test_dtype.py

import unittest
import numpy as np
import torch
import operator
from tinygrad.helpers import CI, getenv, DEBUG, OSX, temp
from tinygrad.dtype import DType, DTYPES_DICT, ImageDType, PtrDType, least_upper_float, least_upper_dtype
from tinygrad import Device
from tinygrad.tensor import Tensor, dtypes
from typing import Any, List
from hypothesis import given, settings, strategies as strat

settings.register_profile("my_profile", max_examples=200, deadline=None)
settings.load_profile("my_profile")

core_dtypes = list(DTYPES_DICT.values())
floats = [dt for dt in core_dtypes if dtypes.is_float(dt)]
def is_dtype_supported(dtype: DType, device: str = Device.DEFAULT):
  if dtype == dtypes.bfloat16: return False # numpy doesn't support bf16, tested separately in TestBFloat16DType
  if device in ["WEBGPU", "WEBGL"]: return dtype in [dtypes.float, dtypes.int32, dtypes.uint32]
  # for CI GPU, cl_khr_fp16 isn't supported
  # for CI LLVM, it segfaults because it can't link to the casting function
  # CUDA in CI uses CUDACPU that does not support half
  # PYTHON supports half memoryview in 3.12+ https://github.com/python/cpython/issues/90751
  if dtype == dtypes.half: return not (CI and device in ["GPU", "LLVM", "CUDA"]) and device != "PYTHON"
  if dtype == dtypes.float64: return device != "METAL" and not (OSX and device == "GPU")
  return True

def get_available_cast_dtypes(dtype: DType) -> List[DType]:
  if not is_dtype_supported(dtype): return []
  return [v for k, v in DTYPES_DICT.items() if v != dtype and is_dtype_supported(v) and not k.startswith("_")] # dont cast internal dtypes

def _test_to_np(a:Tensor, np_dtype, target):
  if DEBUG >= 2: print(a)
  na = a.numpy()
  if DEBUG >= 2: print(na, na.dtype, a.lazydata.base.realized)
  try:
    assert na.dtype == np_dtype
    np.testing.assert_allclose(na, target)
  except AssertionError as e:
    raise AssertionError(f"\ntensor {a.numpy()} does not match target {target} with np_dtype {np_dtype}") from e

def _assert_eq(tensor:Tensor, target_dtype:DType, target):
  if DEBUG >= 2: print(tensor.numpy())
  try:
    assert tensor.dtype == target_dtype
    np.testing.assert_allclose(tensor.numpy(), target, rtol=1e-3 if target_dtype == dtypes.float16 else 1e-7)
  except AssertionError as e:
    raise AssertionError(f"\ntensor {tensor.numpy()} dtype {tensor.dtype} does not match target {target} with dtype {target_dtype}") from e

def _test_op(fxn, target_dtype:DType, target):
  _assert_eq(fxn(), target_dtype, target)
def _test_cast(a:Tensor, target_dtype:DType):
  _test_op(lambda: a.cast(target_dtype), target_dtype, list(a.numpy().astype(target_dtype.np)))
def _test_bitcast(a:Tensor, target_dtype:DType, target=None):
  _test_op(lambda: a.bitcast(target_dtype), target_dtype, target or a.numpy().view(target_dtype.np).tolist())

class TestDType(unittest.TestCase):
  DTYPE: Any = None
  DATA: Any = None
  @classmethod
  def setUpClass(cls):
    if not cls.DTYPE or not is_dtype_supported(cls.DTYPE): raise unittest.SkipTest("dtype not supported")
    if dtypes.is_int(cls.DTYPE): cls.DATA = np.random.randint(0, 100, size=10, dtype=cls.DTYPE.np).tolist()
    elif cls.DTYPE == dtypes.bool: cls.DATA = np.random.choice([True, False], size=10).tolist()
    else: cls.DATA = np.random.uniform(0, 1, size=10).tolist()
  def setUp(self):
    if self.DTYPE is None: raise unittest.SkipTest("base class")

  def test_to_np(self): _test_to_np(Tensor(self.DATA, dtype=self.DTYPE), self.DTYPE.np, np.array(self.DATA, dtype=self.DTYPE.np))

