Long running task progress/real time output

[fabriciojs]

this is a nice feature to start with, but we need to advise it only works for no-output tasks. If the closure() has some kind of output, this would get messy.

I would like to try exploring something like:

• We have a pipe for capturing the task actual output.
• While executing a task, we have something like:

Running "task"...
-------------------------------
(original task output... keeps writing here)
-------------------------------
... (animated char, something like an ASCII spinner with `-\|/-` replacing sequence, or something for that matter.

So the last output line is ALWAYS our "progress/running" spinner, while above it we keep displaying any eventual output the task could have.

Not sure how to architecture that, we may discuss further, maybe for a future iteration?

Originally posted by @fabriciojs in #170 (comment)

[fabriciojs]

Suggestion: https://github.com/briandowns/spinner

[fabriciojs]

@danielsuguimoto couple comments for us to do a final round on the work on this:

• At line cmd/kool_task.go:95 we may want to get that error to handle somewhere whether it is indeed EOF or something else we should better handle/report.

• Yet at cmd/kool_task.go:95 we need to make sure CPU is not gonna be exhausted, that is, bufReader.ReadString will "wait" for us in non-resource-hungry way.

• Now at cmd/kool_task.go:118, I am not sure the > prefix is best, but I want to see how it looks in practice.

• At cmd/kool_task.go:60 we are ignoring/never printing err itself - is that intentional?

[fabriciojs]

Branch output-control has some WIP related to this.

[fabriciojs]

This has been working great for self-update.