def test_read_instances_empty_fields(self): @dataclass(frozen=True) class Dc: pass t = TypedDfBuilder("T").reserve("animal", dtype=str).build() df = t.from_dataclass_instances([Dc()]) assert len(df) == 1 assert "animal" not in df.columns
def test_read_instances(self): @dataclass(frozen=True) class Dc: animal: str val: Optional[int] t = TypedDfBuilder("T").require("animal", dtype=str).reserve("age", dtype=int).build() df = t.from_dataclass_instances([Dc("cat", 1), Dc("kitten", 2)]) assert len(df) == 2 assert df.to_numpy().tolist() == [["cat", 1], ["kitten", 2]]
def test_read_instances_empty(self): t = TypedDfBuilder("T").require("animal", dtype=str).build() df = t.from_dataclass_instances([]) assert len(df) == 0