  def test_casts_to(self): list(map(
    lambda dtype: _test_cast(Tensor(self.DATA, dtype=dtype), self.DTYPE),
    get_available_cast_dtypes(self.DTYPE)
  ))
  def test_casts_from(self): list(map(
    lambda dtype: _test_cast(Tensor(self.DATA, dtype=self.DTYPE), dtype),
    get_available_cast_dtypes(self.DTYPE)
  ))

  def test_same_size_ops(self):
    list(map(
      lambda dtype: _test_ops(a_dtype=self.DTYPE, b_dtype=dtype) if dtype.itemsize == self.DTYPE.itemsize else None,
      get_available_cast_dtypes(self.DTYPE)
    ))
  def test_upcast_ops(self):
    list(map(
      lambda dtype: _test_ops(a_dtype=self.DTYPE, b_dtype=dtype) if dtype.itemsize > self.DTYPE.itemsize else None,
      get_available_cast_dtypes(self.DTYPE)
  ))
  def test_upcast_to_ops(self):
    list(map(
      lambda dtype: _test_ops(a_dtype=dtype, b_dtype=self.DTYPE) if dtype.itemsize < self.DTYPE.itemsize else None,
      get_available_cast_dtypes(self.DTYPE)
  ))
  def test_bitcast(self):
    if Device.DEFAULT == "WEBGL": raise unittest.SkipTest("no bitcast in WebGL GLSL")
    if self.DTYPE == dtypes.bool: raise unittest.SkipTest("no bools in bitcast")
    list(map(
      lambda dtype:
        _test_bitcast(Tensor(self.DATA, dtype=self.DTYPE), dtype) if dtype.itemsize == self.DTYPE.itemsize and dtype != dtypes.bool else None,
     get_available_cast_dtypes(self.DTYPE)
    ))

  def test_dtypes_fields(self):
    fields = dtypes.fields()
    self.assertTrue(all(isinstance(value, DType) for value in fields.values()))
    self.assertTrue(all(issubclass(value.np, np.generic) for value in fields.values() if value.np is not None))

  def test_resulting_and_init_dtypes_match(self):
    dtypes = list(map(np.dtype, ["bool", "uint8", "int8", "int16", "int32", "int64", "float32", "float64"]))
    data = [1., 2., 0., 0.5, -1.5, 5.25]
    for dt in dtypes:
      arr = np.asarray(data, dtype=dt)
      tin = Tensor(arr).numpy()
      tor = torch.as_tensor(arr).detach().numpy()
      assert dt is tin.dtype is tor.dtype, f"dtype mismatch: expected={dt} | tinygrad={tin.dtype} | torch={tor.dtype}"
      np.testing.assert_allclose(tin, tor, atol=1e-6, rtol=1e-3)

def _test_ops(a_dtype:DType, b_dtype:DType, target_dtype=None):
  target_dtype = target_dtype or least_upper_dtype(a_dtype, b_dtype)
  if not is_dtype_supported(a_dtype) or not is_dtype_supported(b_dtype) or not is_dtype_supported(target_dtype): return
  if a_dtype == dtypes.bool or b_dtype == dtypes.bool: return
  _assert_eq(Tensor([1,2,3,4], dtype=a_dtype)+Tensor([1,2,3,4], dtype=b_dtype), target_dtype, [2,4,6,8])
  _assert_eq((Tensor([1], dtype=a_dtype).cast(b_dtype)+Tensor([1], dtype=a_dtype).cast(b_dtype)).cast(a_dtype), a_dtype, [2])
  _assert_eq(Tensor([1,2,3,4], dtype=a_dtype)*Tensor([1,2,3,4], dtype=b_dtype), target_dtype, [1,4,9,16])
  _assert_eq(Tensor([[1,2],[3,4]], dtype=a_dtype)@Tensor.eye(2, dtype=b_dtype), target_dtype, [[1,2],[3,4]])
  _assert_eq(Tensor([1,1,1,1], dtype=a_dtype)+Tensor.ones((4,4), dtype=b_dtype), target_dtype, 2*Tensor.ones(4,4).numpy())

