[Feature] example_data for NonTensor spec

ghstack-source-id: 6fe5d82
Pull Request resolved: #2698

Author: Vincent Moens

test/test_specs.py

@@ -1402,12 +1402,13 @@ def test_multionehot(self, shape1, shape2):
         assert spec2.zero().shape == spec2.shape
 
     def test_non_tensor(self):
-        spec = NonTensor((3, 4), device="cpu")
+        spec = NonTensor((3, 4), device="cpu", example_data="example_data")
         assert (
             spec.expand(2, 3, 4)
             == spec.expand((2, 3, 4))
-            == NonTensor((2, 3, 4), device="cpu")
+            == NonTensor((2, 3, 4), device="cpu", example_data="example_data")
         )
+        assert spec.expand(2, 3, 4).example_data == "example_data"
 
     @pytest.mark.parametrize("shape1", [None, (), (5,)])
     @pytest.mark.parametrize("shape2", [(), (10,)])
@@ -1607,9 +1608,10 @@ def test_multionehot(
         assert spec is not spec.clone()
 
     def test_non_tensor(self):
-        spec = NonTensor(shape=(3, 4), device="cpu")
+        spec = NonTensor(shape=(3, 4), device="cpu", example_data="example_data")
         assert spec.clone() == spec
         assert spec.clone() is not spec
+        assert spec.clone().example_data == "example_data"
 
     @pytest.mark.parametrize("shape1", [None, (), (5,)])
     def test_onehot(
@@ -1840,9 +1842,10 @@ def test_multionehot(
             spec.unbind(-1)
 
     def test_non_tensor(self):
-        spec = NonTensor(shape=(3, 4), device="cpu")
+        spec = NonTensor(shape=(3, 4), device="cpu", example_data="example_data")
         assert spec.unbind(1)[0] == spec[:, 0]
         assert spec.unbind(1)[0] is not spec[:, 0]
+        assert spec.unbind(1)[0].example_data == "example_data"
 
     @pytest.mark.parametrize("shape1", [(5,), (5, 6)])
     def test_onehot(
@@ -2001,8 +2004,9 @@ def test_multionehot(self, shape1, device):
         assert spec.to(device).device == device
 
     def test_non_tensor(self, device):
-        spec = NonTensor(shape=(3, 4), device="cpu")
+        spec = NonTensor(shape=(3, 4), device="cpu", example_data="example_data")
         assert spec.to(device).device == device
+        assert spec.to(device).example_data == "example_data"
 
     @pytest.mark.parametrize("shape1", [(5,), (5, 6)])
     def test_onehot(self, shape1, device):
@@ -2262,13 +2266,14 @@ def test_stack_multionehot_zero(self, shape, stack_dim):
         assert r.shape == c.shape
 
     def test_stack_non_tensor(self, shape, stack_dim):
-        spec0 = NonTensor(shape=shape, device="cpu")
-        spec1 = NonTensor(shape=shape, device="cpu")
+        spec0 = NonTensor(shape=shape, device="cpu", example_data="example_data")
+        spec1 = NonTensor(shape=shape, device="cpu", example_data="example_data")
         new_spec = torch.stack([spec0, spec1], stack_dim)
         shape_insert = list(shape)
         shape_insert.insert(stack_dim, 2)
         assert new_spec.shape == torch.Size(shape_insert)
         assert new_spec.device == torch.device("cpu")
+        assert new_spec.example_data == "example_data"
 
     def test_stack_onehot(self, shape, stack_dim):
         n = 5
@@ -3642,10 +3647,18 @@ def test_expand(self):
 
 class TestNonTensorSpec:
     def test_sample(self):
-        nts = NonTensor(shape=(3, 4))
+        nts = NonTensor(shape=(3, 4), example_data="example_data")
         assert nts.one((2,)).shape == (2, 3, 4)
         assert nts.rand((2,)).shape == (2, 3, 4)
         assert nts.zero((2,)).shape == (2, 3, 4)
+        assert nts.one((2,)).data == "example_data"
+        assert nts.rand((2,)).data == "example_data"
+        assert nts.zero((2,)).data == "example_data"
+
+    def test_example_data_ineq(self):
+        nts0 = NonTensor(shape=(3, 4), example_data="example_data")
+        nts1 = NonTensor(shape=(3, 4), example_data="example_data 2")
+        assert nts0 != nts1
 
 
 @pytest.mark.skipif(not torch.cuda.is_available(), reason="not cuda device")

torchrl/data/tensor_specs.py

@@ -2452,11 +2452,14 @@ class NonTensor(TensorSpec):
     (same will go for :meth:`.zero` and :meth:`.one`).
     """
 
