feat(ext/node): embed std/node into the snapshot (#17724)

This commit moves "deno_std/node" in "ext/node" crate. The code is
transpiled and snapshotted during the build process.

During the first pass a minimal amount of work was done to create the
snapshot, a lot of code in "ext/node" depends on presence of "Deno"
global. This code will be gradually fixed in the follow up PRs to migrate
it to import relevant APIs from "internal:" modules.

Currently the code from snapshot is not used in any way, and all
Node/npm compatibility still uses code from 
"https://deno.land/std/node" (or from the location specified by 
"DENO_NODE_COMPAT_URL"). This will also be handled in a follow 
up PRs.

---------

Co-authored-by: crowlkats <crowlkats@toaxl.com>
Co-authored-by: Divy Srivastava <dj.srivastava23@gmail.com>
Co-authored-by: Yoshiya Hinosawa <stibium121@gmail.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/ext/node/polyfills/_fs/_fs_readlink.ts b/ext/node/polyfills/_fs/_fs_readlink.ts
new file mode 100644
index 000000000..07d1b6f6f
--- /dev/null
+++ b/ext/node/polyfills/_fs/_fs_readlink.ts
@@ -0,0 +1,89 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+
+import { TextEncoder } from "internal:deno_web/08_text_encoding.js";
+import {
+  intoCallbackAPIWithIntercept,
+  MaybeEmpty,
+  notImplemented,
+} from "internal:deno_node/polyfills/_utils.ts";
+import { fromFileUrl } from "internal:deno_node/polyfills/path.ts";
+import { promisify } from "internal:deno_node/polyfills/internal/util.mjs";
+
+type ReadlinkCallback = (
+  err: MaybeEmpty<Error>,
+  linkString: MaybeEmpty<string | Uint8Array>,
+) => void;
+
+interface ReadlinkOptions {
+  encoding?: string | null;
+}
+
+function maybeEncode(
+  data: string,
+  encoding: string | null,
+): string | Uint8Array {
+  if (encoding === "buffer") {
+    return new TextEncoder().encode(data);
+  }
+  return data;
+}
+
+function getEncoding(
+  optOrCallback?: ReadlinkOptions | ReadlinkCallback,
+): string | null {
+  if (!optOrCallback || typeof optOrCallback === "function") {
+    return null;
+  } else {
+    if (optOrCallback.encoding) {
+      if (
+        optOrCallback.encoding === "utf8" ||
+        optOrCallback.encoding === "utf-8"
+      ) {
+        return "utf8";
+      } else if (optOrCallback.encoding === "buffer") {
+        return "buffer";
+      } else {
+        notImplemented(`fs.readlink encoding=${optOrCallback.encoding}`);
+      }
+    }
+    return null;
+  }
+}
+
+export function readlink(
+  path: string | URL,
+  optOrCallback: ReadlinkCallback | ReadlinkOptions,
+  callback?: ReadlinkCallback,
+) {
+  path = path instanceof URL ? fromFileUrl(path) : path;
+
+  let cb: ReadlinkCallback | undefined;
+  if (typeof optOrCallback === "function") {
+    cb = optOrCallback;
+  } else {
+    cb = callback;
+  }
+
+  const encoding = getEncoding(optOrCallback);
+
+  intoCallbackAPIWithIntercept<string, Uint8Array | string>(
+    Deno.readLink,
+    (data: string): string | Uint8Array => maybeEncode(data, encoding),
+    cb,
+    path,
+  );
+}
+
+export const readlinkPromise = promisify(readlink) as (
+  path: string | URL,
+  opt?: ReadlinkOptions,
+) => Promise<string | Uint8Array>;
+
+export function readlinkSync(
+  path: string | URL,
+  opt?: ReadlinkOptions,
+): string | Uint8Array {
+  path = path instanceof URL ? fromFileUrl(path) : path;
+
+  return maybeEncode(Deno.readLinkSync(path), getEncoding(opt));
+}