@unittest.skipUnless(Device.DEFAULT == "LLVM", "bfloat16 not supported")
class TestBFloat16DType(unittest.TestCase):
  def test_bf16_to_float(self):
    with self.assertRaises(AssertionError):
      _test_cast(Tensor([100000], dtype=dtypes.bfloat16), dtypes.float32)

  def test_float_to_bf16(self):
    with self.assertRaises(AssertionError):
      _test_cast(Tensor([100000], dtype=dtypes.float32), dtypes.bfloat16)

  # torch.tensor([10000, -1, -1000, -10000, 20]).type(torch.bfloat16)

  def test_bf16(self):
    t = Tensor([10000, -1, -1000, -10000, 20]).cast(dtypes.bfloat16)
    t.realize()
    back = t.cast(dtypes.float32)
    assert tuple(back.numpy().tolist()) == (9984., -1, -1000, -9984, 20)

  def test_bf16_disk_write_read(self):
    t = Tensor([10000, -1, -1000, -10000, 20]).cast(dtypes.float32)
    t.to(f"disk:{temp('f32')}").realize()

    # hack to "cast" f32 -> bf16
    with open(temp('f32'), "rb") as f: dat = f.read()
    adat = b''.join([dat[i+2:i+4] for i in range(0, len(dat), 4)])
    with open(temp('bf16'), "wb") as f: f.write(adat)

    t = Tensor.empty(5, dtype=dtypes.bfloat16, device=f"disk:{temp('bf16')}").llvm().realize()
    back = t.cast(dtypes.float32)
    assert tuple(back.numpy().tolist()) == (9984., -1, -1000, -9984, 20)

class TestHalfDtype(TestDType): DTYPE = dtypes.half

class TestFloatDType(TestDType):
  DTYPE = dtypes.float

  def test_float_to_uint(self):
    _test_op(lambda: Tensor([-0.9, -0.3, 1.2], dtype=dtypes.float32).cast(dtypes.uint32), dtypes.uint32,
             [0, 0, 1])

class TestDoubleDtype(TestDType):
  DTYPE = dtypes.double
  @unittest.skipIf(getenv("CUDACPU",0)==1, "conversion not supported on CUDACPU")
  @unittest.skipIf(getenv("HIP",0)==1, "HIP renderer does not support f64 precision")
  def test_float64_increased_precision(self):
    for func in [
      lambda t: t.exp(),
      lambda t: t.exp2(),
      lambda t: t.log(),
      lambda t: t.log2(),
      lambda t: t.sqrt(),
      lambda t: t.rsqrt(),
      lambda t: t.sin(),
      lambda t: t.cos(),
      lambda t: t.tan(),
      lambda t: t.sigmoid(),
    ]:
      a = [2, 3, 4]
      np.testing.assert_allclose(func(Tensor(a, dtype=self.DTYPE)).numpy(), func(torch.tensor(a, dtype=torch.float64)), rtol=1e-12, atol=1e-12)

  def test_float64_to_float32_cast_inf(self):
    _test_op(lambda: Tensor([3.4e40, 3.4e38, 1, 0], dtype=dtypes.float64).cast(dtypes.float32),
             dtypes.float32, [float('inf'), 3.4e38, 1, 0])


class TestInt8Dtype(TestDType):
  DTYPE = dtypes.int8
  @unittest.skipIf(getenv("CUDA",0)==1 or getenv("PTX", 0)==1, "cuda saturation works differently")
  def test_int8_to_uint8_negative(self):
    _test_op(lambda: Tensor([-1, -2, -3, -4], dtype=dtypes.int8).cast(dtypes.uint8), dtypes.uint8, [255, 254, 253, 252])

  def test_int8_to_uint16_negative(self):
    _test_op(lambda: Tensor([-1, -2, -3, -4], dtype=dtypes.int8).cast(dtypes.uint16), dtypes.uint16, [2**16-1, 2**16-2, 2**16-3, 2**16-4])

class TestUint8Dtype(TestDType):
  DTYPE = dtypes.uint8
  @unittest.skipIf(getenv("CUDA",0)==1 or getenv("PTX", 0)==1, "cuda saturation works differently")
  def test_uint8_to_int8_overflow(self):
    _test_op(lambda: Tensor([255, 254, 253, 252], dtype=dtypes.uint8).cast(dtypes.int8), dtypes.int8, [-1, -2, -3, -4])

