Exiting the entire pipeline early if a condition is met [help]

[bakaburg1]

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Description

Hi! Is there a way to conclude a pipeline if a condition is met?
I have a target that compiles a set of combinations of parameters and then filters out the already processed combinations based on a set of files, each with the combination results.
The leftover combinations are then mapped to branches to be processed.

I decided to use the files as ground truth since I needed something easy to inspect; also, the mere existence of the file is not enough to skip the reprocessing since its content is also relevant to this decision.

But if all combinations have already been processed, the pipeline does error: map() cannot be run on an empty set.

I'd like to have a more graceful stopping if this condition is met, but I could not find a graceful way of stopping the pipelines without marking all downstream targets as errored.
The best I could come up with is a conditional stop() and error = "abridge" in the combination target which produces this:

✔ skipping targets (1 so far)...
▶ dispatched target combinations
▶ recorded workspace combinations
✖ errored target combinations
Error: All combinations were already processed.

✖ errored pipeline [2.114 seconds]

It's better than a full-fledged error or a bunch of errored branches, but still, it's reported as an errored pipeline, which is not truthful.

Is there any more elegant solution that marks the pipeline as successfully completed?

[wlandau]

targets isn't designed for this, so there isn't a perfect solution. The error sounds like it gets the job done. Another thing you could try is to have each target check the condition and then run tar_cancel() if it is already met.