eleventy filter config

.eleventy.js

const _get          = require("lodash.get");

//It seems like, when using these filters on items in a collection with attributes in frontmatter—the keys are mostly on the data object, e.g. `| where('data.key', 'value')`. When using on global data, look for item attributes directly `| where('key', 'value')`

//sort by order attribute
function sortByOrder(values) {
  let vals = [...values];     // this *seems* to prevent collection mutation...
  return vals.sort((a, b) => Math.sign(a.data.order - b.data.order));
}
//sort collections by title attribute
function sortByTitle(values) {
  return values.slice().sort((a, b) => a.data.title.localeCompare(b.data.title))
}

module.exports = function(eleventyConfig) {

  //Filter helpers
  eleventyConfig.addFilter("sortByOrder", sortByOrder);
  eleventyConfig.addFilter('sortByTitle', sortByTitle);
  
  //Re-creating Jekyll where filter
  eleventyConfig.addFilter("where", (arr, key, compare) => {
    compare = [].concat(compare) // force to arr
    let filtered = arr.filter(item => {
      return compare.includes(_get(item, key));
    })
    return filtered
  })
  
  eleventyConfig.addFilter("removeWhere", (arr, key, compare) => {
    compare = [].concat(compare) // force to arr
    let filtered = arr.filter(item => {
      return !compare.includes(_get(item, key));
    })
    return filtered
  })
  
};