[POC] fix: Python 3.12 ast deprecation warnings (pending removal in 3.14)

.gitignore

@@ -10,3 +10,6 @@ _build
 .benchmarks
 .hypothesis
 build
+
+# pyenv
+.python-version

src/fluent_compiler/codegen.py

@@ -2,11 +2,11 @@
 Utilities for doing Python code generation
 """
 
+import ast
 import keyword
 import platform
 import re
 
-from . import ast_compat as ast
 from .utils import allowable_keyword_arg_name, allowable_name
 
 # This module provides simple utilities for building up Python source code. It
@@ -406,7 +406,7 @@ def as_ast(self):
             def add_lineno(node):
                 node.lineno = self.source.row
 
-            ast.traverse(func_def, add_lineno)
+            traverse(func_def, add_lineno)
         return func_def
 
     def add_return(self, value):
@@ -531,7 +531,7 @@ def __init__(self, string_value):
         self.string_value = string_value
 
     def as_ast(self):
-        return ast.Str(
+        return ast.Constant(
             self.string_value,
             kind=None,  # 3.8, indicates no prefix, needed only for tests
             **DEFAULT_AST_ARGS,
@@ -552,7 +552,7 @@ def __init__(self, number):
         self.type = type(number)
 
     def as_ast(self):
-        return ast.Num(n=self.number, **DEFAULT_AST_ARGS)
+        return ast.Constant(value=self.number, **DEFAULT_AST_ARGS)
 
     def __repr__(self):
         return f"Number({repr(self.number)})"
@@ -729,7 +729,7 @@ def as_ast(self):
                     ast.keyword(
                         arg=None,
                         value=ast.Dict(
-                            keys=[ast.Str(k, kind=None, **DEFAULT_AST_ARGS) for k in kwarg_names],
+                            keys=[ast.Constant(k, kind=None, **DEFAULT_AST_ARGS) for k in kwarg_names],
                             values=[v.as_ast() for v in kwarg_values],
                             **DEFAULT_AST_ARGS,
                         ),
@@ -859,6 +859,14 @@ def rewriter(node):
     return codegen_ast
 
 
+def traverse(ast_node, func):
+    """
+    Apply 'func' to ast_node (which is `ast.*` object)
+    """
+    for node in ast.walk(ast_node):
+        func(node)
+
+
 def rewriting_traverse(node, func):
     """
     Apply 'func' to node and all sub PythonAst nodes