Add a task instancePolicy to task runOptions.

[alexr00]

When a task has reached the max number of instances it can have (default is 1, can be changed with instanceLimit) the instancePolicy determines what happens when another instance is started.

History: #32264
PR for insanceLimit which is relevant to anyone interested in implementing instancePolicy: #89872

[alpalla]

I can keep working on this. Just to reiterate (basing myself off this comment), should instancePolicy provide the following options?

1. terminate the last instance
2. terminate the first instance
3. ask which instance to terminate
4. do nothing and possibly indicate that the instance limit has been reached

I imagine the first 3 options would also have a restart counterpart.

[alexr00]

1. terminate the last instance

Yes, let's call it terminateNewest

2. terminate the first instance

terminateOldest

3. ask which instance to terminate

prompt? I'm not 100% on this name yet. But this should be the default and use the existing behavior with the notification.

4. do nothing and possibly indicate that the instance limit has been reached

I'm not sure which would be more useful here: show no indication that the instance limit has been hit or notify. Maybe we need two options: warn and silent

I don't think we need any restart options since you are effectively restarting by terminating one of the existing instances.

[alpalla]

@alexr00 I'm a little confused about the prompt option.
This option asks the user which of the N active instances to terminate, correct?
How would this option use the existing behavior with the notification?

So far my understanding for how to handle prompt would be to open the QuickPick and show all instances of the task, then when an instance is selected it would be terminated.

[alexr00]

For prompt, yes it would be ideal to show the quick pick instead of the notification.

[fatfatson]

waiting for improve

[darylknowles]

In the most recent release I am now getting prompted to restart or terminate when I try to run scripts from the NPM Task explorer from two different open working folders (and package.json files) that happen to share the same name. For example, running "start" from workspace folder 1 then trying to also run "start" from workspace folder 2 causes the prompt. I suspect we're not using the full paths to detect # of instances already running.