1 files changed, 88 insertions, 0 deletions
diff --git a/std/io/ioutil_test.ts b/std/io/ioutil_test.ts
new file mode 100644
index 000000000..97ab244c0
--- /dev/null
+++ b/std/io/ioutil_test.ts
@@ -0,0 +1,88 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+const { Buffer } = Deno;
+type Reader = Deno.Reader;
+import { test } from "../testing/mod.ts";
+import { assertEquals } from "../testing/asserts.ts";
+import {
+  copyN,
+  readInt,
+  readLong,
+  readShort,
+  sliceLongToBytes
+} from "./ioutil.ts";
+import { BufReader } from "./bufio.ts";
+import { stringsReader } from "./util.ts";
+
+class BinaryReader implements Reader {
+  index = 0;
+
+  constructor(private bytes: Uint8Array = new Uint8Array(0)) {}
+
+  async read(p: Uint8Array): Promise<number | Deno.EOF> {
+    p.set(this.bytes.subarray(this.index, p.byteLength));
+    this.index += p.byteLength;
+    return p.byteLength;
+  }
+}
+
+test(async function testReadShort(): Promise<void> {
+  const r = new BinaryReader(new Uint8Array([0x12, 0x34]));
+  const short = await readShort(new BufReader(r));
+  assertEquals(short, 0x1234);
+});
+
+test(async function testReadInt(): Promise<void> {
+  const r = new BinaryReader(new Uint8Array([0x12, 0x34, 0x56, 0x78]));
+  const int = await readInt(new BufReader(r));
+  assertEquals(int, 0x12345678);
+});
+
+test(async function testReadLong(): Promise<void> {
+  const r = new BinaryReader(
+    new Uint8Array([0x00, 0x00, 0x00, 0x78, 0x12, 0x34, 0x56, 0x78])
+  );
+  const long = await readLong(new BufReader(r));
+  assertEquals(long, 0x7812345678);
+});
+
+test(async function testReadLong2(): Promise<void> {
+  const r = new BinaryReader(
+    new Uint8Array([0, 0, 0, 0, 0x12, 0x34, 0x56, 0x78])
+  );
+  const long = await readLong(new BufReader(r));
+  assertEquals(long, 0x12345678);
+});
+
+test(async function testSliceLongToBytes(): Promise<void> {
+  const arr = sliceLongToBytes(0x1234567890abcdef);
+  const actual = readLong(new BufReader(new BinaryReader(new Uint8Array(arr))));
+  const expected = readLong(
+    new BufReader(
+      new BinaryReader(
+        new Uint8Array([0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef])
+      )
+    )
+  );
+  assertEquals(actual, expected);
+});
+
+test(async function testSliceLongToBytes2(): Promise<void> {
+  const arr = sliceLongToBytes(0x12345678);
+  assertEquals(arr, [0, 0, 0, 0, 0x12, 0x34, 0x56, 0x78]);
+});
+
+test(async function testCopyN1(): Promise<void> {
+  const w = new Buffer();
+  const r = stringsReader("abcdefghij");
+  const n = await copyN(w, r, 3);
+  assertEquals(n, 3);
+  assertEquals(w.toString(), "abc");
+});
+
+test(async function testCopyN2(): Promise<void> {
+  const w = new Buffer();
+  const r = stringsReader("abcdefghij");
+  const n = await copyN(w, r, 11);
+  assertEquals(n, 10);
+  assertEquals(w.toString(), "abcdefghij");
+});