Remove astor dependency

Python 3.8 required us to use a library to print the generated Python
AST into Python source files.  Since we dropped the support for Python
3.8 (and 3.9) with 0bfb66a we can now
simply us the `unparse` function from Python's AST library that was
introduced in Python 3.9.

This change removes all `astor`-related code and makes the necessary
changes to use Python's `ast.unparse`.

docs/requirements.txt

@@ -1,6 +1,5 @@
 sphinx==4.4.0
 sphinx-autodoc-typehints==1.16.0
-astor==0.8.1
 simple-parsing==0.0.18
 bytecode==0.13.0
 typing_inspect==0.7.1

pynguin/generation/export/abstractexporter.py

@@ -13,8 +13,6 @@
 from pathlib import Path
 from typing import TYPE_CHECKING
 
-import astor
-
 import pynguin.testcase.testcase_to_ast as tc_to_ast
 
 if TYPE_CHECKING:
@@ -97,6 +95,7 @@ def __create_function_node(
                 defaults=[],
                 vararg=None,
                 kwarg=None,
+                posonlyargs=[],
                 kwonlyargs=[],
                 kw_defaults=[],
             ),
@@ -118,4 +117,4 @@ def _save_ast_to_file(path: str | os.PathLike, module: ast.Module) -> None:
         target.parent.mkdir(parents=True, exist_ok=True)
         with target.open(mode="w", encoding="UTF-8") as file:
             file.write("# Automatically generated by Pynguin.\n")
-            file.write(astor.to_source(module))
+            file.write(ast.unparse(ast.fix_missing_locations(module)))

pynguin/generation/export/pytestexporter.py

@@ -31,5 +31,5 @@ def export_sequences(self, path: str | os.PathLike, test_cases: list[tc.TestCase
             module_aliases, common_modules
         )
         functions = AbstractTestExporter._create_functions(asts, False)
-        module = ast.Module(body=import_nodes + functions)
+        module = ast.Module(body=import_nodes + functions, type_ignores=[])
         AbstractTestExporter._save_ast_to_file(path, module)

pynguin/testcase/execution.py

@@ -21,7 +21,6 @@
 from types import CodeType, ModuleType
 from typing import TYPE_CHECKING, Any, Callable
 
-import astor
 from bytecode import Compare
 from jellyfish import levenshtein_distance
 from ordered_set import OrderedSet
@@ -1114,13 +1113,13 @@ def _execute_statement(
     ) -> Exception | None:
         ast_node = exec_ctx.executable_node_for(statement)
         if self._logger.isEnabledFor(logging.DEBUG):
-            self._logger.debug("Executing %s", astor.to_source(ast_node))
+            self._logger.debug("Executing %s", ast.unparse(ast_node))
         code = compile(ast_node, "<ast>", "exec")
         try:
             # pylint: disable=exec-used
             exec(code, exec_ctx.global_namespace, exec_ctx.local_namespace)  # nosec
         except Exception as err:  # pylint: disable=broad-except
-            failed_stmt = astor.to_source(ast_node)
+            failed_stmt = ast.unparse(ast_node)
             TestCaseExecutor._logger.debug(
                 "Failed to execute statement:\n%s%s", failed_stmt, err.args
             )

pyproject.toml

@@ -38,7 +38,6 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.10"
-astor = "^0.8.1"
 simple-parsing = "^0.0.18"
 bytecode = "^0"
 typing_inspect = "^0"

tests/analyses/test_ast_to_statement.py

@@ -21,8 +21,7 @@
     [
         (
             """    float_0 = 1.1
-    var_0 = module_0.positional_only(float_0)
-"""
+    var_0 = module_0.positional_only(float_0)"""
         ),
         (
             """    float_0 = 1.1
@@ -32,8 +31,7 @@
     str_1 = 'key'
     str_2 = 'value'
     str_3 = {str_1: str_2}
-    var_1 = module_0.all_params(float_0, int_0, *var_0, param4=str_0, **str_3)
-"""
+    var_1 = module_0.all_params(float_0, int_0, *var_0, param4=str_0, **str_3)"""
         ),
     ],
 )
@@ -42,7 +40,6 @@ def test_parameter_mapping_roundtrip(testcase_seed, tmp_path):
         """# Automatically generated by Pynguin.
 import tests.fixtures.grammar.parameters as module_0
 
-
 def test_case_0():
 """
         + testcase_seed

tests/assertion/test_assertion_generation_integration.py

@@ -7,7 +7,6 @@
 import ast
 import importlib
 
-import astor
 import pytest
 
 import pynguin.assertion.assertiongenerator as ag
@@ -32,17 +31,15 @@
 assert human_0 is not None
 assert module_0.static_state == 0
 str_1 = human_0.get_name()
-assert str_1 == 'foo bar'
-""",
+assert str_1 == 'foo bar'""",
         ),
         (
             ag.MutationAnalysisAssertionGenerator,
             """str_0 = 'foo bar'
 float_0 = 39.82
 human_0 = module_0.Human(str_0, float_0)
 assert module_0.static_state == 0
-str_1 = human_0.get_name()
-""",
+str_1 = human_0.get_name()""",
         ),
     ],
 )
@@ -79,5 +76,9 @@ def test_generate_mutation_assertions(generator, expected_result):
 
         visitor = tc_to_ast.TestCaseToAstVisitor()
         test_case.accept(visitor)
-        source = astor.to_source(ast.Module(body=visitor.test_case_asts[0]))
+        source = ast.unparse(
+            ast.fix_missing_locations(
+                ast.Module(body=visitor.test_case_asts[0], type_ignores=[])
+            )
+        )
         assert source == expected_result

tests/assertion/test_assertion_to_ast.py

@@ -4,11 +4,10 @@
 #
 #  SPDX-License-Identifier: LGPL-3.0-or-later
 #
+import ast
 import enum
-from _ast import Module
 from unittest.mock import MagicMock
 
