Fix the tests for migration target

Ensure that we test the slice rather than the integer. This is ensures
we can view it as a sliding window.

api/package_test.go

@@ -28,6 +28,7 @@ func (*ImportSuite) TestImports(c *gc.C) {
 		"api/base",
 		"api/watcher",
 		"core/arch",
+		"core/backups",
 		"core/base",
 		"core/constraints",
 		"core/database",

apiserver/facades/controller/migrationtarget/migrationtarget_test.go

@@ -81,8 +81,9 @@ func (s *Suite) TestFacadeRegistered(c *gc.C) {
 	c.Assert(err, jc.ErrorIsNil)
 
 	api, err := aFactory(&facadetest.Context{
-		State_: s.State,
-		Auth_:  s.authorizer,
+		State_:          s.State,
+		Auth_:           s.authorizer,
+		ServiceFactory_: servicefactorytesting.NewTestingServiceFactory(),
 	})
 	c.Assert(err, jc.ErrorIsNil)
 	c.Assert(api, gc.FitsTypeOf, new(migrationtarget.API))

apiserver/facades/controller/migrationtarget/register.go

@@ -110,5 +110,6 @@ func newFacade(ctx facade.Context, facadeVersions facades.FacadeVersions) (*API,
 		credentialcommon.CredentialInvalidatorGetter(ctx),
 		stateenvirons.GetNewEnvironFunc(environs.New),
 		stateenvirons.GetNewCAASBrokerFunc(caas.New),
-		facadeVersions)
+		facadeVersions,
+	)
 }

apiserver/facadeversions_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/juju/juju/api"
 	"github.com/juju/juju/apiserver"
+	"github.com/juju/juju/core/facades"
 	coretesting "github.com/juju/juju/testing"
 )
 
@@ -52,24 +53,24 @@ func (s *facadeVersionSuite) TestFacadeVersionsMatchServerVersions(c *gc.C) {
 	c.Check(apiFacadeVersions, jc.DeepEquals, serverFacadeBestVersions)
 }
 
-// TestClient3xSupport checks that the client facade supports the 3.x for
-// certain tasks. You must be very careful when removing support for facades
+// TestClientSupport checks that the client facade supports the 3.x and 4.x
+// for certain tasks. You must be very careful when removing support for facades
 // as it can break model migrations, upgrades, and state reports.
-func (s *facadeVersionSuite) TestClient3xSupport(c *gc.C) {
+func (s *facadeVersionSuite) TestClientSupport(c *gc.C) {
 	tests := []struct {
 		facadeName       string
 		summary          string
-		apiClientVersion int
+		apiClientVersion facades.FacadeVersion
 	}{
 		{
 			facadeName:       "Client",
 			summary:          "Ensure that the Client facade supports 3.x for status requests",
-			apiClientVersion: 6,
+			apiClientVersion: []int{6},
 		},
 		{
 			facadeName:       "ModelManager",
 			summary:          "Ensure that the ModelManager facade supports 3.x for model migration and status requests",
-			apiClientVersion: 9,
+			apiClientVersion: []int{9},
 		},
 	}
 	for _, test := range tests {
@@ -88,18 +89,17 @@ var Contains gc.Checker = &containsChecker{
 }
 
 func (checker *containsChecker) Check(params []interface{}, names []string) (result bool, err string) {
-	expected, ok := params[1].(int)
+	expected, ok := params[1].(facades.FacadeVersion)
 	if !ok {
-		return false, "expected must be a string"
+		return false, "expected must be a int"
 	}
 
-	obtained, ok := params[0].([]int)
+	obtained, ok := params[0].(facades.FacadeVersion)
 	if ok {
-		for _, v := range obtained {
-			if v == expected {
-				return true, ""
-			}
+		if set.NewInts(expected...).Intersection(set.NewInts(obtained...)).Size() > 0 {
+			return true, ""
 		}
+
 		return false, ""
 	}