@unittest.skipIf(Device.DEFAULT == "WEBGL", "No bitcast on WebGL")
class TestBitCast(unittest.TestCase):
  def test_shape_change_bitcast(self):
    with self.assertRaises(AssertionError):
      _test_bitcast(Tensor([100000], dtype=dtypes.float32), dtypes.uint8, [100000])

  def test_bitcast_float_to_int32(self):
    a = Tensor([1.,2,3])
    b = a.bitcast(dtypes.int32)
    assert b.numpy()[0] == 0x3f800000

  def test_bitcast_upcasted(self):
    a = Tensor.zeros(100, 4, dtype=dtypes.int32).contiguous() + 0x3f800000
    b = a.bitcast(dtypes.float32)
    assert b.numpy()[0,0] == 1.

class TestInt16Dtype(TestDType): DTYPE = dtypes.int16

class TestUint16Dtype(TestDType):
  DTYPE = dtypes.uint16

  def test_uint16_to_int8_overflow(self):
    _test_op(lambda: Tensor([2**16-1, 2**16-2, 1, 0], dtype=dtypes.uint16).cast(dtypes.int8), dtypes.int8, [-1, -2, 1, 0])

class TestInt32Dtype(TestDType): DTYPE = dtypes.int32
class TestUint32Dtype(TestDType): DTYPE = dtypes.uint32

class TestInt64Dtype(TestDType): DTYPE = dtypes.int64
class TestUint64Dtype(TestDType): DTYPE = dtypes.uint64

class TestBoolDtype(TestDType): DTYPE = dtypes.bool

class TestImageDType(unittest.TestCase):
  def test_image_scalar(self):
    assert dtypes.imagef((10,10)).scalar() == dtypes.float32
    assert dtypes.imageh((10,10)).scalar() == dtypes.float32
  def test_image_vec(self):
    assert dtypes.imagef((10,10)).vec(4) == dtypes.float32.vec(4)
    assert dtypes.imageh((10,10)).vec(4) == dtypes.float32.vec(4)

class TestEqStrDType(unittest.TestCase):
  def test_image_ne(self):
    if ImageDType is None: raise unittest.SkipTest("no ImageDType support")
    assert dtypes.float == dtypes.float32, "float doesn't match?"
    assert dtypes.imagef((1,2,4)) != dtypes.imageh((1,2,4)), "different image dtype doesn't match"
    assert dtypes.imageh((1,2,4)) != dtypes.imageh((1,4,2)), "different shape doesn't match"
    assert dtypes.imageh((1,2,4)) == dtypes.imageh((1,2,4)), "same shape matches"
    assert isinstance(dtypes.imageh((1,2,4)), ImageDType)
  def test_ptr_ne(self):
    if PtrDType is None: raise unittest.SkipTest("no PtrDType support")
    # TODO: is this the wrong behavior?
    assert PtrDType(dtypes.float32) == dtypes.float32
    assert not (PtrDType(dtypes.float32) != dtypes.float32)
    assert PtrDType(dtypes.float32) == PtrDType(dtypes.float32)
    assert not (PtrDType(dtypes.float32) != PtrDType(dtypes.float32))
    #assert PtrDType(dtypes.float32) != dtypes.float32
  def test_strs(self):
    if PtrDType is None: raise unittest.SkipTest("no PtrDType support")
    self.assertEqual(str(dtypes.imagef((1,2,4))), "dtypes.imagef((1, 2, 4))")
    self.assertEqual(str(PtrDType(dtypes.float32)), "ptr.dtypes.float")

class TestHelpers(unittest.TestCase):
  signed_ints = (dtypes.int8, dtypes.int16, dtypes.int32, dtypes.int64)
  uints = (dtypes.uint8, dtypes.uint16, dtypes.uint32, dtypes.uint64)
  floats = (dtypes.float16, dtypes.float32, dtypes.float64)

  @given(strat.sampled_from(signed_ints+uints), strat.integers(min_value=1, max_value=8))
  def test_is_int(self, dtype, amt):
    assert dtypes.is_int(dtype.vec(amt) if amt > 1 else dtype)
    assert not dtypes.is_float(dtype.vec(amt) if amt > 1 else dtype)

