Does anyone use `unseen`?

[max-sixty]

Unseen — Accept all new (previously unseen) — allows automatically accepting snapshots which don't yet exist. I can't see it being that helpful — generally I either want to review any snapshots, or I'm running with --accept and will review in git.

There's some logic from ages ago that looks wrong,

insta/insta/src/runtime.rs

Lines 520 to 525 in ce2b3fd

	// TODO: this seems to be making `unseen` be true when there is an
	// existing snapshot file; which seems wrong??
	let unseen = self
	.snapshot_file
	.as_ref()
	.map_or(false, |x| fs::metadata(x).is_ok());

, and rather than fix & test it, I might propose deprecating it. To the extent it is indeed wrong, even less likely that people are using the option.

That said, very possibly others find this useful?

[xamgore]

The only way to know for sure, is deprecating the feature and printing this URL into terminals :))

[max-sixty]

Funny you should suggest that: #668 :)

[JeanMertz]

I might have a use-case for this feature (at least, how I'm currently using it, but I might be mistaken):

I am using insta together with httpmock to test a library that interacts with LLM interfaces. I use env RECORD=1 to record interactions with a live API, and then replay once the initial interaction is recorded. Because the response from the LLM API is non-deterministic, and because httpmock does not record the interaction if the test fails, and because insta fails the test if the snapshot does not exist yet, I have to make sure the tests pass for any new/unseen recordings, which is what I use this flag for.

In fact, I came across this issue as I was looking for a way to set this flag on a per-test basis using the with_settings macro (which doesn't seem possible).

Perhaps I'm "using it wrong", but wanted to chime in with my particular use-case for this feature.

[max-sixty]

I have to make sure the tests pass for any new/unseen recordings, which is what I use this flag for.

thanks @JeanMertz

to confirm — unseen will accept previously unseen snapshots. but insta always runs & tests every snapshot; there's no way to only run & test a snapshot if it's new

does unseen help in your case?

(fwiw if I'm accurate I would suggest looking at something like a vcr / cassette implementation if that exists in rust, rather than trying to fix at the snapshot level)