Update MigratingFromXCTest making it clear you must import Testing.

[Sajjon]

Update MigratingFromXCTest to make it clear one must import Testing

Motivation:

Other guides mention that one has to import Testing, e.g. DefiningTests, but readers will see MigratingFromXCTest before they see DefiningTests, and "following along" while reading makes code not compile (since must import Testing).

Modifications:

Made it clear that with XCTest one needs import XCTest and now with swift-testing one needs to import Testing.

Result:

A more clear guide, that is easier to follow along.

Checklist:

• Code and documentation should follow the style of the Style Guide.
• If public symbols are renamed or modified, DocC references should be updated.

[grynspan]

Thanks for taking a look at this! We should strive to avoid redundant content in the code snippets that may make it harder to see the difference between the two libraries. The code snippets aren't meant to represent complete Swift files, but simply examples of how various features are used.

Rather than including the import statements in each snippet, how about adding a short section after "Adding the testing library as a dependency" but before "Converting test classes" that explains the change in imported libraries?

I would also take the time to mention in that section that a single test file can contain tests written with either library (i.e. it is okay to continue importing XCTest if not all tests in a file are ready to be converted to swift-testing.) If you can think of other relevant information, feel free to add it too.

[Sajjon]

@grynspan Perhaps like this?

[grynspan]

@swift-ci please test

[SeanROlszewski]

This could be re-phrased so it's more concise:

Using the two frameworks in a single file is supported. To do so, import both XCTest and Testing.

[grynspan]

swift-testing is a package though, not a framework. So that may be confusing.

[SeanROlszewski]

Replace framework with library. Since there are a lot of situations where those terms are used interchangeably in day-to-day work, that casualness slipped into my suggestion. Aside from that one word, I think that sentence is a better explanation.

[Sajjon]

Should I change to:

Using the two libraries in a single file is supported. To do so, import both XCTest and Testing.

?

[grynspan]

I think what we've got here is fine as-is. @SeanROlszewski how strongly do you feel about it?

[SeanROlszewski]

Sounds good to me!

[grynspan]

Great! @Sajjon If you're ready to merge, let me know.

[Sajjon]

@grynspan good to merge IMO.

What do I need to do? Update source branch with head? Rebase or merge main into source?

Looks like there are no conflicts so GitHub ought to be able to merge it as is (I m on GitHub iOS app currently so not as "glanceable")

[grynspan]

I'll merge for you since you can't click the big green button yourself. :)

[briancroom]

Thanks for the contribution, @Sajjon! I like this.

[grynspan]

I am on vacation through the end of the year, so the rest of the team can assist you with landing this PR. Thanks again!