feat: expose writeAll() and writeAllSync() (#2298)

Symmetric with `readAll()` and `readAllSync()`. Also used in `xeval`.
Also correct usage in `writeFile()`/`writeFileSync()`.

1 files changed, 23 insertions, 1 deletions

diff --git a/js/buffer_test.ts b/js/buffer_test.ts
index 3b2f5d312..911750bb1 100644
--- a/js/buffer_test.ts
+++ b/js/buffer_test.ts
@@ -5,7 +5,7 @@
 // https://github.com/golang/go/blob/master/LICENSE
 import { assertEquals, test } from "./test_util.ts";
 
-const { Buffer, readAll, readAllSync } = Deno;
+const { Buffer, readAll, readAllSync, writeAll, writeAllSync } = Deno;
 type Buffer = Deno.Buffer;
 
 // N controls how many iterations of certain checks are performed.
@@ -253,3 +253,25 @@ test(function testReadAllSync(): void {
     assertEquals(testBytes[i], actualBytes[i]);
   }
 });
+
+test(async function testWriteAll(): Promise<void> {
+  init();
+  const writer = new Buffer();
+  await writeAll(writer, testBytes);
+  const actualBytes = writer.bytes();
+  assertEquals(testBytes.byteLength, actualBytes.byteLength);
+  for (let i = 0; i < testBytes.length; ++i) {
+    assertEquals(testBytes[i], actualBytes[i]);
+  }
+});
+
+test(function testWriteAllSync(): void {
+  init();
+  const writer = new Buffer();
+  writeAllSync(writer, testBytes);
+  const actualBytes = writer.bytes();
+  assertEquals(testBytes.byteLength, actualBytes.byteLength);
+  for (let i = 0; i < testBytes.length; ++i) {
+    assertEquals(testBytes[i], actualBytes[i]);
+  }
+});