index.js

import React from 'react';
import PropTypes from 'prop-types';
import blacklist from 'blacklist';
import {Text} from 'ink';

const BLACKLIST_PROPS = ['percent', 'left', 'right', 'columns', 'character', 'rightPad'];

class Bar extends React.Component {
  getString() {
    const {percent, columns, left, right, character, rightPad} = this.props;

    const screen = columns || process.stdout.columns || 80;
    const space = screen - right - left;
    const max = Math.min(Math.floor(space * percent), space);
    const chars = character.repeat(max);

    if (!rightPad) {
      return chars;
    }

    return chars + ' '.repeat(space - max);
  }

  render() {
    const props = blacklist(this.props, BLACKLIST_PROPS);
    return (
      <Text {...props}>
        {this.getString()}
      </Text>
    );
  }
}

Bar.defaultProps = {
  columns: 0,
  percent: 1,
  left: 0,
  right: 0,
  character: '█',
  rightPad: false
};

Bar.propTypes = {
  columns: PropTypes.number,
  percent: PropTypes.number,
  left: PropTypes.number,
  right: PropTypes.number,
  character: PropTypes.string,
  rightPad: PropTypes.bool
};

export default Bar;