Generated by XState Viz: https://xstate.js.org/viz/?gist=760d85cb7ed38017a31f958fef883c7e

machine.js

  // Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions
  // - XState (all XState exports)
  
  const fieldMachine = Machine({
    id: 'fetch',
    initial: 'unchanged',
    context: {
      original: 'one',
      current: 'one'
    },
    on: {
      CHANGE: [
        {
          cond: 'isChanged',
          actions: 'storeCurrent',
          target: 'validating'
        },
        {
          actions: 'storeCurrent',
          target: 'unchanged'
        }
      ]
    },
    states: {
      unchanged: {},
      validating: {
        on: {
          VALID: 'submittable',
          INVALID: 'invalid'
        }
      },
      invalid: {},
      submittable: {
        on: {
          SUBMIT: {
            actions: 'save',
            target: 'unchanged'
          }
        }
      },
    }
  },{
    actions:{
      storeCurrent: assign({current: (_, event) => event.value || ''
      }),
      save: assign({original: (c) => c.current})
    },
    guards:{
      isChanged: (c, e) => {
        // console.log('isChanged', c, e)
        return e.value !== c.original
      }
    }
  });
  

Related to statelyai/xstate#1565