From 14ed4ffde938a95cd8947b69b25bb05973733cc3 Mon Sep 17 00:00:00 2001
From: Alisue <lambdalisue@hashnote.net>
Date: Sun, 13 Jun 2021 22:14:46 +0900
Subject: [PATCH] Use Uint8Array as-is to improve performance

Close #3

Note that this package supports Deno v1.10 or over from this commit.

https://deno.com/blog/v1.10#worker.postmessage-supports-structured-clone-algorithm
---
 README.md      |  9 +++++++--
 reader.ts      |  2 +-
 reader_test.ts | 12 ++++++------
 types.ts       |  2 +-
 writer.ts      |  5 +----
 writer_test.ts |  6 +++---
 6 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/README.md b/README.md
index 464cd97..b05e6c2 100644
--- a/README.md
+++ b/README.md
@@ -7,8 +7,13 @@
 [Deno][deno] module to translate Worker's system of messages into
 [Reader][reader] and [Writer][writer].
 
-Note that `WorkerReader` and `WorkerWriter` access `Deno` namespace thus
-[Using Deno in worker](https://deno.land/manual@v1.7.5/runtime/workers#using-deno-in-worker)
+Note that this package requires
+[`Worker.postMessage` supports structured clone
+algorithm](https://deno.com/blog/v1.10#worker.postmessage-supports-structured-clone-algorithm)
+introduced in Deno v1.10.
+
+Note that this package accesses `Deno` namespace thus
+[Using Deno in worker](https://deno.land/manual@v1.11.0/runtime/workers#using-deno-in-worker)
 must be enabled.
 
 [deno]: https://deno.land/
diff --git a/reader.ts b/reader.ts
index 8cf4041..a4c271d 100644
--- a/reader.ts
+++ b/reader.ts
@@ -16,7 +16,7 @@ export class WorkerReader implements Deno.Reader, Deno.Closer {
     this.#worker = worker;
     this.#worker.onmessage = (e) => {
       if (this.#queue && !this.#closed) {
-        this.#queue.put_nowait(new Uint8Array(e.data));
+        this.#queue.put_nowait(e.data);
       }
     };
   }
diff --git a/reader_test.ts b/reader_test.ts
index e4ecbb9..5fbdcf8 100644
--- a/reader_test.ts
+++ b/reader_test.ts
@@ -12,13 +12,13 @@ Deno.test(
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [0, 1, 2, 3, 4],
+        data: new Uint8Array([0, 1, 2, 3, 4]),
       }),
     );
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [5, 6, 7, 8, 9],
+        data: new Uint8Array([5, 6, 7, 8, 9]),
       }),
     );
     let p: Uint8Array;
@@ -45,14 +45,14 @@ Deno.test(
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [0, 1, 2, 3, 4],
+        data: new Uint8Array([0, 1, 2, 3, 4]),
       }),
     );
     reader.close();
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [5, 6, 7, 8, 9],
+        data: new Uint8Array([5, 6, 7, 8, 9]),
       }),
     );
     let p: Uint8Array;
@@ -78,14 +78,14 @@ Deno.test(
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+        data: new Uint8Array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]),
       }),
     );
     reader.close();
     worker.onmessage?.call(
       worker,
       new MessageEvent("worker", {
-        data: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+        data: new Uint8Array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]),
       }),
     );
     let n: number | null;
diff --git a/types.ts b/types.ts
index 19ea774..88b6d40 100644
--- a/types.ts
+++ b/types.ts
@@ -1,4 +1,4 @@
-type Payload = number[];
+type Payload = Uint8Array;
 
 export type WorkerForWorkerReader = {
   onmessage?: (message: MessageEvent<Payload>) => void;
diff --git a/writer.ts b/writer.ts
index 4597582..360c277 100644
--- a/writer.ts
+++ b/writer.ts
@@ -16,10 +16,7 @@ export class WorkerWriter implements Deno.Writer {
    * https://github.com/lambdalisue/deno-workerio/issues/5
    */
   write(p: Uint8Array): Promise<number> {
-    // XXX
-    // Send 'p' as-is once the issue below has resolved.
-    // https://github.com/denoland/deno/issues/3557
-    this.#worker.postMessage(Array.from(p));
+    this.#worker.postMessage(p);
     return Promise.resolve(p.length);
   }
 }
diff --git a/writer_test.ts b/writer_test.ts
index 038b7f3..7b4c434 100644
--- a/writer_test.ts
+++ b/writer_test.ts
@@ -4,7 +4,7 @@ import { WorkerForWorkerWriter, WorkerWriter } from "./mod.ts";
 Deno.test(
   "WorkerWriter invokes internal worker.postMessage when data is written by 'write' method",
   async () => {
-    const posted: number[][] = [];
+    const posted: Uint8Array[] = [];
     const worker: WorkerForWorkerWriter = {
       postMessage(message) {
         posted.push(message);
@@ -13,7 +13,7 @@ Deno.test(
     const writer = new WorkerWriter(worker);
     await writer.write(new Uint8Array([0, 1, 2, 3, 4]));
     await writer.write(new Uint8Array([5, 6, 7, 8, 9]));
-    assertEquals(posted[0], [0, 1, 2, 3, 4]);
-    assertEquals(posted[1], [5, 6, 7, 8, 9]);
+    assertEquals(posted[0], new Uint8Array([0, 1, 2, 3, 4]));
+    assertEquals(posted[1], new Uint8Array([5, 6, 7, 8, 9]));
   },
 );