Introduce ASTBuilder mixin to simplify and reduce verbosity in AST construction, refactor language_generation.py to leverage the new mixin, and consolidate feature creation logic.

Author: ftomassetti

src/lionweb/generation/ASTBuilder.py

@@ -0,0 +1,38 @@
+import ast
+
+class ASTBuilder:
+    """Helper mixin to reduce ast verbosity."""
+
+    def name(self, id: str, ctx=None) -> ast.Name:
+        return ast.Name(id=id, ctx=ctx or ast.Load())
+
+    def const(self, value) -> ast.Constant:
+        return ast.Constant(value=value)
+
+    def attr(self, value, attr: str, ctx=None) -> ast.Attribute:
+        # value can be a string (implies a Name node) or an AST node
+        if isinstance(value, str):
+            value = self.name(value)
+        return ast.Attribute(value=value, attr=attr, ctx=ctx or ast.Load())
+
+    def call(self, func, args=None, keywords=None) -> ast.Call:
+        """Creates a function call.
+        'func' can be a string (function name) or an AST node.
+        'keywords' is a dict of {arg_name: ast_node}.
+        """
+        if isinstance(func, str):
+            func = self.name(func)
+
+        ast_keywords = []
+        if keywords:
+            for k, v in keywords.items():
+                if v is None: continue # Skip None values
+                ast_keywords.append(ast.keyword(arg=k, value=v))
+
+        return ast.Call(func=func, args=args or [], keywords=ast_keywords)
+
+    def assign(self, target_id: str, value) -> ast.Assign:
+        return ast.Assign(
+            targets=[self.name(target_id, ctx=ast.Store())],
+            value=value
+        )