Get Coverage stats when tests are in another package

Question

My tests aren't in the same package as my code. I find this a less cluttered way of organising a codebase with a lot of test files, and I've read that it's a good idea in order to limit tests to interacting via the package's public api.

So it looks something like this:

api_client:
    Client.go
    ArtistService.go
    ...
api_client_tests
    ArtistService.Events_test.go
    ArtistService.Info_test.go
    UtilityFunction.go
    ...

I can type go test bandsintown-api/api_client_tests -cover and see 0.181s coverage: 100.0% of statements. But that's actually just coverage over my UtilityFunction.go (as I say when I ran go test bandsintown-api/api_client_tests -cover=cover.out and go tool cover -html=cover.out).

Is there any way to get the coverage for the actual api_client package under test, without bringing it all into the same package?

Answer 1

As it is mentioned in comments you can run

go test -cover -coverpkg "api_client" "api_client_tests"

to run the tests with coverage.

But splitting code files from tests files to a different directories isn't a Go's way.

I suppose that you want to have a black-box testing(nothing package-private stuff can be accessible outside, even for tests).

To accomplish this it's allowed to have tests in another package(without moving the files). Example:

api_client.go

package api_client

// will not be accessible outside of the package
var privateVar = 10

func Method() {
}

api_client_test.go

package api_client_tests

import "testing"

func TestClient(t *testing.T) {
    Method()
}