Bug: defining transitions top-level in a parallel state tree, transitions other childs back to initial state

[venikx]

XState version

XState version 5

Description

When defining the "on" property at the top-level:

{
  id: "parallelExample",
  type: "parallel",
  on: {
    INQUIRY: {
      target: "#parallelExample.phase.inquiry",
    },
    ARCHIVE: {
      target: "#parallelExample.phase.archive",
    },
    EDIT: {
      target: "#parallelExample.mode.edit",
    },
    NEW: {
      target: "#parallelExample.mode.new",
    },
  },
  states: {
    phase: {
      initial: "inquiry",
      states: {
        inquiry: {
          entry: {
            type: "phase.inq",
          },
        },
        archive: {
          entry: {
            type: "phase.archive",
          },
        },
      },
    },
    mode: {
      initial: "new",
      states: {
        new: {
          entry: {
            type: "mode.new",
          },
        },
        edit: {
          entry: {
            type: "mode.edit",
          },
        },
      },
    },
  },
}

After the non-initial state was set (for example when mode = edit), by default it's "new". When triggering the following

{ type: "ARCHIVED" }

It transitions phase => archived (GOOD), and transitions mode => new (BAD), likely due to mode's initial state being "new".

Expected result

I'd expect only the phase to transition the state, not the mode. When you look at the stately visualizer, it visualizes how I expected it as well: https://stately.ai/registry/editor/a7786eef-4feb-4e0a-8a80-57b27fb7125b?mode=Simulate&machineId=183393aa-804a-4cdc-8c5d-a6fc9a462ee3

• Click on Edit => goes to Edit
• Click on Archived => Edit stays in edit, inquiry becomes archived

Actual result

However, in reality, if you open up the stackblitz, you will notice that transitioning from a

• phase: inquiry
• mode: edit

by pressing ARCHIVE, it will transition to:

• phase: archived
• mode: new

And this is also the bug we encountered in our codebase.

Reproduction

https://stately.ai/registry/editor/a7786eef-4feb-4e0a-8a80-57b27fb7125b?mode=Simulate&machineId=183393aa-804a-4cdc-8c5d-a6fc9a462ee3

Additional context

Notice that the behavior of the stackblitz and stately visualizer is different. So, what I'm suspecting is either a bug in xstate, since the visualizer indicates what I'd expect, while stackblitz doesn't. A misunderstanding on my part, but then stately visualizer output is confusing if the stackblitz version is intended behavior.

Perhaps related to this doc? https://stately.ai/registry/editor/c1ea71b5-dc16-4f52-965d-9eab8f952f83

[Khokhuda]

I think I have similar issue. We have parallel state machine where one parallel state is transitioned from the other parallel state. And everytime such transition happens, state machine seems to just reset itselft and enter every parallel state child state again and their initial states in turn. On Xstate v4 same logic worked correctly and in Xstate v5 I am like really stuck.
The migration manual displays some breaking changes, but parallel states seem to be completely broken.