[task] It shouldn't be possible to assign status from outside

[jrencz]

Which package(s) are affected?

Task (@lit/task)

Description

I noticed that it's possible to set the status of a task manually, from outside, not via args, but just by assigning a value to task.status.

As long as the value is valid TaskStatus (let's say: TaskStatus.ERROR), it will result in rendering using expected renderer, but

• only on a following update (unless this.requestUpdate() is called as well:

   this.task.status = TaskStatus.ERROR
   this.requestUpdate();

• onError of the task won't run
• taskComplete promise won't be rejected

I think this is a bug and that status should be reimplemented as a getter so it's not possible to set state from outside.

It is potentially a breaking change - users might have already started exploiting that behaviour in case there's neither onError nor one uses taskComplete rejections

Reproduction

repro

Demo shows that it's possible to make task render with error renderer 2 ways

• one way that's arguably "correct", one that will make onError run and will make taskComplete promise get rejected,
• one way that's IMO wrong and shouldn't be allowed, one which doesn't make onError or taskComplete promise rejected

Workaround

To prepare a task in such way that there's a way to fail it if it's needed (repro has such way)

Is this a regression?

No or unsure. This never worked, or I haven't tried before.

Affected versions

all

Browser/OS/Node environment

all

[augustjk]

That makes sense to me. It would be weird for a user to set the task status themselves. I can't think of a valid reason for that to happen. So making it a getter instead sounds reasonable.