Things that happen are for instance `Thread sleep 1000000 `

Question

Things that happen are for instance `Thread sleep 1000000 ` I wanted to interrupt this Co routine but it s impossible

manueldidonna · Answer

Could you explain me your use case

marstran · Answer

Use `delay` instead `Thread sleep` blocks the thread

marstran · Answer

`delay` suspends the coroutine so it will react on a cancellation

LeoColman · Answer

It s a library I don t know what the user will be using and I need to interrupt it

LeoColman · Answer

It s a testing library that will run arbitrary code but must interrupt it if it s over a certain timeout

LeoColman · Answer

I can t know if user s code will execute `Thread sleep forever ` but I still need to interrupt it

gildor · Answer

You cannot interrupt blocking code The only way is shutdown thread but it will work only if blocking operation handless interruption exception Thread sleep does but it s pretty rare thing for things like while true it just doesn t work Also you cannot reuse thread after shutdown

gildor · Answer

And this is not something coroutines related exatly the same you have in Java and with raw threads Java doesn t have thread stopping starting from version 1 1 or 1 2 just because it wouldn t be possible to write reliable resources or exception management

gildor · Answer

What is your real use case

LeoColman · Answer

This is my real use case

LeoColman · Answer

With < C18FWPKKL|kotlintest> we allow users to test pieces of code and configure a test to have a maximum time to execute

LeoColman · Answer

However if the user s code have a infinite loop by mistake it will never finish and the tests won t end

LeoColman · Answer

For this I wanted to interrupt the code that it s executing

LeoColman · Answer

But I don t think it s very possible with CoRoutines I also don t know if I should be thinking about this JUnit does for example

LeoColman · Answer

In JUnit you can interrupt a while true

gildor · Answer

Coroutines can do nothing with blocked thread same way as pure Java

LeoColman · Answer

What I tried to do was something like this Initialize a CoroutineScope gt Run user code inside it Initializa a CoroutineScope gt Interrupt the first job if it elapses X time

gildor · Answer

I believe you should shutdown vm instance

gildor · Answer

Like Junit

LeoColman · Answer

Interesting

LeoColman · Answer

This leads to another discussion if I should actually care about users code leading to infinite loops

gildor · Answer

You can try interrupt thread but for most real use cases it will not work

gildor · Answer

It will help with Thread sleep but not with infinite loop so for your use case it is almost useless

gildor · Answer

So for such cases the only case is kill vm process

gildor · Answer

One more not so good solution you can just abandon blocked thread and notify user about time out But it may be not really good to have those infinite threads in background that also accumulated on each test suite run

LeoColman · Answer

That may be an alternative I could also just fail the test if I m not able to cancel it But how to do this with coroutines tho The `routine await ` will never complete right

LeoColman · Answer

I mean fail the test and leave the thread hanging

LeoColman · Answer

This specific scenario is Test that this block of code runs in less than Xms

louiscad · Answer

< LeoColman> Maybe you re looking for `System exit someNonZeroIntegerValue ` If your coroutine runs on a non blocked thread it can still be around to call this and shutdown the VM with this call

LeoColman · Answer

I m not I need the JVM to keep running as other tests might run

louiscad · Answer

< LeoColman> Then you can fail the test while letting the faulty code under test run then when all tests are done you shutdown the VM which will stop the faulty code altogether