b4nst/stream-mock

/**
 * @module writable
 */
import {Writable, WritableOptions} from 'stream'

import {WARNINGS} from '../constant'
import {chunk2Buffer} from '../helpers'
import warnOnce from '../helpers/warnOnce'

import IWritableMock from './IWritableMock'

/**
 * WritableMock write its data ton an internal, public accessible buffer.
 * When finished, the data are flatten and accessible through flatData property.
 * @deprecated Please use [[BufferWritableMock]] or [[ObjectWritableMock]] to get a better type accuracy.
 */
export default class WritableMock extends Writable implements IWritableMock {
  public objectMode: boolean;
  /**
   * Internal buffer, filled on every write
   */
  public data: any[];
  /**
   * Data flattern, filled on final callback (when [[WritableMock.end]]) is called.
   */
  public flatData: any[] | Buffer;

  private _writableState;

  /**
   * @param options Writable stream options.
   */
  constructor(options: WritableOptions = {}) {
    warnOnce(WARNINGS.DEP_WRITABLE_MOCK);
    super(options);
    this.data = [];
  }

  // tslint:disable-next-line:function-name Not responsible of this function name
  public _write(
    chunk: any,
    encoding: BufferEncoding,
    callback: (error?: Error | null) => void
  ) {
    this.data.push(
      this._writableState.objectMode ? chunk : chunk2Buffer({ chunk, encoding })
    );
    callback();
  }

  // tslint:disable-next-line:function-name Not responsible of this function name
  public _final(callback: (error?: Error | null) => void) {
    this.flatData = this._writableState.objectMode
      ? [].concat(...this.data)
      : Buffer.concat(this.data);
    callback();
  }
}