Context cancellation is not always desirable. I personally have been bitten multiple times by the default behavior of errgroup.

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CamouflagedKiwi 2 days ago | parent [-]

You have to explicitly propagate the group's context if you want it to cancel. You can just not do that if you don't want - there certainly are cases for that.

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Cyph0n a day ago | parent [-]

But if you’re looking at the package API, there is no alternative constructor for Group, which makes it seem as if the most common default is to construct a Group using WithContext. Also, 2/3 of the examples use WithContext.

My recommendation would be to have a NewGroup function or equivalent that returns an empty group to surface it as an alternative to WithContext.

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evanelias a day ago | parent [-]

> My recommendation would be to have a NewGroup function or equivalent that returns an empty group

That goes against common practices in Golang, articulated in the second paragraph of https://go.dev/doc/effective_go#allocation_new among many other places.

Also the errgroup documentation specifically says "A zero Group is valid, has no limit on the number of active goroutines, and does not cancel on error." And, as you noted, one of the examples doesn't use WithContext.

	▲	Cyph0n a day ago \| parent [-]
		That’s one of my Go pet peeves - zero/default structs are sometimes valid and sometimes not, and the only way to know is to dig into the docs. I prefer the API to speak for itself, ideally enforced by the language/compiler.