1 files changed, 83 insertions, 0 deletions
diff --git a/ext/node/polyfills/tty.js b/ext/node/polyfills/tty.js
new file mode 100644
index 000000000..54f8f6eae
--- /dev/null
+++ b/ext/node/polyfills/tty.js
@@ -0,0 +1,83 @@
+// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
+
+import { ERR_INVALID_FD } from "ext:deno_node/internal/errors.ts";
+import { LibuvStreamWrap } from "ext:deno_node/internal_binding/stream_wrap.ts";
+import { providerType } from "ext:deno_node/internal_binding/async_wrap.ts";
+import { Duplex } from "node:stream";
+const { Error } = globalThis.__bootstrap.primordials;
+
+// Returns true when the given numeric fd is associated with a TTY and false otherwise.
+function isatty(fd) {
+  if (typeof fd !== "number") {
+    return false;
+  }
+  try {
+    return Deno.isatty(fd);
+  } catch (_) {
+    return false;
+  }
+}
+
+class TTY extends LibuvStreamWrap {
+  constructor(handle) {
+    super(providerType.TTYWRAP, handle);
+  }
+}
+
+export class ReadStream extends Duplex {
+  constructor(fd, options) {
+    if (fd >> 0 !== fd || fd < 0) {
+      throw new ERR_INVALID_FD(fd);
+    }
+
+    // We only support `stdin`.
+    if (fd != 0) throw new Error("Only fd 0 is supported.");
+
+    const tty = new TTY(Deno.stdin);
+    super({
+      readableHighWaterMark: 0,
+      handle: tty,
+      manualStart: true,
+      ...options,
+    });
+
+    this.isRaw = false;
+    this.isTTY = true;
+  }
+
+  setRawMode(flag) {
+    flag = !!flag;
+    this._handle.setRaw(flag);
+
+    this.isRaw = flag;
+    return this;
+  }
+}
+
+export class WriteStream extends Duplex {
+  constructor(fd) {
+    if (fd >> 0 !== fd || fd < 0) {
+      throw new ERR_INVALID_FD(fd);
+    }
+
+    // We only support `stdin`, `stdout` and `stderr`.
+    if (fd > 2) throw new Error("Only fd 0, 1 and 2 are supported.");
+
+    const tty = new TTY(
+      fd === 0 ? Deno.stdin : fd === 1 ? Deno.stdout : Deno.stderr,
+    );
+
+    super({
+      readableHighWaterMark: 0,
+      handle: tty,
+      manualStart: true,
+    });
+
+    const { columns, rows } = Deno.consoleSize();
+    this.columns = columns;
+    this.rows = rows;
+  }
+}
+
+export { isatty };
+export default { isatty, WriteStream, ReadStream };