TEST(QueryProjectionTest, PositionalProjectionDoesNotPreserveParent) {
    auto proj = createFindProjection("{'a.b': {$elemMatch: {$eq: 0}}}", "{'a.b.$': 1}");
    ASSERT_FALSE(proj.isFieldRetainedExactly("a"));
}
TEST(QueryProjectionTest, PositionalProjectionDoesNotPreserveParent) {
    auto proj = createFindProjection("{'a.b': {$elemMatch: {$eq: 0}}}", "{'a.b.$': 1}");
    ASSERT_FALSE(proj.isFieldRetainedExactly("a"));
}