app.build.rules.html = new Rule(app, {
  test: ({store}) => store.get('patterns.html'),
  use: ({build}) => [build.items.html],
})

app.build.setRule('html', {
test: ({store}) => store.get('patterns.html'),
use: ({build}) => [build.items.html],
})

const myRule = app.build.makeRule({
 test: ({store}) => store.get('patterns.html'),
 use: ({build}) => [build.items.html],
})
 
// later you can assign it
Object.assign(app.build.rules, {myRule})

app.build
  .makeRule()
  .setTest(({store}) => store.get('patterns.font'))
  .setExclude(({store}) => store.get('patterns.modules'))
  .setType('asset')
  .setGenerator({filename: 'assets/[name][ext]'})
  .setParser({
    dataUrlCondition: {
      maxSize: 50000,
    },
  })

app.build.rules.js.getTest(app)

app.build.rules.js.getTest()