optimized SyntaxTree class

src/ytdl_sub/script/parser.py

@@ -605,7 +605,7 @@ def parse(
         name=name,
         custom_function_names=custom_function_names,
         variable_names=variable_names,
-    ).ast
+    ).ast.maybe_resolvable_casted()
 
 
 # pylint: enable=invalid-name

src/ytdl_sub/script/types/syntax_tree.py

@@ -47,13 +47,25 @@ class SyntaxTree(VariableDependency):
         -------
         A resolvable if the AST contains a single type that is resolvable. None otherwise.
         """
-        if len(self.ast) == 1 and isinstance(self.ast[0], Resolvable):
-            return self.ast[0]
         return None
 
+    def maybe_resolvable_casted(self) -> "SyntaxTree":
+        """
+        Returns
+        -------
+        Optimized SyntaxTree if its deemed resolvable
+        """
+        if len(self.ast) == 1 and isinstance(self.ast[0], Resolvable):
+            return ResolvedSyntaxTree(self.ast)
+        return self
+
 
 @dataclass(frozen=True)
 class ResolvedSyntaxTree(SyntaxTree):
+    """
+    SyntaxTree with optimized helper functions if it's known to be resolved.
+    """
+
     def resolve(
         self,
         resolved_variables: Dict[Variable, Resolvable],