Something like expect.snapshot

[Chriscbr]

Community Note

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Feature Spec

Starting in Wing v0.x, wing test now saves test snapshots when the matches_snapshot(json) function is used:

bring cloud;

new cloud.Function(inflight () => {
  let data = Json { a: 123, b: "boo" };
  assert(matches_snapshot(data));
}) as "test";

After the first time running the test, an app.w.snap file will be generated containing a sequence of recorded snapshot values associated with each test.

Use Cases

Asserting that outputs generated by user code is as expected.

See https://blog.janestreet.com/the-joy-of-expect-tests/

Implementation Notes

Do snapshots for preflight and inflight require different APIs or mechanisms?

Perhaps we can try implementing this in userland first (using extern)

Component

SDK, Development Environment

[github-actions]

Hi,

This issue hasn't seen activity in 60 days. Therefore, we are marking this issue as stale for now. It will be closed after 7 days.
Feel free to re-open this issue when there's an update or relevant information to be added.
Thanks!

[staycoolcall911]

I believe this was done by @MarkMcCulloh

[Chriscbr]

@staycoolcall911 my apologies - I think the issue might have not been explained well. 😅

I rewrote the description to explain how this would be part of Wing's built-in testing functions - let me know if it makes better sense.

[eladb]

Snapshot format should be a markdown file that shows the output directory in a beautiful and attractive and GitHub readable format.

Credits: @MarkMcCulloh