  @given(strat.sampled_from(uints), strat.integers(min_value=1, max_value=8))
  def test_is_unsigned_uints(self, dtype, amt):
    assert dtypes.is_unsigned(dtype.vec(amt) if amt > 1 else dtype)

  @given(strat.sampled_from(signed_ints), strat.integers(min_value=1, max_value=8))
  def test_is_unsigned_signed_ints(self, dtype, amt):
    assert not dtypes.is_unsigned(dtype.vec(amt) if amt > 1 else dtype)

  @given(strat.sampled_from(floats), strat.integers(min_value=1, max_value=8))
  def test_is_float(self, dtype, amt):
    assert dtypes.is_float(dtype.vec(amt) if amt > 1 else dtype)
    assert not dtypes.is_int(dtype.vec(amt) if amt > 1 else dtype)
    assert not dtypes.is_unsigned(dtype.vec(amt) if amt > 1 else dtype)

  def test_bf16_is_float(self):
    assert dtypes.is_float(dtypes.bfloat16)

  @given(strat.sampled_from([d for d in DTYPES_DICT.values() if dtypes.is_float(d) or dtypes.is_int(d)]), strat.integers(min_value=2, max_value=8))
  def test_scalar(self, dtype, amt):
    assert dtype.vec(amt).scalar() == dtype

class TestTypeSpec(unittest.TestCase):
  def setUp(self):
    self.old_default_int, self.old_default_float = dtypes.default_int, dtypes.default_float
  def tearDown(self):
    dtypes.default_int, dtypes.default_float = self.old_default_int, self.old_default_float

  def test_set_dtype_default(self):
    dtypes.default_int = dtypes.int16
    assert dtypes.default_int == dtypes.int16
    dtypes.default_int = dtypes.int64
    assert dtypes.default_int == dtypes.int64
    dtypes.default_int = dtypes.int32
    assert dtypes.default_int == dtypes.int32
    dtypes.default_float = dtypes.float16
    assert dtypes.default_float == dtypes.float16
    dtypes.default_float = dtypes.float64
    assert dtypes.default_float == dtypes.float64

  @given(strat.sampled_from([dtypes.int8,dtypes.int16,dtypes.int32,dtypes.int64]), strat.sampled_from([dtypes.float16,dtypes.float32,dtypes.float64]))
  def test_creation(self, default_int, default_float):
    dtypes.default_int, dtypes.default_float = default_int, default_float
    assert Tensor(True).dtype == dtypes.bool
    assert Tensor(None).dtype == dtypes.default_float
    assert Tensor(2).dtype == dtypes.default_int
    assert Tensor(2.34).dtype == dtypes.default_float
    assert Tensor([]).dtype == dtypes.default_float
    assert Tensor([1]).dtype == dtypes.default_int
    assert Tensor([1.1]).dtype == dtypes.default_float
    assert Tensor([0,1], dtype=dtypes.bfloat16).dtype == dtypes.bfloat16

    assert Tensor.eye(0).dtype == dtypes.default_float
    assert Tensor.eye(3).dtype == dtypes.default_float
    assert Tensor.eye(3, dtype=dtypes.float16).dtype == dtypes.float16
    assert Tensor.eye(3, dtype=dtypes.int64).dtype == dtypes.int64


  @given(strat.sampled_from([dtypes.int8,dtypes.int16,dtypes.int32,dtypes.int64]), strat.sampled_from([dtypes.float16,dtypes.float32,dtypes.float64]))
  def test_full(self, default_int, default_float):
    dtypes.default_int, dtypes.default_float = default_int, default_float

    assert Tensor.ones([2,3]).dtype == dtypes.default_float
    assert Tensor.zeros([2,3]).dtype == dtypes.default_float
    assert Tensor.full([2,3], 3.3).dtype == dtypes.default_float
    assert Tensor.full([2,3], 3).dtype == dtypes.default_int
    assert Tensor.full([2,3], True).dtype == dtypes.bool

    assert Tensor.zeros(3, 3).dtype == dtypes.default_float
    assert Tensor.zeros(3, 3, dtype=dtypes.float16).dtype == dtypes.float16
    assert Tensor.zeros(3, 3, dtype=dtypes.int64).dtype == dtypes.int64

