Segmentation for monorepos about dd-trace-js

[juan-fernandez]

I've pushed #4128 to grab the displayName config and attach it to a tag that you can use to group by / filter 😄.

If a "test session" is a single invocation of jest, then it might be trickier to do in a hierarchical way 🤔

Can you think of a different way to do it? I'm interested in hearing your feedback

[abejfehr]

Sorry that I didn't get a chance to test yet 😅 thank you so much for the PR, I appreciate your responsiveness

[juan-fernandez]

hey @abejfehr ! Thanks for posting this, it's a great piece of feedback.

In your example, as far as I understand, jest will not run the all the tests in package-a before starting with package-b: this makes it hard to group tests in each package in any meaningful way, as tests for every package will be scattered across the whole test session (=test command).

This said, I think adding the displayName as metadata in the test and test suites is low hanging fruit and it's something we should definitely do.

It would be nice to see how long monorepo -> package-a takes vs monorepo -> package-b

Given how jest runs tests in different packages (as I explain above), can you think of a way we could do this? I might be missing something (or wrong about something) and this is a feature that I think would be valuable.

[abejfehr]

If a "test session" is a single invocation of jest, then it might be trickier to do in a hierarchical way 🤔

In any case, having displayName as a custom field would be kind of nice for grouping runs by packages that ran

Edit: Ironically, we don't currently set displayName it's just something I saw in Jest's config that might make this easier and I'd be happy to add it to our configs

[juan-fernandez]

@abejfehr after the next release you'll be able to use test.jest.display_name tag to grab whatever you have configured in displayName 😄