function transform( chunk, encoding, clbk ) {
	/* eslint-disable no-invalid-this */
	this._idx += 1;
	debug( 'Received a new chunk. Chunk: %s. Encoding: %s. Index: %d.', chunk.toString(), encoding, this._idx );
	this._inspect.call( null, chunk, this._idx );
	this.push( chunk );
	clbk();

	/* eslint-enable no-invalid-this */
}
Implements the `_transform` method.

@private
@param {(Uint8Array|Buffer|string)} chunk - streamed chunk
@param {string} encoding - Buffer encoding
@param {Callback} clbk - callback to invoke after transforming the streamed chunk