fix(mge/module): fix non-str key error of dict in module

GitOrigin-RevId: f82cd48230b2cfcf9c8da7442d3eb1e4bdbe3aee

python_module/megengine/module/module.py

@@ -18,17 +18,25 @@ logger = get_logger(__name__)
 
 
 def _expand_structure(key, obj):
-    if isinstance(obj, (list, tuple, dict)):
+    if isinstance(obj, (Tensor, Module)):
+        return [(key, obj)]
+    elif isinstance(obj, (list, tuple, dict)):
         ret = []
         if isinstance(obj, dict):
             targets = ((k, obj[k]) for k in sorted(obj))
         else:
             targets = ((str(k), v) for k, v in enumerate(obj))
         for k, o in targets:
-            ret.extend(_expand_structure(key + "." + k, o))
+            sub_ret = _expand_structure(k, o)
+            if sub_ret and not isinstance(k, str):
+                raise AssertionError(
+                    "keys for Tensor and Module must be str, error key: {}".format(k)
+                )
+            for kt, vt in sub_ret:
+                ret.extend([(key + "." + kt, vt)])
         return ret
     else:
-        return [(key, obj)]
+        return []
 
 
 def _is_parameter(obj):
@@ -72,11 +80,11 @@ class Module(metaclass=ABCMeta):
         predicate: Callable[[Any], bool] = lambda _: True,
         seen: Optional[Set[int]] = None
     ) -> Union[Iterable[Any], Iterable[Tuple[str, Any]]]:
-        """Scans the module object and returns an iterable for the attributes that
-        agree with the ``predicate``. For multiple calls of this function with same
-        arguments, the order of objects within the returned iterable is guaranteed to be
-        identical, as long as all the involved module objects' ``__dict__`` does not
-        change thoughout those calls.
+        """Scans the module object and returns an iterable for the :class:`~.Tensor`
+        and :class:`~.Module` attributes that agree with the ``predicate``. For multiple
+        calls of this function with same arguments, the order of objects within the
+        returned iterable is guaranteed to be identical, as long as all the involved
+        module objects' ``__dict__`` does not change thoughout those calls.
 
         :param recursive: Whether to recursively scan all the submodules.
         :param with_key: Whether to yield keys along with yielded objects.

python_module/test/unit/module/test_module.py

@@ -14,7 +14,7 @@ import pytest
 from helpers import MLP
 
 import megengine as mge
-from megengine.core import Buffer, Parameter, tensor
+from megengine.core import Buffer, Parameter, Tensor, tensor
 from megengine.module import BatchNorm1d, BatchNorm2d, Conv2d, Module, Sequential
 from megengine.test import assertTensorClose
 
@@ -139,6 +139,7 @@ class MyModule2(Module):
         def __init__(self):
             super().__init__()
             self.bn = BatchNorm2d(4)
+            self.test_bool_key = {True: 1, False: 0}
 
         def forward(self, x):
             x = self.bn(x)
@@ -148,7 +149,7 @@ class MyModule2(Module):
         self.bn = BatchNorm2d(4)
         self.a = [
             BatchNorm2d(4),
-            {"x": BatchNorm2d(4), "y": [BatchNorm2d(4), self.InnerModule()]},
+            {"x": BatchNorm2d(4), "y": [BatchNorm2d(4), self.InnerModule()], "z": 0},
             (self.InnerModule(),),
         ]
 
@@ -171,6 +172,14 @@ def test_expand_structure():
     ]
 
 
+def test_flatten_others():
+    def be_others(obj):
+        return not isinstance(obj, (Tensor, Module))
+
+    m = MyModule2()
+    assert len(list(m._flatten(with_key=True, predicate=be_others))) == 0
+
+
 def test_flatten_with_parent():
     m = MyModule2()
     assert list(m.named_modules(with_parent=True)) == [
@@ -251,6 +260,23 @@ def test_state_dict():
             mlp1.load_state_dict(state_dict)
 
 
+class AssertModule(Module):
+    def __init__(self):
+        super().__init__()
+        self.error_tensor_key = {True: tensor(), False: 0}
+
+    def forward(self, x):
+        return x
+
+
+def test_assert_message():
+    m = AssertModule()
+    with pytest.raises(
+        AssertionError, match="keys for Tensor and Module must be str, error key: True"
+    ):
+        list(m._flatten())
+
+
 class Simple(Module):
     def __init__(self):
         super().__init__()