel(reason) {
+      completion?.resolve(reason);
+    },
+  }).pipeThrough(new TextEncoderStream());
+}
+
+// Hello world, with optional close
+function errorStream(type: "string" | "controller" | "TypeError") {
+  return new ReadableStream({
+    start(controller) {
+      controller.enqueue("hello, world");
+    },
+    pull(controller) {
+      if (type == "string") {
+        throw "Uh oh (string)!";
+      }
+      if (type == "TypeError") {
+        throw TypeError("Uh oh (TypeError)!");
+      }
+      controller.error("Uh oh (controller)!");
+    },
+  }).pipeThrough(new TextEncoderStream());
+}
+
+// Long stream with Lorem Ipsum text.
+function longStream() {
+  return new ReadableStream({
+    start(controller) {
+      for (let i = 0; i < 4; i++) {
+        setTimeout(() => {
+          controller.enqueue(LOREM);
+          if (i == 3) {
+            controller.close();
+          }
+        }, i * 100);
+      }
+    },
+  }).pipeThrough(new TextEncoderStream());
+}
+
+// Empty stream, closes either immediately or on a call to pull.
+function emptyStream(onPull: boolean) {
+  return new ReadableStream({
+    start(controller) {
+      if (!onPull) {
+        controller.close();
+      }
+    },
+    pull(controller) {
+      if (onPull) {
+        controller.close();
+      }
+    },
+  }).pipeThrough(new TextEncoderStream());
+}
+
+// Include an empty chunk
+function emptyChunkStream() {
+  return new ReadableStream({
+    start(controller) {
+      controller.enqueue(new Uint8Array([1]));
+      controller.enqueue(new Uint8Array([]));
+      controller.enqueue(new Uint8Array([2]));
+      controller.close();
+    },
+  });
+}
+
+// Creates a stream with the given number of packets, a configurable delay between packets, and a final
+// action (either "Throw" or "Close").
+function makeStreamWithCount(
+  count: number,
+  delay: number,
+  action: "Throw" | "Close",
+): ReadableStream {
+  function doAction(controller: ReadableStreamDefaultController, i: number) {
+    if (i == count) {
+      if (action == "Throw") {
+        controller.error(new Error("Expected error!"));
+      } else {
+        controller.close();
+      }
+    } else {
+      controller.enqueue(String.fromCharCode("a".charCodeAt(0) + i));
+
+      if (delay == 0) {
+        doAction(controller, i + 1);
+      } else {
+        setTimeout(() => doAction(controller, i + 1), delay);
+      }
+    }
+  }
+
+  return new ReadableStream({
+    start(controller) {
+      if (delay == 0) {
+        doAction(controller, 0);
+      } else {
+        setTimeout(() => doAction(controller, 0), delay);
+      }
+    },
+  }).pipeThrough(new TextEncoderStream());
+}
+
+// Normal stream operation
+Deno.test(async function readableStream() {
+  const rid = resourceForReadableStream(helloWorldStream());
+  const buffer = new Uint8Array(1024);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 12);
+  core.ops.op_close(rid);
+});
+
+// Close the stream after reading everything
+Deno.test(async function readableStreamClose() {
+  const cancel = deferred();
+  const rid = resourceForReadableStream(helloWorldStream(false, cancel));
+  const buffer = new Uint8Array(1024);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 12);
+  core.ops.op_close(rid);
+  assertEquals(await cancel, undefined);
+});
+
+// Close the stream without reading everything
+Deno.test(async function readableStreamClosePartialRead() {
+  const cancel = deferred();
+  const rid = resourceForReadableStream(helloWorldStream(false, cancel));
+  const buffer = new Uint8Array(5);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 5);
+  core.ops.op_close(rid);
+  assertEquals(await cancel, undefined);
+});
+
+// Close the stream without reading anything
+Deno.test(async function readableStreamCloseWithoutRead() {
+  const cancel = deferred();
+  const rid = resourceForReadableStream(helloWorldStream(false, cancel));
+  core.ops.op_close(rid);
+  assertEquals(await cancel, undefined);
+});
+
