1 files changed, 296 insertions, 0 deletions
diff --git a/cli/js/tests/buffer_test.ts b/cli/js/tests/buffer_test.ts
new file mode 100644
index 000000000..163ed0a30
--- /dev/null
+++ b/cli/js/tests/buffer_test.ts
@@ -0,0 +1,296 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+// This code has been ported almost directly from Go's src/bytes/buffer_test.go
+// Copyright 2009 The Go Authors. All rights reserved. BSD license.
+// https://github.com/golang/go/blob/master/LICENSE
+import {
+  assertEquals,
+  assert,
+  assertStrContains,
+  unitTest
+} from "./test_util.ts";
+
+const { Buffer, readAll, readAllSync, writeAll, writeAllSync } = Deno;
+type Buffer = Deno.Buffer;
+
+// N controls how many iterations of certain checks are performed.
+const N = 100;
+let testBytes: Uint8Array | null;
+let testString: string | null;
+
+function init(): void {
+  if (testBytes == null) {
+    testBytes = new Uint8Array(N);
+    for (let i = 0; i < N; i++) {
+      testBytes[i] = "a".charCodeAt(0) + (i % 26);
+    }
+    const decoder = new TextDecoder();
+    testString = decoder.decode(testBytes);
+  }
+}
+
+function check(buf: Deno.Buffer, s: string): void {
+  const bytes = buf.bytes();
+  assertEquals(buf.length, bytes.byteLength);
+  const decoder = new TextDecoder();
+  const bytesStr = decoder.decode(bytes);
+  assertEquals(bytesStr, s);
+  assertEquals(buf.length, buf.toString().length);
+  assertEquals(buf.length, s.length);
+}
+
+// Fill buf through n writes of byte slice fub.
+// The initial contents of buf corresponds to the string s;
+// the result is the final contents of buf returned as a string.
+async function fillBytes(
+  buf: Buffer,
+  s: string,
+  n: number,
+  fub: Uint8Array
+): Promise<string> {
+  check(buf, s);
+  for (; n > 0; n--) {
+    const m = await buf.write(fub);
+    assertEquals(m, fub.byteLength);
+    const decoder = new TextDecoder();
+    s += decoder.decode(fub);
+    check(buf, s);
+  }
+  return s;
+}
+
+// Empty buf through repeated reads into fub.
+// The initial contents of buf corresponds to the string s.
+async function empty(buf: Buffer, s: string, fub: Uint8Array): Promise<void> {
+  check(buf, s);
+  while (true) {
+    const r = await buf.read(fub);
+    if (r === Deno.EOF) {
+      break;
+    }
+    s = s.slice(r);
+    check(buf, s);
+  }
+  check(buf, "");
+}
+
+function repeat(c: string, bytes: number): Uint8Array {
+  assertEquals(c.length, 1);
+  const ui8 = new Uint8Array(bytes);
+  ui8.fill(c.charCodeAt(0));
+  return ui8;
+}
+
+unitTest(function bufferNewBuffer(): void {
+  init();
+  assert(testBytes);
+  assert(testString);
+  const buf = new Buffer(testBytes.buffer as ArrayBuffer);
+  check(buf, testString);
+});
+
+unitTest(async function bufferBasicOperations(): Promise<void> {
+  init();
+  assert(testBytes);
+  assert(testString);
+  const buf = new Buffer();
+  for (let i = 0; i < 5; i++) {
+    check(buf, "");
+
+    buf.reset();
+    check(buf, "");
+
+    buf.truncate(0);
+    check(buf, "");
+
+    let n = await buf.write(testBytes.subarray(0, 1));
+    assertEquals(n, 1);
+    check(buf, "a");
+
+    n = await buf.write(testBytes.subarray(1, 2));
+    assertEquals(n, 1);
+    check(buf, "ab");
+
+    n = await buf.write(testBytes.subarray(2, 26));
+    assertEquals(n, 24);
+    check(buf, testString.slice(0, 26));
+
+    buf.truncate(26);
+    check(buf, testString.slice(0, 26));
+
+    buf.truncate(20);
+    check(buf, testString.slice(0, 20));
+
+    await empty(buf, testString.slice(0, 20), new Uint8Array(5));
+    await empty(buf, "", new Uint8Array(100));
+
+    // TODO buf.writeByte()
+    // TODO buf.readByte()
+  }
+});
+
+unitTest(async function bufferReadEmptyAtEOF(): Promise<void> {
+  // check that EOF of 'buf' is not reached (even though it's empty) if
+  // results are written to buffer that has 0 length (ie. it can't store any data)
+  const buf = new Buffer();
+  const zeroLengthTmp = new Uint8Array(0);
+  const result = await buf.read(zeroLengthTmp);
+  assertEquals(result, 0);
+});
+
+unitTest(async function bufferLargeByteWrites(): Promise<void> {
+  init();
