t.Errorf("failed to find contents, got error: %v", err)
	}
	if len(contents) != 0 {
		t.Errorf("expected %d contents, got %d", 0, len(contents))
	}
}

func TestHasManyAssociationReplaceWithNonValidValue(t *testing.T) {
	user := User{Name: "jinzhu", Languages: []Language{{Name: "EN"}}}

	if err := DB.Create(&user).Error; err != nil {
		t.Fatalf("errors happened when create: %v", err)
	}