+Deno.test(async function readableStreamPartial() {
+  const rid = resourceForReadableStream(helloWorldStream());
+  const buffer = new Uint8Array(5);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 5);
+  const buffer2 = new Uint8Array(1024);
+  const nread2 = await core.ops.op_read(rid, buffer2);
+  assertEquals(nread2, 7);
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamLongReadAll() {
+  const rid = resourceForReadableStream(longStream());
+  const buffer = await core.ops.op_read_all(rid);
+  assertEquals(buffer.length, LOREM.length * 4);
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamLongByPiece() {
+  const rid = resourceForReadableStream(longStream());
+  let total = 0;
+  for (let i = 0; i < 100; i++) {
+    const length = await core.ops.op_read(rid, new Uint8Array(16));
+    total += length;
+    if (length == 0) {
+      break;
+    }
+  }
+  assertEquals(total, LOREM.length * 4);
+  core.ops.op_close(rid);
+});
+
+for (
+  const type of [
+    "string",
+    "TypeError",
+    "controller",
+  ] as ("string" | "TypeError" | "controller")[]
+) {
+  Deno.test(`readableStreamError_${type}`, async function () {
+    const rid = resourceForReadableStream(errorStream(type));
+    assertEquals(12, await core.ops.op_read(rid, new Uint8Array(16)));
+    try {
+      await core.ops.op_read(rid, new Uint8Array(1));
+      fail();
+    } catch (e) {
+      assertEquals(e.message, `Uh oh (${type})!`);
+    }
+    core.ops.op_close(rid);
+  });
+}
+
+Deno.test(async function readableStreamEmptyOnStart() {
+  const rid = resourceForReadableStream(emptyStream(true));
+  const buffer = new Uint8Array(1024);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 0);
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamEmptyOnPull() {
+  const rid = resourceForReadableStream(emptyStream(false));
+  const buffer = new Uint8Array(1024);
+  const nread = await core.ops.op_read(rid, buffer);
+  assertEquals(nread, 0);
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamEmptyReadAll() {
+  const rid = resourceForReadableStream(emptyStream(false));
+  const buffer = await core.ops.op_read_all(rid);
+  assertEquals(buffer.length, 0);
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamWithEmptyChunk() {
+  const rid = resourceForReadableStream(emptyChunkStream());
+  const buffer = await core.ops.op_read_all(rid);
+  assertEquals(buffer, new Uint8Array([1, 2]));
+  core.ops.op_close(rid);
+});
+
+Deno.test(async function readableStreamWithEmptyChunkOneByOne() {
+  const rid = resourceForReadableStream(emptyChunkStream());
+  assertEquals(1, await core.ops.op_read(rid, new Uint8Array(1)));
+  assertEquals(1, await core.ops.op_read(rid, new Uint8Array(1)));
+  assertEquals(0, await core.ops.op_read(rid, new Uint8Array(1)));
+  core.ops.op_close(rid);
+});
+
+for (const count of [0, 1, 2, 3]) {
+  for (const delay of [0, 1, 10]) {
+    // Creating a stream that errors in start will throw
+    if (delay > 0) {
+      createStreamTest(count, delay, "Throw");
+    }
+    createStreamTest(count, delay, "Close");
+  }
+}
+
+function createStreamTest(
+  count: number,
+  delay: number,
+  action: "Throw" | "Close",
+) {
+  Deno.test(`streamCount${count}Delay${delay}${action}`, async () => {
+    let rid;
+    try {
+      rid = resourceForReadableStream(
+        makeStreamWithCount(count, delay, action),
+      );
+      for (let i = 0; i < count; i++) {
+        const buffer = new Uint8Array(1);
+        await core.ops.op_read(rid, buffer);
+      }
+      if (action == "Throw") {
+        try {
+          const buffer = new Uint8Array(1);
+          assertEquals(1, await core.ops.op_read(rid, buffer));
+          fail();
+        } catch (e) {
+          // We expect this to be thrown
+          assertEquals(e.message, "Expected error!");
+        }
+      } else {
+        const buffer = new Uint8Array(1);
+        assertEquals(0, await core.ops.op_read(rid, buffer));
+      }
+    } finally {
+      core.ops.op_close(rid);
+    }
+  });
+}