track type aliases at top level

slither/core/compilation_unit.py

@@ -18,6 +18,7 @@ from slither.core.declarations.enum_top_level import EnumTopLevel
 from slither.core.declarations.function_top_level import FunctionTopLevel
 from slither.core.declarations.using_for_top_level import UsingForTopLevel
 from slither.core.declarations.structure_top_level import StructureTopLevel
+from slither.core.solidity_types.type_alias import TypeAliasTopLevel
 from slither.core.scope.scope import FileScope
 from slither.core.variables.state_variable import StateVariable
 from slither.core.variables.top_level_variable import TopLevelVariable
@@ -46,6 +47,7 @@ class SlitherCompilationUnit(Context):
         self._pragma_directives: List[Pragma] = []
         self._import_directives: List[Import] = []
         self._custom_errors: List[CustomError] = []
+        self._user_defined_value_types: Dict[str, TypeAliasTopLevel] = {}
 
         self._all_functions: Set[Function] = set()
         self._all_modifiers: Set[Modifier] = set()
@@ -215,6 +217,10 @@ class SlitherCompilationUnit(Context):
     def custom_errors(self) -> List[CustomError]:
         return self._custom_errors
 
+    @property
+    def user_defined_value_types(self) -> Dict[str, TypeAliasTopLevel]:
+        return self._user_defined_value_types
+
     # endregion
     ###################################################################################
     ###################################################################################

slither/solc_parsing/slither_compilation_unit_solc.py

@@ -330,6 +330,7 @@ class SlitherCompilationUnitSolc(CallerContextExpression):
 
                 user_defined_type = TypeAliasTopLevel(original_type, alias, scope)
                 user_defined_type.set_offset(top_level_data["src"], self._compilation_unit)
+                self._compilation_unit.user_defined_value_types[alias] = user_defined_type
                 scope.user_defined_types[alias] = user_defined_type
 
             else:

slither/solc_parsing/solidity_types/type_parsing.py

@@ -243,7 +243,7 @@ def parse_type(
             sl = caller_context.compilation_unit
             next_context = caller_context
             renaming = {}
-            user_defined_types = {}
+            user_defined_types = sl.user_defined_value_types
         else:
             assert isinstance(caller_context, FunctionSolc)
             sl = caller_context.underlying_function.compilation_unit