fix: Track "unwrapped" types during routine resolution

src/typelib/graph.py

@@ -50,9 +50,6 @@ def static_order(
     """
     # We want to leverage the cache if possible, hence the recursive call.
     #   Shouldn't actually recurse more than once or twice.
-    if inspection.istypealiastype(t):
-        value = inspection.unwrap(t)
-        return static_order(value)
     if isinstance(t, (str, refs.ForwardRef)):
         ref = refs.forwardref(t) if isinstance(t, str) else t
         t = refs.evaluate(ref)
@@ -80,8 +77,6 @@ def itertypes(
         [`static_order`][typelib.graph.static_order] instead of
         [`itertypes`][typelib.graph.itertypes].
     """
-    if inspection.istypealiastype(t):
-        t = inspection.unwrap(t)
     if isinstance(t, (str, refs.ForwardRef)):  # pragma: no cover
         ref = refs.forwardref(t) if isinstance(t, str) else t
         t = refs.evaluate(ref)
@@ -113,33 +108,31 @@ def get_type_graph(t: type) -> graphlib.TopologicalSorter[TypeNode]:
         resolve one level deep on each attempt, otherwise we will find ourselves stuck
         in a closed loop which never terminates (infinite recursion).
     """
-    if inspection.istypealiastype(t):
-        t = inspection.unwrap(t)
-
     graph: graphlib.TopologicalSorter = graphlib.TopologicalSorter()
-    root = TypeNode(t)
+    u = inspection.unwrap(t)
+    root = TypeNode(t, u)
     stack = collections.deque([root])
     visited = {root.type}
     while stack:
         parent = stack.popleft()
-        if inspection.isliteral(parent.type):
+        parent_unwrapped = inspection.unwrap(parent.type)
+        if inspection.isliteral(parent_unwrapped):
             graph.add(parent)
             continue
 
         predecessors = []
-        for var, child in _level(parent.type):
+        for var, child in _level(parent_unwrapped):
             # If no type was provided, there's no reason to do further processing.
             if child in (constants.empty, typing.Any):
                 continue
-            if inspection.istypealiastype(child):
-                child = inspection.unwrap(child)
 
+            unwrapped = inspection.unwrap(child)
             # Only subscripted generics or non-stdlib types can be cyclic.
             #   i.e., we may get `str` or `datetime` any number of times,
             #   that's not cyclic, so we can just add it to the graph.
-            is_visited = child in visited
-            is_subscripted = inspection.issubscriptedgeneric(child)
-            is_stdlib = inspection.isstdlibtype(child)
+            is_visited = child in visited or unwrapped in visited
+            is_subscripted = inspection.issubscriptedgeneric(unwrapped)
+            is_stdlib = inspection.isstdlibtype(unwrapped)
             can_be_cyclic = is_subscripted or is_stdlib is False
             # We detected a cyclic type,
             #   wrap in a ForwardRef and don't add it to the stack
@@ -155,10 +148,13 @@ def get_type_graph(t: type) -> graphlib.TopologicalSorter[TypeNode]:
                 ref = refs.forwardref(
                     refname, is_argument=is_argument, module=module, is_class=is_class
                 )
-                node = TypeNode(ref, var=var, cyclic=True)
+                uref = refs.forwardref(
+                    unwrapped, is_argument=is_argument, module=module, is_class=is_class
+                )
+                node = TypeNode(ref, uref, var=var, cyclic=True)
             # Otherwise, add the type to the stack and track that it's been seen.
             else:
-                node = TypeNode(type=child, var=var)
+                node = TypeNode(type=child, unwrapped=unwrapped, var=var)
                 visited.add(node.type)
                 stack.append(node)
             # Flag the type as a "predecessor" of the parent type.
@@ -177,11 +173,17 @@ class TypeNode:
 
     type: typing.Any
     """The type annotation for this node."""
+    unwrapped: typing.Any | None = None
+    """The unwrapped type annotation for this node."""
     var: str | None = None
     """The variable or parameter name associated to the type annotation for this node."""
     cyclic: bool = dataclasses.field(default=False, hash=False, compare=False)
     """Whether this type annotation is cyclic."""
 
