feat(std/node): consistent Node.js builtin shapes (#8274)

1 files changed, 4 insertions, 299 deletions

diff --git a/std/node/string_decoder.ts b/std/node/string_decoder.ts
index ce7c19538..cc6fb5186 100644
--- a/std/node/string_decoder.ts
+++ b/std/node/string_decoder.ts
@@ -1,299 +1,4 @@
-// Copyright Joyent, Inc. and other Node contributors.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a
-// copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to permit
-// persons to whom the Software is furnished to do so, subject to the
-// following conditions:
-//
-// The above copyright notice and this permission notice shall be included
-// in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
-// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
-// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
-// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
-// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-import { Buffer } from "./buffer.ts";
-import { normalizeEncoding as castEncoding, notImplemented } from "./_utils.ts";
-
-enum NotImplemented {
-  "ascii",
-  "latin1",
-  "utf16le",
-}
-
-function normalizeEncoding(enc?: string): string {
-  const encoding = castEncoding(enc ?? null);
-  if (encoding && encoding in NotImplemented) notImplemented(encoding);
-  if (!encoding && typeof enc === "string" && enc.toLowerCase() !== "raw") {
-    throw new Error(`Unknown encoding: ${enc}`);
-  }
-  return String(encoding);
-}
-/*
- * Checks the type of a UTF-8 byte, whether it's ASCII, a leading byte, or a
- * continuation byte. If an invalid byte is detected, -2 is returned.
- * */
-function utf8CheckByte(byte: number): number {
-  if (byte <= 0x7f) return 0;
-  else if (byte >> 5 === 0x06) return 2;
-  else if (byte >> 4 === 0x0e) return 3;
-  else if (byte >> 3 === 0x1e) return 4;
-  return byte >> 6 === 0x02 ? -1 : -2;
-}
-
-/*
- * Checks at most 3 bytes at the end of a Buffer in order to detect an
- * incomplete multi-byte UTF-8 character. The total number of bytes (2, 3, or 4)
- * needed to complete the UTF-8 character (if applicable) are returned.
- * */
-function utf8CheckIncomplete(
-  self: StringDecoderBase,
-  buf: Buffer,
-  i: number,
-): number {
-  let j = buf.length - 1;
-  if (j < i) return 0;
-  let nb = utf8CheckByte(buf[j]);
-  if (nb >= 0) {
-    if (nb > 0) self.lastNeed = nb - 1;
-    return nb;
-  }
-  if (--j < i || nb === -2) return 0;
-  nb = utf8CheckByte(buf[j]);
-  if (nb >= 0) {
-    if (nb > 0) self.lastNeed = nb - 2;
-    return nb;
-  }
-  if (--j < i || nb === -2) return 0;
-  nb = utf8CheckByte(buf[j]);
-  if (nb >= 0) {
-    if (nb > 0) {
-      if (nb === 2) nb = 0;
-      else self.lastNeed = nb - 3;
-    }
-    return nb;
-  }
-  return 0;
-}
-
-/*
- * Validates as many continuation bytes for a multi-byte UTF-8 character as
- * needed or are available. If we see a non-continuation byte where we expect
- * one, we "replace" the validated continuation bytes we've seen so far with
- * a single UTF-8 replacement character ('\ufffd'), to match v8's UTF-8 decoding
- * behavior. The continuation byte check is included three times in the case
- * where all of the continuation bytes for a character exist in the same buffer.
- * It is also done this way as a slight performance increase instead of using a
- * loop.
- * */
-function utf8CheckExtraBytes(
-  self: StringDecoderBase,
-  buf: Buffer,
-): string | undefined {
-  if ((buf[0] & 0xc0) !== 0x80) {
-    self.lastNeed = 0;
-    return "\ufffd";
-  }
-  if (self.lastNeed > 1 && buf.length > 1) {
-    if ((buf[1] & 0xc0) !== 0x80) {
-      self.lastNeed = 1;
-      return "\ufffd";
-    }
-    if (self.lastNeed > 2 && buf.length > 2) {
-      if ((buf[2] & 0xc0) !== 0x80) {
-        self.lastNeed = 2;
-        return "\ufffd";
-      }
-    }
-  }
-}
-
-/*
- * Attempts to complete a multi-byte UTF-8 character using bytes from a Buffer.
- * */
-function utf8FillLastComplete(
-  this: StringDecoderBase,
-  buf: Buffer,
-): string | undefined {
-  const p = this.lastTotal - this.lastNeed;
-  const r = utf8CheckExtraBytes(this, buf);
-  if (r !== undefined) return r;
-  if (this.lastNeed <= buf.length) {
-    buf.copy(this.lastChar, p, 0, this.lastNeed);
-    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
-  }
-  buf.copy(this.lastChar, p, 0, buf.length);
-  this.lastNeed -= buf.length;
-}
-
-/*
- * Attempts to complete a partial non-UTF-8 character using bytes from a Buffer
- * */
-function utf8FillLastIncomplete(
-  this: StringDecoderBase,
-  buf: Buffer,
-): string | undefined {
-  if (this.lastNeed <= buf.length) {
-    buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, this.lastNeed);
-    return this.lastChar.toString(this.encoding, 0, this.lastTotal);
-  }
-  buf.copy(this.lastChar, this.lastTotal - this.lastNeed, 0, buf.length);
-  this.lastNeed -= buf.length;
-}
-
-/*
- * Returns all complete UTF-8 characters in a Buffer. If the Buffer ended on a
- * partial character, the character's bytes are buffered until the required
- * number of bytes are available.