-import astor
 import pytest
 
 import pynguin.assertion.assertion as ass
@@ -24,34 +23,39 @@ def assertion_to_ast() -> ata.AssertionToAstVisitor:
     return ata.AssertionToAstVisitor(scope, module_aliases, set())
 
 
+def __create_source_from_ast(module_body: list[ast.stmt]) -> str:
+    return ast.unparse(
+        ast.fix_missing_locations(ast.Module(body=module_body, type_ignores=[]))
+    )
+
+
 def test_none(assertion_to_ast):
     assertion = ass.NotNoneAssertion(source=vr.VariableReference(MagicMock(), None))
     assertion.accept(assertion_to_ast)
     assert (
-        astor.to_source(Module(body=assertion_to_ast.nodes))
-        == "assert var_0 is not None\n"
+        __create_source_from_ast(assertion_to_ast.nodes) == "assert var_0 is not None"
     )
 
 
 @pytest.mark.parametrize(
     "obj,output",
     [
-        (True, "assert var_0 is True\n"),
-        (False, "assert var_0 is False\n"),
-        ((True, False), "assert var_0 == (True, False)\n"),
-        ([3, 8], "assert var_0 == [3, 8]\n"),
-        ([[3, 8], {"foo"}], "assert var_0 == [[3, 8], {'foo'}]\n"),
+        (True, "assert var_0 is True"),
+        (False, "assert var_0 is False"),
+        ((True, False), "assert var_0 == (True, False)"),
+        ([3, 8], "assert var_0 == [3, 8]"),
+        ([[3, 8], {"foo"}], "assert var_0 == [[3, 8], {'foo'}]"),
         (
             {"foo": ["nope", 1, False, None]},
-            "assert var_0 == {'foo': ['nope', 1, False, None]}\n",
+            "assert var_0 == {'foo': ['nope', 1, False, None]}",
         ),
         (
             {"foo": "bar", "baz": "argh"},
-            "assert var_0 == {'foo': 'bar', 'baz': 'argh'}\n",
+            "assert var_0 == {'foo': 'bar', 'baz': 'argh'}",
         ),
         (
             {enum.Enum("Dummy", "a").a: False},
-            "assert var_0 == {module_0.Dummy.a: False}\n",
+            "assert var_0 == {module_0.Dummy.a: False}",
         ),
     ],
 )
@@ -60,7 +64,7 @@ def test_object_assertion(assertion_to_ast, obj, output):
         source=vr.VariableReference(MagicMock(), None), value=obj
     )
     assertion.accept(assertion_to_ast)
-    assert astor.to_source(Module(body=assertion_to_ast.nodes)) == output
+    assert __create_source_from_ast(assertion_to_ast.nodes) == output
 
 
 def test_float_assertion(assertion_to_ast):
@@ -69,18 +73,18 @@ def test_float_assertion(assertion_to_ast):
     )
     assertion.accept(assertion_to_ast)
     assert (
-        astor.to_source(Module(body=assertion_to_ast.nodes))
-        == "assert var_0 == pytest.approx(1.5, abs=0.01, rel=0.01)\n"
+        __create_source_from_ast(assertion_to_ast.nodes)
+        == "assert var_0 == pytest.approx(1.5, abs=0.01, rel=0.01)"
     )
 
 
 @pytest.mark.parametrize(
     "length, output",
-    [(0, "assert len(var_0) == 0\n"), (42, "assert len(var_0) == 42\n")],
+    [(0, "assert len(var_0) == 0"), (42, "assert len(var_0) == 42")],
 )
 def test_collection_length(assertion_to_ast, length, output):
     assertion = ass.CollectionLengthAssertion(
         source=vr.VariableReference(MagicMock(), None), length=length
     )
     assertion.accept(assertion_to_ast)
-    assert astor.to_source(Module(body=assertion_to_ast.nodes)) == output
+    assert __create_source_from_ast(assertion_to_ast.nodes) == output

tests/generation/export/test_pytestexporter.py

@@ -17,7 +17,6 @@ def test_export_sequence(exportable_test_case, tmp_path):
 import pytest
 import tests.fixtures.accessibles.accessible as module_0
 
-
 def test_case_0():
     int_0 = 5
     some_type_0 = module_0.SomeType(int_0)
@@ -26,13 +25,11 @@ def test_case_0():
     float_1 = module_0.simple_function(float_0)
     assert float_1 == pytest.approx(42.23, abs=0.01, rel=0.01)
 
-
 def test_case_1():
     int_0 = 5
     some_type_0 = module_0.SomeType(int_0)
     assert some_type_0 == 5
     float_0 = 42.23
     float_1 = module_0.simple_function(float_0)
-    assert float_1 == pytest.approx(42.23, abs=0.01, rel=0.01)
-"""
+    assert float_1 == pytest.approx(42.23, abs=0.01, rel=0.01)"""
     )