mdx-util/deprecated-packages/mdxc/lib/importsToCommonJS.js

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = transform;
// From https://github.com/tomitrescak/transform-to-commonjs/blob/master/src/index.ts
// Copyright Tomi Trescak

var stringLiteral = '"[^"\\\\]*(?:\\\\.[^"\\\\]*)*"|\'[^\'\\\\]*(?:\\\\.[^\'\\\\]*)*\'';
var pattern = new RegExp('^import\\s+((\\* as )?\\s*([\\w_]+)\\s*)?,?\\s*(\\{\\s*([\\w_,\\s]*)\\s\\})?\\s*(from\\s+)?(' + stringLiteral + ')', 'gm');

function transform(source) {
  pattern.lastIndex = 0;

  // handle imports
  return source.replace(pattern, function (wholeMatch, defaultImport, defaultAs, defaultAsVar, specificImportWrapper, specificImports, fromKeyword, source) {

    if (!fromKeyword) {
      return 'require(' + source + ')';
    } else if (defaultImport && specificImports) {
      return handleDefaultImports(defaultAs, defaultAsVar, defaultImport, source) + '\n' + handleSpecificImports(specificImports, source);
    } else if (defaultImport) {
      return handleDefaultImports(defaultAs, defaultAsVar, defaultImport, source);
    } else if (specificImports) {
      return handleSpecificImports(specificImports, source);
    }
    return wholeMatch;
  });
}

function handleSpecificImports(specificImports, source) {
  specificImports = specificImports.replace(/ as /g, ': ');
  return 'const { ' + specificImports + ' } = require(' + source + ')';
}

function handleDefaultImports(defaultAs, defaultAsVar, defaultImport, source) {
  if (defaultAs) {
    return 'const ' + defaultAsVar.trim() + ' = require(' + source + ')';
  } else {
    return 'const ' + defaultImport.trim() + ' = require(' + source + ').default || require(' + source + ')';
  }
}