How to intentionally fail a task during the task execution?

[jk-1]

How can I mark a current task as failed?

If I e.g. need to execute os commands inside the task and these commands return zero on success and otherwise non-zero, how can I turn these return values into mill task success or failure?

I can of course throw exception in case of non-zero return value to avoid the creation of meta.json file but are there any other ways to fail the task?

[lefou]

Thrown exceptions are automatically lifted to Result.Exception. Alternatively, you can explicitly return a Result.Failure and give a meaningful error message. The only downside is, that the compiler is no longer automatically converting the success case into a Result, so you need to wrap the successful return value in a Result.Success.

[jk-1]

Thank you! This is just what I was looking for.

[jk-1]

Please add this piece of information (with a small code example) as a part of the mill documentation. I think it is not yet mentioned there.

[lefou]

Good idea