+    def __post_init__(self):
+        if self.unwrapped is None:
+            self.unwrapped = self.type
+
 
 def _level(t: typing.Any) -> typing.Iterable[tuple[str | None, type]]:
     args = inspection.args(t)

src/typelib/marshals/api.py

@@ -54,6 +54,7 @@ def marshaller(
     root = nodes[-1]
     for node in nodes:
         context[node.type] = _get_unmarshaller(node, context=context)
+        context[node.unwrapped] = context[node.type]
 
     return context[root.type]
 
@@ -66,10 +67,12 @@ def _get_unmarshaller(  # type: ignore[return]
         return context[node.type]
 
     for check, unmarshaller_cls in _HANDLERS.items():
-        if check(node.type):
-            return unmarshaller_cls(node.type, context=context, var=node.var)
+        if check(node.unwrapped):
+            return unmarshaller_cls(node.unwrapped, context=context, var=node.var)
 
-    return routines.StructuredTypeMarshaller(node.type, context=context, var=node.var)
+    return routines.StructuredTypeMarshaller(
+        node.unwrapped, context=context, var=node.var
+    )
 
 
 class DelayedMarshaller(routines.AbstractMarshaller[T]):

src/typelib/py/inspection.py

@@ -573,7 +573,7 @@ def isoptionaltype(obj: type[_OT]) -> compat.TypeIs[type[tp.Optional[_OT]]]:
     tname = name(origin(obj))
     nullarg = next((a for a in args if a in (type(None), None)), ...)
     isoptional = tname == "Optional" or (
-        nullarg is not ... and tname in ("Union", "Uniontype", "Literal")
+        nullarg is not ... and tname in ("Union", "UnionType", "Literal")
     )
     return isoptional
 

src/typelib/unmarshals/api.py

@@ -48,6 +48,7 @@ def unmarshaller(
     root = nodes[-1]
     for node in nodes:
         context[node.type] = _get_unmarshaller(node, context=context)
+        context[node.unwrapped] = context[node.type]
 
     return context[root.type]
 
@@ -60,10 +61,12 @@ def _get_unmarshaller(  # type: ignore[return]
         return context[node.type]
 
     for check, unmarshaller_cls in _HANDLERS.items():
-        if check(node.type):
-            return unmarshaller_cls(node.type, context=context, var=node.var)
+        if check(node.unwrapped):
+            return unmarshaller_cls(node.unwrapped, context=context, var=node.var)
 
-    return routines.StructuredTypeUnmarshaller(node.type, context=context, var=node.var)
+    return routines.StructuredTypeUnmarshaller(
+        node.unwrapped, context=context, var=node.var
+    )
 
 
 class DelayedUnmarshaller(routines.AbstractUnmarshaller[T]):

tests/models.py

@@ -99,3 +99,8 @@ class NestedTypeAliasType:
 RecursiveAlias = compat.TypeAliasType(
     "RecursiveAlias", "dict[str, RecursiveAlias | ValueAlias]"
 )
+
+ScalarValue = compat.TypeAliasType("ScalarValue", "int | float | str | bool | None")
+Record = compat.TypeAliasType(
+    "Record", "dict[str, list[Record] | list[ScalarValue] | Record | ScalarValue]"
+)

tests/unit/marshals/test_routines.py

@@ -10,7 +10,6 @@
 
 import pytest
 
-from typelib import graph
 from typelib.marshals import routines
 
 from tests import models
@@ -405,12 +404,8 @@ def test_fixed_tuple_marshaller(
 @pytest.mark.suite(
     context=dict(
         given_context={
-            graph.TypeNode(int, var="value"): routines.IntegerMarshaller(
-                int, {}, var="value"
-            ),
-            graph.TypeNode(str, var="field"): routines.StringMarshaller(
-                str, {}, var="field"
-            ),
+            int: routines.IntegerMarshaller(int, {}, var="value"),
+            str: routines.StringMarshaller(str, {}, var="field"),
         },
         expected_output=dict(field="data", value=1),
     ),

tests/unit/test_graph.py

@@ -94,7 +94,7 @@ class NoTypes:
         given_type=models.NestedTypeAliasType,
         expected_nodes=[
             graph.TypeNode(type=int),
-            graph.TypeNode(type=list[int], var="alias"),
+            graph.TypeNode(type=models.ListAlias, unwrapped=list[int], var="alias"),
             graph.TypeNode(type=NestedTypeAliasType),
         ],
     ),