watcher.js

const watch = require('watch');
const { basename, join } = require('path');
const { unlinkSync, existsSync } = require('fs');
const { compileContract } = require('./helper');
const { glob } = require('glob');

function compile_for(file) {
  const fileName = basename(file);
  if(fileName.endsWith('.scrypt')) {
    try {
      clean_description_file(fileName)
      compileContract(fileName);
    } catch (error) {
      console.log(error)
    }
  }
}

function clean_description_file(fileName) {
  if(fileName.endsWith('.scrypt')) {
    try {
      const descFile = join(__dirname, 'deployments/fixture/autoGen', fileName.replace('.scrypt', '_desc.json'));
      if (existsSync(descFile)) {
        unlinkSync(descFile)
      }
    } catch (error) {
      console.log(error)
    }
  }
}

if (process.argv[2] === '--gen-desc') {
  glob('contracts/**/*.scrypt', (err, files) => {
    if(err) return
    files.forEach(f => {
      compile_for(f)
    })
  })
} else {
  watch.watchTree('contracts', { interval: 2 }, function (f, curr, prev) {
    if (typeof f == "object" && prev === null && curr === null) {
      // Finished walking the tree
      Object.keys(f).forEach( (file) => {
        compile_for(file)
      })
    } else if (prev === null) {
      // f is a new file
    } else if (curr.nlink === 0) {
      // f was removed
    } else {
      // f was changed
      compile_for(f)
    }
  })
}