CallbackWritable.ts

// Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
// See LICENSE in the project root for license information.

import { TerminalWritable } from './TerminalWritable';
import type { ITerminalChunk } from './ITerminalChunk';

/**
 * Constructor options for {@link CallbackWritable}.
 * @public
 */
export interface ICallbackWritableOptions {
  onWriteChunk: (chunk: ITerminalChunk) => void;
}

/**
 * This class enables very basic {@link TerminalWritable.onWriteChunk} operations to be implemented
 * as a callback function, avoiding the need to define a subclass of `TerminalWritable`.
 *
 * @remarks
 * `CallbackWritable` is provided as a convenience for very simple situations. For most cases,
 * it is generally preferable to create a proper subclass.
 *
 * @privateRemarks
 * We intentionally do not expose a callback for {@link TerminalWritable.onClose}; if special
 * close behavior is required, it is better to create a subclass.
 *
 * @public
 */
export class CallbackWritable extends TerminalWritable {
  private readonly _callback: (chunk: ITerminalChunk) => void;

  public constructor(options: ICallbackWritableOptions) {
    super();
    this._callback = options.onWriteChunk;
  }

  protected onWriteChunk(chunk: ITerminalChunk): void {
    this._callback(chunk);
  }
}