utils.js

/*
  MIT License http://www.opensource.org/licenses/mit-license.php
  Author Tobias Koppers @sokra
*/
import path from 'path';

import loaderUtils from 'loader-utils';

const placholderRegExps = {
  importItemG: /___CSS_LOADER_IMPORT___([0-9]+)___/g,
  importItem: /___CSS_LOADER_IMPORT___([0-9]+)___/,
};

function getImportPrefix(loaderContext, importLoaders) {
  if (importLoaders === false) {
    return '';
  }

  const numberImportedLoaders = parseInt(importLoaders, 10) || 0;
  const loadersRequest = loaderContext.loaders
    .slice(
      loaderContext.loaderIndex,
      loaderContext.loaderIndex + 1 + numberImportedLoaders
    )
    .map((x) => x.request)
    .join('!');

  return `-!${loadersRequest}!`;
}

function dashesCamelCase(str) {
  return str.replace(/-+(\w)/g, (match, firstLetter) =>
    firstLetter.toUpperCase()
  );
}

function getLocalIdent(loaderContext, localIdentName, localName, options) {
  if (!options.context) {
    // eslint-disable-next-line no-param-reassign
    options.context = loaderContext.rootContext;
  }

  const request = path
    .relative(options.context, loaderContext.resourcePath)
    .replace(/\\/g, '/');

  // eslint-disable-next-line no-param-reassign
  options.content = `${options.hashPrefix + request}+${localName}`;

  // eslint-disable-next-line no-param-reassign
  localIdentName = localIdentName.replace(/\[local\]/gi, localName);

  const hash = loaderUtils.interpolateName(
    loaderContext,
    localIdentName,
    options
  );

  return hash
    .replace(new RegExp('[^a-zA-Z0-9\\-_\u00A0-\uFFFF]', 'g'), '-')
    .replace(/^((-?[0-9])|--)/, '_$1');
}

function getFilter(filter, resourcePath, defaultFilter = null) {
  return (content) => {
    if (defaultFilter && !defaultFilter(content)) {
      return false;
    }

    if (typeof filter === 'function') {
      return !filter(content, resourcePath);
    }

    return true;
  };
}

export {
  getImportPrefix,
  getLocalIdent,
  placholderRegExps,
  dashesCamelCase,
  getFilter,
};