    assert Tensor.ones(3, 3).dtype == dtypes.default_float
    assert Tensor.ones(3, 3, dtype=dtypes.float16).dtype == dtypes.float16
    assert Tensor.ones(3, 3, dtype=dtypes.int64).dtype == dtypes.int64

    assert Tensor.full((3, 3), 3).dtype == dtypes.default_int
    assert Tensor.full((3, 3), 3.0).dtype == dtypes.default_float
    assert Tensor.full((3, 3), 3, dtype=dtypes.float16).dtype == dtypes.float16
    assert Tensor.full((3, 3), 3, dtype=dtypes.int64).dtype == dtypes.int64

  def test_reduce_0d_default(self):
    assert Tensor.ones([2,3,0]).sum(2).dtype ==  dtypes.default_float
    assert Tensor.ones([2,3,0], dtype=dtypes.int).sum(2).dtype == dtypes.int

  @given(strat.sampled_from([dtypes.int8,dtypes.int16,dtypes.int32,dtypes.int64]), strat.sampled_from([dtypes.float16,dtypes.float32,dtypes.float64]))
  def test_arange(self, default_int, default_float):
    dtypes.default_int, dtypes.default_float = default_int, default_float

    assert Tensor.arange(5).dtype == dtypes.default_int
    assert Tensor.arange(5.0).dtype == dtypes.default_float
    assert Tensor.arange(5, dtype=dtypes.int16).dtype == dtypes.int16
    assert Tensor.arange(5, dtype=dtypes.int64).dtype == dtypes.int64
    assert Tensor.arange(5, dtype=dtypes.float16).dtype == dtypes.float16
    assert Tensor.arange(3, 9, 0.7).dtype == dtypes.default_float
    assert Tensor.arange(3, 8.5, 3).dtype == dtypes.default_float

  @unittest.skipIf(Device.DEFAULT == "WEBGPU", "WEBGPU doesn't follow the bool ops spec")
  @given(strat.sampled_from(core_dtypes), strat.sampled_from([operator.gt, operator.ge, operator.le, operator.lt, operator.eq, operator.ne]))
  def test_bool_ops(self, dtype, op):
    assert op(Tensor.rand(4, 4, dtype=dtype), Tensor.rand(4, 4, dtype=dtype)).dtype == dtypes.bool

  @given(strat.sampled_from(core_dtypes),
         strat.sampled_from([dtypes.int8,dtypes.int16,dtypes.int32,dtypes.int64]), strat.sampled_from([dtypes.float16,dtypes.float32,dtypes.float64]))
  def test_functions_return_index(self, dtype, default_int, default_float):
    dtypes.default_int, dtypes.default_float = default_int, default_float
    assert Tensor([0, 1], dtype=dtype).argmax().dtype == dtypes.default_int
    assert Tensor([0, 1], dtype=dtype).argmin().dtype == dtypes.default_int
    assert Tensor([0, 1], dtype=dtype).multinomial().dtype == dtypes.default_int

class TestTypePromotion(unittest.TestCase):
  @given(strat.sampled_from(core_dtypes))
  def test_self_promo_to_self(self, dtype):
    assert least_upper_dtype(dtype) == dtype
    assert least_upper_dtype(dtype, dtype) == dtype
    assert least_upper_dtype(dtype, dtype, dtype) == dtype

  @given(strat.sampled_from(core_dtypes), strat.sampled_from(core_dtypes))
  def test_promo_resulted_higher_than_inputs(self, dtype1, dtype2):
    result = least_upper_dtype(dtype1, dtype2)
    assert result >= dtype1 and result >= dtype2

  def test_dtype_promo(self):
    assert least_upper_dtype(dtypes.bool, dtypes.int8) == dtypes.int8
    assert least_upper_dtype(dtypes.int8, dtypes.uint8) == dtypes.int16
    assert least_upper_dtype(dtypes.uint8, dtypes.int16) == dtypes.int16
    assert least_upper_dtype(dtypes.int16, dtypes.uint16) == dtypes.int32
    assert least_upper_dtype(dtypes.uint16, dtypes.int32) == dtypes.int32
    assert least_upper_dtype(dtypes.int32, dtypes.uint32) == dtypes.int64
    assert least_upper_dtype(dtypes.uint32, dtypes.int64) == dtypes.int64
    # similar to jax but we don't use weak type
    assert least_upper_dtype(dtypes.int64, dtypes.uint64) == dtypes.float16
    assert least_upper_dtype(dtypes.float16, dtypes.float32) == dtypes.float32
    assert least_upper_dtype(dtypes.float32, dtypes.float64) == dtypes.float64