+    example_data: Any = None
+
     def __init__(
         self,
         shape: Union[torch.Size, int] = _DEFAULT_SHAPE,
         device: Optional[DEVICE_TYPING] = None,
         dtype: torch.dtype | None = None,
+        example_data: Any = None,
         **kwargs,
     ):
         if isinstance(shape, int):
@@ -2467,6 +2470,12 @@ def __init__(
         super().__init__(
             shape=shape, space=None, device=device, dtype=dtype, domain=domain, **kwargs
         )
+        self.example_data = example_data
+
+    def __eq__(self, other):
+        eq = super().__eq__(other)
+        eq = eq & (self.example_data == getattr(other, "example_data", None))
+        return eq
 
     def cardinality(self) -> Any:
         raise RuntimeError("Cannot enumerate a NonTensorSpec.")
@@ -2485,30 +2494,46 @@ def to(self, dest: Union[torch.dtype, DEVICE_TYPING]) -> NonTensor:
             dest_device = torch.device(dest)
         if dest_device == self.device and dest_dtype == self.dtype:
             return self
-        return self.__class__(shape=self.shape, device=dest_device, dtype=None)
+        return self.__class__(
+            shape=self.shape,
+            device=dest_device,
+            dtype=None,
+            example_data=self.example_data,
+        )
 
     def clone(self) -> NonTensor:
-        return self.__class__(shape=self.shape, device=self.device, dtype=self.dtype)
+        return self.__class__(
+            shape=self.shape,
+            device=self.device,
+            dtype=self.dtype,
+            example_data=self.example_data,
+        )
 
     def rand(self, shape=None):
         if shape is None:
             shape = ()
         return NonTensorData(
-            data=None, batch_size=(*shape, *self._safe_shape), device=self.device
+            data=self.example_data,
+            batch_size=(*shape, *self._safe_shape),
+            device=self.device,
         )
 
     def zero(self, shape=None):
         if shape is None:
             shape = ()
         return NonTensorData(
-            data=None, batch_size=(*shape, *self._safe_shape), device=self.device
+            data=self.example_data,
+            batch_size=(*shape, *self._safe_shape),
+            device=self.device,
         )
 
     def one(self, shape=None):
         if shape is None:
             shape = ()
         return NonTensorData(
-            data=None, batch_size=(*shape, *self._safe_shape), device=self.device
+            data=self.example_data,
+            batch_size=(*shape, *self._safe_shape),
+            device=self.device,
         )
 
     def is_in(self, val: Any) -> bool:
@@ -2533,23 +2558,46 @@ def expand(self, *shape):
             raise ValueError(
                 f"The last elements of the expanded shape must match the current one. Got shape={shape} while self.shape={self.shape}."
             )
-        return self.__class__(shape=shape, device=self.device, dtype=None)
+        return self.__class__(
+            shape=shape, device=self.device, dtype=None, example_data=self.example_data
+        )
+
+    def unsqueeze(self, dim: int) -> NonTensor:
+        unsq = super().unsqueeze(dim=dim)
+        unsq.example_data = self.example_data
+        return unsq
+
+    def squeeze(self, dim: int | None = None) -> NonTensor:
+        sq = super().squeeze(dim=dim)
+        sq.example_data = self.example_data
+        return sq
 
     def _reshape(self, shape):
-        return self.__class__(shape=shape, device=self.device, dtype=self.dtype)
+        return self.__class__(
+            shape=shape,
+            device=self.device,
+            dtype=self.dtype,
+            example_data=self.example_data,
+        )
 
     def _unflatten(self, dim, sizes):
         shape = torch.zeros(self.shape, device="meta").unflatten(dim, sizes).shape
         return self.__class__(
             shape=shape,
             device=self.device,
             dtype=self.dtype,
+            example_data=self.example_data,
         )
 
     def __getitem__(self, idx: SHAPE_INDEX_TYPING):
         """Indexes the current TensorSpec based on the provided index."""
         indexed_shape = _size(_shape_indexing(self.shape, idx))
-        return self.__class__(shape=indexed_shape, device=self.device, dtype=self.dtype)
+        return self.__class__(
+            shape=indexed_shape,
+            device=self.device,
+            dtype=self.dtype,
+            example_data=self.example_data,
+        )
 
     def unbind(self, dim: int = 0):
         orig_dim = dim
@@ -2565,6 +2613,7 @@ def unbind(self, dim: int = 0):
                 shape=shape,
                 device=self.device,
                 dtype=self.dtype,
+                example_data=self.example_data,
             )
             for i in range(self.shape[dim])
         )