- * */
-function utf8Text(this: StringDecoderBase, buf: Buffer, i: number): string {
-  const total = utf8CheckIncomplete(this, buf, i);
-  if (!this.lastNeed) return buf.toString("utf8", i);
-  this.lastTotal = total;
-  const end = buf.length - (total - this.lastNeed);
-  buf.copy(this.lastChar, 0, end);
-  return buf.toString("utf8", i, end);
-}
-
-/*
- * For UTF-8, a replacement character is added when ending on a partial
- * character.
- * */
-function utf8End(this: Utf8Decoder, buf?: Buffer): string {
-  const r = buf && buf.length ? this.write(buf) : "";
-  if (this.lastNeed) return r + "\ufffd";
-  return r;
-}
-
-function utf8Write(this: Utf8Decoder | Base64Decoder, buf: Buffer): string {
-  if (buf.length === 0) return "";
-  let r;
-  let i;
-  if (this.lastNeed) {
-    r = this.fillLast(buf);
-    if (r === undefined) return "";
-    i = this.lastNeed;
-    this.lastNeed = 0;
-  } else {
-    i = 0;
-  }
-  if (i < buf.length) return r ? r + this.text(buf, i) : this.text(buf, i);
-  return r || "";
-}
-
-function base64Text(this: StringDecoderBase, buf: Buffer, i: number): string {
-  const n = (buf.length - i) % 3;
-  if (n === 0) return buf.toString("base64", i);
-  this.lastNeed = 3 - n;
-  this.lastTotal = 3;
-  if (n === 1) {
-    this.lastChar[0] = buf[buf.length - 1];
-  } else {
-    this.lastChar[0] = buf[buf.length - 2];
-    this.lastChar[1] = buf[buf.length - 1];
-  }
-  return buf.toString("base64", i, buf.length - n);
-}
-
-function base64End(this: Base64Decoder, buf?: Buffer): string {
-  const r = buf && buf.length ? this.write(buf) : "";
-  if (this.lastNeed) {
-    return r + this.lastChar.toString("base64", 0, 3 - this.lastNeed);
-  }
-  return r;
-}
-
-function simpleWrite(this: StringDecoderBase, buf: Buffer): string {
-  return buf.toString(this.encoding);
-}
-
-function simpleEnd(this: GenericDecoder, buf?: Buffer): string {
-  return buf && buf.length ? this.write(buf) : "";
-}
-
-class StringDecoderBase {
-  public lastChar: Buffer;
-  public lastNeed = 0;
-  public lastTotal = 0;
-  constructor(public encoding: string, nb: number) {
-    this.lastChar = Buffer.allocUnsafe(nb);
-  }
-}
-
-class Base64Decoder extends StringDecoderBase {
-  public end = base64End;
-  public fillLast = utf8FillLastIncomplete;
-  public text = base64Text;
-  public write = utf8Write;
-
-  constructor(encoding?: string) {
-    super(normalizeEncoding(encoding), 3);
-  }
-}
-
-class GenericDecoder extends StringDecoderBase {
-  public end = simpleEnd;
-  public fillLast = undefined;
-  public text = utf8Text;
-  public write = simpleWrite;
-
-  constructor(encoding?: string) {
-    super(normalizeEncoding(encoding), 4);
-  }
-}
-
-class Utf8Decoder extends StringDecoderBase {
-  public end = utf8End;
-  public fillLast = utf8FillLastComplete;
-  public text = utf8Text;
-  public write = utf8Write;
-
-  constructor(encoding?: string) {
-    super(normalizeEncoding(encoding), 4);
-  }
-}
-
-/*
- * StringDecoder provides an interface for efficiently splitting a series of
- * buffers into a series of JS strings without breaking apart multi-byte
- * characters.
- * */
-export class StringDecoder {
-  public encoding: string;
-  public end: (buf?: Buffer) => string;
-  public fillLast: ((buf: Buffer) => string | undefined) | undefined;
-  public lastChar: Buffer;
-  public lastNeed: number;
-  public lastTotal: number;
-  public text: (buf: Buffer, n: number) => string;
-  public write: (buf: Buffer) => string;
-
-  constructor(encoding?: string) {
-    let decoder;
-    switch (encoding) {
-      case "utf8":
-        decoder = new Utf8Decoder(encoding);
-        break;
-      case "base64":
-        decoder = new Base64Decoder(encoding);
-        break;
-      default:
-        decoder = new GenericDecoder(encoding);
-    }
-    this.encoding = decoder.encoding;
-    this.end = decoder.end;
-    this.fillLast = decoder.fillLast;
-    this.lastChar = decoder.lastChar;
-    this.lastNeed = decoder.lastNeed;
-    this.lastTotal = decoder.lastTotal;
-    this.text = decoder.text;
-    this.write = decoder.write;
-  }
-}
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+export * from "./_string_decoder.ts";
+import * as m from "./_string_decoder.ts";
+export default m;