[MM-46694] A/B Test: welcome post (#20926)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

store/storetest/mocks/UserStore.go

@@ -569,6 +569,27 @@ func (_m *UserStore) GetEtagForProfilesNotInTeam(teamID string) string {
 	return r0
 }
 
+// GetFirstSystemAdminID provides a mock function with given fields:
+func (_m *UserStore) GetFirstSystemAdminID() (string, error) {
+	ret := _m.Called()
+
+	var r0 string
+	if rf, ok := ret.Get(0).(func() string); ok {
+		r0 = rf()
+	} else {
+		r0 = ret.Get(0).(string)
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func() error); ok {
+		r1 = rf()
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
 // GetForLogin provides a mock function with given fields: loginID, allowSignInWithUsername, allowSignInWithEmail
 func (_m *UserStore) GetForLogin(loginID string, allowSignInWithUsername bool, allowSignInWithEmail bool) (*model.User, error) {
 	ret := _m.Called(loginID, allowSignInWithUsername, allowSignInWithEmail)

store/storetest/user_store.go

@@ -94,6 +94,7 @@ func TestUserStore(t *testing.T, ss store.Store, s SqlStore) {
 	t.Run("ResetLastPictureUpdate", func(t *testing.T) { testUserStoreResetLastPictureUpdate(t, ss) })
 	t.Run("GetKnownUsers", func(t *testing.T) { testGetKnownUsers(t, ss) })
 	t.Run("GetUsersWithInvalidEmails", func(t *testing.T) { testGetUsersWithInvalidEmails(t, ss) })
+	t.Run("GetFirstSystemAdminID", func(t *testing.T) { testUserStoreGetFirstSystemAdminID(t, ss) })
 }
 
 func testUserStoreSave(t *testing.T, ss store.Store) {
@@ -4163,6 +4164,30 @@ func testCount(t *testing.T, ss store.Store) {
 	}
 }
 
+func testUserStoreGetFirstSystemAdminID(t *testing.T, ss store.Store) {
+	sysAdmin := &model.User{}
+	sysAdmin.Email = MakeEmail()
+	sysAdmin.Roles = model.SystemAdminRoleId + " " + model.SystemUserRoleId
+	sysAdmin, err := ss.User().Save(sysAdmin)
+	require.NoError(t, err)
+	defer func() { require.NoError(t, ss.User().PermanentDelete(sysAdmin.Id)) }()
+
+	// We need the second system admin to be created after the first one
+	// our granulirity is ms
+	time.Sleep(1 * time.Millisecond)
+
+	sysAdmin2 := &model.User{}
+	sysAdmin2.Email = MakeEmail()
+	sysAdmin2.Roles = model.SystemAdminRoleId + " " + model.SystemUserRoleId
+	sysAdmin2, err = ss.User().Save(sysAdmin2)
+	require.NoError(t, err)
+	defer func() { require.NoError(t, ss.User().PermanentDelete(sysAdmin2.Id)) }()
+
+	returnedId, err := ss.User().GetFirstSystemAdminID()
+	require.NoError(t, err)
+	require.Equal(t, sysAdmin.Id, returnedId)
+}
+
 func testUserStoreAnalyticsActiveCount(t *testing.T, ss store.Store, s SqlStore) {
 
 	cleanupStatusStore(t, s)