+  const buf = new Buffer();
+  const limit = 9;
+  for (let i = 3; i < limit; i += 3) {
+    const s = await fillBytes(buf, "", 5, testBytes!);
+    await empty(buf, s, new Uint8Array(Math.floor(testString!.length / i)));
+  }
+  check(buf, "");
+});
+
+unitTest(async function bufferTooLargeByteWrites(): Promise<void> {
+  init();
+  const tmp = new Uint8Array(72);
+  const growLen = Number.MAX_VALUE;
+  const xBytes = repeat("x", 0);
+  const buf = new Buffer(xBytes.buffer as ArrayBuffer);
+  await buf.read(tmp);
+
+  let err;
+  try {
+    buf.grow(growLen);
+  } catch (e) {
+    err = e;
+  }
+
+  assert(err instanceof Error);
+  assertStrContains(err.message, "grown beyond the maximum size");
+});
+
+unitTest(async function bufferLargeByteReads(): Promise<void> {
+  init();
+  assert(testBytes);
+  assert(testString);
+  const buf = new Buffer();
+  for (let i = 3; i < 30; i += 3) {
+    const n = Math.floor(testBytes.byteLength / i);
+    const s = await fillBytes(buf, "", 5, testBytes.subarray(0, n));
+    await empty(buf, s, new Uint8Array(testString.length));
+  }
+  check(buf, "");
+});
+
+unitTest(function bufferCapWithPreallocatedSlice(): void {
+  const buf = new Buffer(new ArrayBuffer(10));
+  assertEquals(buf.capacity, 10);
+});
+
+unitTest(async function bufferReadFrom(): Promise<void> {
+  init();
+  assert(testBytes);
+  assert(testString);
+  const buf = new Buffer();
+  for (let i = 3; i < 30; i += 3) {
+    const s = await fillBytes(
+      buf,
+      "",
+      5,
+      testBytes.subarray(0, Math.floor(testBytes.byteLength / i))
+    );
+    const b = new Buffer();
+    await b.readFrom(buf);
+    const fub = new Uint8Array(testString.length);
+    await empty(b, s, fub);
+  }
+});
+
+unitTest(async function bufferReadFromSync(): Promise<void> {
+  init();
+  assert(testBytes);
+  assert(testString);
+  const buf = new Buffer();
+  for (let i = 3; i < 30; i += 3) {
+    const s = await fillBytes(
+      buf,
+      "",
+      5,
+      testBytes.subarray(0, Math.floor(testBytes.byteLength / i))
+    );
+    const b = new Buffer();
+    b.readFromSync(buf);
+    const fub = new Uint8Array(testString.length);
+    await empty(b, s, fub);
+  }
+});
+
+unitTest(async function bufferTestGrow(): Promise<void> {
+  const tmp = new Uint8Array(72);
+  for (const startLen of [0, 100, 1000, 10000, 100000]) {
+    const xBytes = repeat("x", startLen);
+    for (const growLen of [0, 100, 1000, 10000, 100000]) {
+      const buf = new Buffer(xBytes.buffer as ArrayBuffer);
+      // If we read, this affects buf.off, which is good to test.
+      const result = await buf.read(tmp);
+      const nread = result === Deno.EOF ? 0 : result;
+      buf.grow(growLen);
+      const yBytes = repeat("y", growLen);
+      await buf.write(yBytes);
+      // Check that buffer has correct data.
+      assertEquals(
+        buf.bytes().subarray(0, startLen - nread),
+        xBytes.subarray(nread)
+      );
+      assertEquals(
+        buf.bytes().subarray(startLen - nread, startLen - nread + growLen),
+        yBytes
+      );
+    }
+  }
+});
+
+unitTest(async function testReadAll(): Promise<void> {
+  init();
+  assert(testBytes);
+  const reader = new Buffer(testBytes.buffer as ArrayBuffer);
+  const actualBytes = await readAll(reader);
+  assertEquals(testBytes.byteLength, actualBytes.byteLength);
+  for (let i = 0; i < testBytes.length; ++i) {
+    assertEquals(testBytes[i], actualBytes[i]);
+  }
+});
+
+unitTest(function testReadAllSync(): void {
+  init();
+  assert(testBytes);
+  const reader = new Buffer(testBytes.buffer as ArrayBuffer);
+  const actualBytes = readAllSync(reader);
+  assertEquals(testBytes.byteLength, actualBytes.byteLength);
+  for (let i = 0; i < testBytes.length; ++i) {
+    assertEquals(testBytes[i], actualBytes[i]);
+  }
+});
+
+unitTest(async function testWriteAll(): Promise<void> {
+  init();
+  assert(testBytes);
+  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]);
+  }
+});
+
+unitTest(function testWriteAllSync(): void {
+  init();
+  assert(testBytes);
+  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]);
+  }
+});