Generated by XState Viz: https://xstate.js.org/viz

machine.js

const bundlerMachine = Machine({
  id: 'bundlermachine',
  type: 'parallel',
  context: {
    queuedUpdateFiles: {},
    weWantToEmit: false,
    fileQueuedForProcessing: null,
  },
  states: {
    worker: {
      initial: 'uninitialized',
      states: {
        uninitialized: {
          on: {
            INITIALIZE: {
              target: 'initializing',
            },
          },
        },
        initializing: {
          invoke: {
            src: 'initilizeBundler',
            id: 'initializeBundler',
            onDone: {
              target: 'idle',
            },
          },
        },
        idle: {
          entry: [send('POP')],
          on: {
            PUSH: {
              actions: [send('POP')],
            },
            PROCESS_FILE_FROM_QUEUE: {
              target: 'processing',
              actions: [
                actions.log((context, event) => {
                  console.log('YEEEHAW', context, event)
                }),
              ],
            },
          },
        },
        processing: {
          invoke: {
            id: 'sendUpdateFileMessage',
            src: 'sendUpdateFileMessage',
            onDone: {
              target: 'idle',
              actions: [
                assign({
                  fileQueuedForProcessing: (context, event) => {
                    return null
                  },
                }),
              ],
            },
          },
        },
      },
    },
    queue: {
      initial: 'empty',
      states: {
        empty: {
          on: {
            PUSH: {
              target: 'pushing',
            },
          },
        },
        ready: {
          on: {
            PUSH: {
              target: 'pushing',
            },
            POP: {
              target: 'popping',
            },
          },
        },
        pushing: {
          entry: [
            assign({
              queuedUpdateFiles: (context, event) => {
                const updatedQueue = {
                  ...context.queuedUpdateFiles,
                  [event.payload.fileName]: event.payload.fileContent,
                }
                return updatedQueue
              },
              weWantToEmit: (context, event) => event.payload.weWantToEmit,
            }),
          ],
          on: {
            '': [
              {
                target: 'empty',
                cond: (context) => Object.keys(context.queuedUpdateFiles).length === 0,
              },
              {
                target: 'ready',
              },
            ],
          },
        },
        popping: {
          entry: [
            assign((context) => {
              const filenames = Object.keys(context.queuedUpdateFiles)
              const queueLength = filenames.length
              const lastOne = queueLength === 1
              // Only emit if this is the last queued file and we actually wanted it to emit
              const emitWithThisFile = context.weWantToEmit && lastOne
              const emitNextBuild = lastOne ? false : context.weWantToEmit
              const filename = filenames[0]
              const content = context.queuedUpdateFiles[filename]
              const updatedQueue = {
                ...context.queuedUpdateFiles,
              }
              delete updatedQueue[filename]
              return {
                ...context,
                queuedUpdateFiles: updatedQueue,
                fileQueuedForProcessing: {
                  fileName: filename,
                  fileContent: content,
                  shouldEmit: emitWithThisFile,
                },
                weWantToEmit: emitNextBuild,
              }
            }),
            send('PROCESS_FILE_FROM_QUEUE'),
          ],
          on: {
            '': [
              {
                target: 'empty',
                cond: (context) => Object.keys(context.queuedUpdateFiles).length === 0,
              },
              {
                target: 'ready',
              },
            ],
          },
        },
      },
    },
  },
})