Regarding lifecycle of expect_snapshot_warning()

[njtierney]

I note in

https://testthat.r-lib.org/reference/expect_snapshot_output.html

That expect_snapshot_warning() and co are in a questioning lifecycle.

I personally find it really useful to use expect_snapshot_warning() as a way to capture the entire warning message, and not the output. Is there a recommended way that you'd recommend testing this otherwise? Currently it seems my approach is:

expect_snapshot(
  tmp <- function_to_warn(x)
)

I understand I can capture an error message with:

expect_snapshot(
  error = TRUE,
  function_to_warn(x)
)

But I want to capture the warning. Is there a recommended approach for the future that you'd recommend users use to capture things like warnings?

[hadley]

Yeah, we just do expect_snapshot(. <- function_to_warn(x)) using . to indicate it's not used further.

I'm not convinced that this is better than expect_snapshot_warning() but I'm not also convinced that expect_snapshot_warning() should exist to fulfil this one small need. So no short term plan to change things.

[njtierney]

I do find that one small need very useful, however!

When doing

expect_snapshot(. <- function_to_warn(x))`

This now also captures any other messages that appear - not just the warnings, which is what expect_snapshot_warning() does.

The expectations, expect_error/warning/message() seem like corresponding equivalents to the snapshot counterparts, and so I do find this small need useful.

I can appreciate that you want to draw a line somewhere and not maintain too many functions, but I guess this is my vote to say "I find this useful". And I very much understand that doesn't mean it should be kept. But just wanted to add my voice.

If this function will eventually be deprecated, can I make a PR, or another issue to indicate the best practices going forward?

[hadley]

As I said, there's no plans to change the current status because I'm not convinced it's not needed.

[njtierney]

OK thanks for clarifying! Rereading your message now I see that is what you said! Thanks again :)