fix: replace ast.Str and drop astor

docs/prerequisites.md

@@ -4,7 +4,7 @@ This page describes the system prerequisites needed to run SQLMesh and provides
 
 ## SQLMesh prerequisites
 
-You'll need Python 3.8 or higher to use SQLMesh. You can check your python version by running the following command:
+You'll need Python 3.9 or higher to use SQLMesh. You can check your python version by running the following command:
 ```bash
 python3 --version
 ```

pyproject.toml

@@ -7,7 +7,6 @@ authors = [{ name = "SQLMesh Contributors" }]
 license = { file = "LICENSE" }
 requires-python = ">= 3.9"
 dependencies = [
-    "astor",
     "click",
     "croniter",
     "duckdb>=0.10.0,!=0.10.3",
@@ -198,7 +197,6 @@ disable_error_code = "annotation-unchecked"
 [[tool.mypy.overrides]]
 module = [
     "api.*",
-    "astor.*",
     "IPython.*",
     "hyperscript.*",
     "py.*",

sqlmesh/core/model/common.py

@@ -4,7 +4,6 @@
 import typing as t
 from pathlib import Path
 
-from astor import to_source
 from difflib import get_close_matches
 from sqlglot import exp
 from sqlglot.helper import ensure_list
@@ -387,7 +386,7 @@ def get_first_arg(keyword_arg_name: str) -> t.Any:
                         )
 
                     try:
-                        expression = to_source(first_arg)
+                        expression = ast.unparse(t.cast(ast.expr, first_arg))
                         return eval(expression, env, local_env)
                     except Exception:
                         if strict_resolution:

sqlmesh/utils/metaprogramming.py

@@ -17,8 +17,6 @@
 from numbers import Number
 from pathlib import Path
 
-from astor import to_source
-
 from sqlmesh.core import constants as c
 from sqlmesh.utils import format_exception, unique
 from sqlmesh.utils.errors import SQLMeshError
@@ -267,14 +265,19 @@ def normalize_source(obj: t.Any) -> str:
 
             # remove docstrings
             body = node.body
-            if body and isinstance(body[0], ast.Expr) and isinstance(body[0].value, ast.Str):
+            if (
+                body
+                and isinstance(body[0], ast.Expr)
+                and isinstance(body[0].value, ast.Constant)
+                and isinstance(body[0].value.value, str)
+            ):
                 node.body = body[1:]
 
             # remove function return type annotation
             if isinstance(node, ast.FunctionDef):
                 node.returns = None
 
-    return to_source(root_node).strip()
+    return ast.unparse(root_node).strip()
 
 
 def build_env(

tests/utils/test_metaprogramming.py

@@ -220,8 +220,7 @@ def closure() -> int:
 def test_normalize_source() -> None:
     assert (
         normalize_source(main_func)
-        == """def main_func(y: int, foo=exp.true(), *, bar=expressions.Literal.number(1) + 2
-    ):
+        == """def main_func(y: int, foo=exp.true(), *, bar=expressions.Literal.number(1) + 2):
     sqlglot.parse_one('1')
     MyClass(47)
     DataClass(x=y)
@@ -271,8 +270,7 @@ def test_serialize_env() -> None:
             name="main_func",
             alias="MAIN",
             path="test_metaprogramming.py",
-            payload="""def main_func(y: int, foo=exp.true(), *, bar=expressions.Literal.number(1) + 2
-    ):
+            payload="""def main_func(y: int, foo=exp.true(), *, bar=expressions.Literal.number(1) + 2):
     sqlglot.parse_one('1')
     MyClass(47)
     DataClass(x=y)
@@ -370,7 +368,7 @@ def sample_context_manager():
         "my_lambda": Executable(
             name="my_lambda",
             path="test_metaprogramming.py",
-            payload="my_lambda = lambda : print('z')",
+            payload="my_lambda = lambda: print('z')",
         ),
         "normalize_model_name": Executable(
             payload="from sqlmesh.core.dialect import normalize_model_name",