react-dev-utils/typescriptFormatter.js

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

'use strict';

const os = require('os');
const codeFrame = require('@babel/code-frame').codeFrameColumns;
const chalk = require('chalk');
const fs = require('fs');

const issueOrigins = {
  typescript: 'TypeScript',
  internal: 'fork-ts-checker-webpack-plugin',
};

function formatter(issue) {
  const { origin, severity, file, line, message, code, character } = issue;

  const colors = new chalk.constructor();
  const messageColor = severity === 'warning' ? colors.yellow : colors.red;
  const fileAndNumberColor = colors.bold.cyan;

  const source = file && fs.existsSync(file) && fs.readFileSync(file, 'utf-8');
  const frame = source
    ? codeFrame(source, { start: { line: line, column: character } })
        .split('\n')
        .map(str => '  ' + str)
        .join(os.EOL)
    : '';

  return [
    messageColor.bold(`${issueOrigins[origin]} ${severity.toLowerCase()} in `) +
      fileAndNumberColor(`${file}(${line},${character})`) +
      messageColor(':'),
    message + '  ' + messageColor.underline(`TS${code}`),
    '',
    frame,
  ].join(os.EOL);
}

module.exports = formatter;