[swift-evolution] [Review] SE-0019 Swift Testing (Package Manager)

[Max Howell]

> On Jan 5, 2016, at 12:21 PM, Paul Cantrell <cantrell at pobox.com> wrote:
> 
> Thanks for the clarifications. This helps me understand much better how the proposal plays out.
> 
>> On Jan 5, 2016, at 2:14 PM, Max Howell <max.howell at apple.com> wrote:
>> 
>>> 1. The proposal talks in several places about “test modules” (for example, “test-module is created per subdirectory of Tests”). How do these test modules interact with Package.swift? Does each of them have a separate target? If so, how is the test module name specified in the Target(…) entry?
>> 
>> There is no support for referring to test targets in the Package.swift as part of this proposal.
>> 
>>> 2. Perhaps answered by #1, how does Package.swift specify test-only dependencies (e.g. Quick) that are necessary to build tests, but should not be exported to downstream projects?
>> 
>> This is already a part of the package manager: https://github.com/apple/swift-package-manager/pull/74
> 
> Cool. Hadn’t seen the private dependencies yet.
> 
> Taking 1 and 2 together, does that mean that all dependencies necessary for _all_ the test modules must be downloaded & compiled in order to run _any_ or them? Not ideal, but not a deal-killer either

Yes, and indeed, this isn’t really acceptable, but I think any changes to how this work would involve a discussion on the swift-build-dev mailing list. Really how targets depend on each other and external dependencies in the Package.swift manifest needs some work in general.

>>> 3. You propose that “building a module also builds that module's corresponding tests.” Does this apply only to the top-level package, or to all of its dependencies? For example, if my FooApp depends on BarLib, and BarLib’s tests depend on HugeFancyTestFramework, do I have to download and compile HugeFancyTestFramework in order to build FooApp? (Hopefully not!)
>> 
>> HugeFancyTestFramework will not be downloaded or built.
> 
> That’s a relief!

Probably people would want an option to do this though. You should be running and checking the tests of your dependencies somewhat regularly.

But when developing your own software, this would be a waste of engineering time.