snippet-cutter/index.js

Returns a subset of a string, composed by complete subsets found using delimeter between min and max length. If no complete subsets are found, returns a subset using length max and ellipsis.

var defaults = require('lodash.defaults')

var defaultOptions = {
  min: 1,
  max: 140,
  ellipsis: '...',
  delimeter: '.'
}

module.exports = function snippetCutter (str, opts) {
  const options = defaults({}, opts, defaultOptions)
  return str.split(options.delimeter).reduce((snippet, sentence) => {
    if (options.min >= options.max) {
      options.max = options.min
    }
    if (snippet.length < options.min) {
      return snippet.concat(sentence + options.delimeter)
    }
    if (snippet.length > (options.max + options.ellipsis.length)) {
      return snippet.slice(0, options.max) + options.ellipsis
    }
    return snippet
  }, '')
}