    assert least_upper_dtype(dtypes.bool, dtypes.float32) == dtypes.float32
    assert least_upper_dtype(dtypes.bool, dtypes.float64) == dtypes.float64
    assert least_upper_dtype(dtypes.float16, dtypes.int64) == dtypes.float16
    assert least_upper_dtype(dtypes.float16, dtypes.uint64) == dtypes.float16

  @given(strat.sampled_from(floats))
  def test_float_to_float(self, dt):
    assert least_upper_float(dt) == dt

class TestAutoCastType(unittest.TestCase):
  def setUp(self):
    self.old_default_int, self.old_default_float = dtypes.default_int, dtypes.default_float
  def tearDown(self):
    dtypes.default_int, dtypes.default_float = self.old_default_int, self.old_default_float

  @given(strat.sampled_from([d for d in DTYPES_DICT.values() if dtypes.is_int(d) and is_dtype_supported(d)]))
  def test_int_to_float_unary_func(self, dtype):
    for func in [
      lambda t: t.exp(),
      lambda t: t.exp2(),
      lambda t: t.log(),
      lambda t: t.log2(),
      lambda t: t.sqrt(),
      lambda t: t.rsqrt(),
      lambda t: t.sin(),
      lambda t: t.cos(),
      lambda t: t.tan(),
      lambda t: t.sigmoid(),
    ]:
      a = [2, 3, 4]
      # float16 can have larger precision errors
      np.testing.assert_allclose(func(Tensor(a, dtype=dtype)).numpy(), func(torch.tensor(a)), rtol=1e-3, atol=1e-3)

  @given(strat.sampled_from(core_dtypes))
  def test_broadcast_scalar(self, dt):
    assert (Tensor.rand(4, 4, dtype=dt) + 2.3).dtype == (dt if dtypes.is_float(dt) else dtypes.default_float)
    assert (Tensor.rand(4, 4, dtype=dt) + 2).dtype == (dt if dtypes.is_float(dt) or dtypes.is_int(dt) else dtypes.default_int)
    if Device.DEFAULT != "WEBGPU" and dt != dtypes.bool:
      assert (Tensor.rand(4, 4, dtype=dt) + True).dtype == dt

  def test_sum(self):
    assert (Tensor([0, 1], dtype=dtypes.bool)).sum().dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int8)).sum().dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int16)).sum().dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int32)).sum().dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int64)).sum().dtype == dtypes.int64
    assert (Tensor([0, 1], dtype=dtypes.uint8)).sum().dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint16)).sum().dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint32)).sum().dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint64)).sum().dtype == dtypes.uint64
    assert (Tensor([0, 1], dtype=dtypes.float16)).sum().dtype == dtypes.float16
    assert (Tensor([0, 1], dtype=dtypes.bfloat16)).sum().dtype == dtypes.bfloat16
    assert (Tensor([0, 1], dtype=dtypes.float32)).sum().dtype == dtypes.float32
    assert (Tensor([0, 1], dtype=dtypes.float64)).sum().dtype == dtypes.float64

  def test_cumsum(self):
    assert (Tensor([0, 1], dtype=dtypes.bool)).cumsum(0).dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int8)).cumsum(0).dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int16)).cumsum(0).dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int32)).cumsum(0).dtype == dtypes.int32
    assert (Tensor([0, 1], dtype=dtypes.int64)).cumsum(0).dtype == dtypes.int64
    assert (Tensor([0, 1], dtype=dtypes.uint8)).cumsum(0).dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint16)).cumsum(0).dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint32)).cumsum(0).dtype == dtypes.uint32
    assert (Tensor([0, 1], dtype=dtypes.uint64)).cumsum(0).dtype == dtypes.uint64
    assert (Tensor([0, 1], dtype=dtypes.float16)).cumsum(0).dtype == dtypes.float16
    assert (Tensor([0, 1], dtype=dtypes.bfloat16)).cumsum(0).dtype == dtypes.bfloat16
    assert (Tensor([0, 1], dtype=dtypes.float32)).cumsum(0).dtype == dtypes.float32
    assert (Tensor([0, 1], dtype=dtypes.float64)).cumsum(0).dtype == dtypes.float64

