daruk-cli/src/lib/generate/filter.js

init Daruk repository with template

const match = require('minimatch')
const evaluate = require('./eval')

module.exports = (filters) => {
  return (files, metalsmith, done) => {
    filter(files, filters, metalsmith.metadata(), done)
  }
}

function filter (files, filters, data, done) {
  if (!filters) {
    return done()
  }
  const fileNames = Object.keys(files)
  Object.keys(filters).forEach(glob => {
    fileNames.forEach(file => {
      if (match(file, glob, { dot: true })) {
        const condition = filters[glob]
        if (!evaluate(condition, data)) {
          delete files[file]
        }
      }
    })
  })
  done()
}