  @given(strat.sampled_from(core_dtypes), strat.sampled_from(core_dtypes))
  def test_matmul(self, dt1, dt2):
    assert (Tensor([0, 1], dtype=dt1) @ Tensor([0, 1], dtype=dt2)).dtype == least_upper_dtype(dt1, dt2)

  @staticmethod
  def check_where_alternate_input_other(input_, other, data_type):
    assert (Tensor([True, False]).where(input_, other)).dtype == data_type
    assert (Tensor([True, False]).where(other, input_)).dtype == data_type

  @given(strat.sampled_from(core_dtypes), strat.sampled_from(core_dtypes))
  def test_where_no_scalar(self, dt1, dt2):
    self.check_where_alternate_input_other(Tensor(2, dtype=dt1), Tensor(3, dtype=dt2), least_upper_dtype(dt1, dt2))

  @given(strat.sampled_from(core_dtypes))
  def test_where_one_scalar(self, dt):
    t = Tensor(2, dtype=dt)
    self.check_where_alternate_input_other(t, 3.2, (dt if dtypes.is_float(dt) else dtypes.default_float))
    self.check_where_alternate_input_other(t, 3, (dt if dtypes.is_float(dt) or dtypes.is_int(dt) else dtypes.default_int))
    self.check_where_alternate_input_other(t, True, dt)

  def test_where_two_scalars(self):
    self.check_where_alternate_input_other(3.1, 3.2, dtypes.default_float)
    self.check_where_alternate_input_other(3.1, 3, dtypes.default_float)
    self.check_where_alternate_input_other(3.1, True, dtypes.default_float)
    self.check_where_alternate_input_other(3, 2, dtypes.default_int)
    self.check_where_alternate_input_other(3, True, dtypes.default_int)
    self.check_where_alternate_input_other(False, True, dtypes.bool)

  @given(strat.sampled_from(core_dtypes), strat.sampled_from(core_dtypes))
  def test_maximum(self, dt1, dt2):
    assert Tensor([0, 1, 2], dtype=dt1).maximum(Tensor([2, 0, 5], dtype=dt2)).dtype == least_upper_dtype(dt1, dt2)

  @given(strat.sampled_from(core_dtypes))
  def test_maximum_const(self, dt):
    assert Tensor([1, 2], dtype=dt).maximum(3.1).dtype == (dt if dtypes.is_float(dt) else dtypes.default_float)
    assert Tensor([1, 2], dtype=dt).maximum(3).dtype == (dt if dtypes.is_float(dt) or dtypes.is_int(dt) else dtypes.default_int)
    assert Tensor([1, 2], dtype=dt).maximum(True).dtype == dt

  def test_div(self):
    assert (Tensor([1, 2], dtype=dtypes.int32) / Tensor([2, 2], dtype=dtypes.int32)).dtype == dtypes.default_float
    assert (Tensor([1, 2], dtype=dtypes.int16) / Tensor([2, 2], dtype=dtypes.int32)).dtype == dtypes.default_float
    assert (Tensor([1, 2], dtype=dtypes.float32) / Tensor([2, 2], dtype=dtypes.float16)).dtype == dtypes.float32
    assert (Tensor([1, 2], dtype=dtypes.int32) / Tensor([2, 2], dtype=dtypes.float16)).dtype == dtypes.float16

  def test_div_const(self):
    assert (Tensor([1, 2], dtype=dtypes.int32) / 2).dtype == dtypes.default_float
    assert (Tensor([1, 2], dtype=dtypes.int32) / 2.0).dtype == dtypes.default_float
    assert (Tensor([1, 2], dtype=dtypes.float16) / 2).dtype == dtypes.float16
    assert (Tensor([1, 2], dtype=dtypes.float16) / 2.0).dtype == dtypes.float16

if __name__ == '__main__':
  unittest.main()