New codemod to remove global lines at module level

integration_tests/test_remove_module_global.py

@@ -0,0 +1,19 @@
+from core_codemods.remove_module_global import RemoveModuleGlobal
+from integration_tests.base_test import (
+    BaseIntegrationTest,
+    original_and_expected_from_code_path,
+)
+
+
+class TestRemoveModuleGlobal(BaseIntegrationTest):
+    codemod = RemoveModuleGlobal
+    code_path = "tests/samples/module_global.py"
+    original_code, _ = original_and_expected_from_code_path(code_path, [])
+    expected_new_code = """
+price = 25
+print("hello")
+price = 30
+""".lstrip()
+    expected_diff = '--- \n+++ \n@@ -1,4 +1,3 @@\n price = 25\n print("hello")\n-global price\n price = 30\n'
+    expected_line_change = "3"
+    change_description = RemoveModuleGlobal.CHANGE_DESCRIPTION

src/codemodder/scripts/generate_docs.py

@@ -186,6 +186,10 @@ class DocMetadata:
         importance="Low",
         guidance_explained="We believe this change is safe and will not cause any issues.",
     ),
+    "remove-module-global": DocMetadata(
+        importance="Low",
+        guidance_explained="Since the `global` keyword is intended for use in non-module scopes, using it at the module scope is unnecessary.",
+    ),
 }
 
 

src/core_codemods/__init__.py

@@ -40,6 +40,7 @@
 from .exception_without_raise import ExceptionWithoutRaise
 from .literal_or_new_object_identity import LiteralOrNewObjectIdentity
 from .subprocess_shell_false import SubprocessShellFalse
+from .remove_module_global import RemoveModuleGlobal
 
 registry = CodemodCollection(
     origin="pixee",
@@ -86,5 +87,6 @@
         FlaskJsonResponseType,
         ExceptionWithoutRaise,
         LiteralOrNewObjectIdentity,
+        RemoveModuleGlobal,
     ],
 )

src/core_codemods/docs/pixee_python_remove-module-global.md

@@ -0,0 +1,10 @@
+Using the `global` keyword is necessary only when you intend to modify a module-level (aka global) variable within a non-global scope, such as within a class or function. It is unnecessary to call `global` at the module-level.
+
+Our changes look something like this:
+
+```diff
+ price = 25
+ print("hello")
+- global price
+ price = 30
+```

src/core_codemods/remove_module_global.py

@@ -0,0 +1,26 @@
+import libcst as cst
+from libcst.metadata import GlobalScope, ScopeProvider
+from typing import Union
+from codemodder.codemods.api import BaseCodemod, ReviewGuidance
+from codemodder.codemods.utils_mixin import NameResolutionMixin
+
+
+class RemoveModuleGlobal(BaseCodemod, NameResolutionMixin):
+    NAME = "remove-module-global"
+    SUMMARY = "Remove `global` Usage at Module Level"
+    REVIEW_GUIDANCE = ReviewGuidance.MERGE_WITHOUT_REVIEW
+    DESCRIPTION = "Remove `global` usage at module level."
+    REFERENCES: list = []
+
+    def leave_Global(
+        self, original_node: cst.Global, _
+    ) -> Union[cst.Global, cst.RemovalSentinel,]:
+        if not self.filter_by_path_includes_or_excludes(
+            self.node_position(original_node)
+        ):
+            return original_node
+        scope = self.get_metadata(ScopeProvider, original_node)
+        if isinstance(scope, GlobalScope):
+            self.report_change(original_node)
+            return cst.RemovalSentinel.REMOVE
+        return original_node

tests/codemods/test_remove_module_global.py

@@ -0,0 +1,63 @@
+from textwrap import dedent
+from core_codemods.remove_module_global import RemoveModuleGlobal
+from tests.codemods.base_codemod_test import BaseCodemodTest
+
+
+class TestJwtDecodeVerify(BaseCodemodTest):
+    codemod = RemoveModuleGlobal
+
+    def test_name(self):
+        assert self.codemod.name() == "remove-module-global"
+
+    def test_simple(self, tmpdir):
+        input_code = """\
+        price = 25
+        global price
+        """
+        expected = """\
+        price = 25
+        """
+        self.run_and_assert(tmpdir, dedent(input_code), dedent(expected))
+        assert len(self.file_context.codemod_changes) == 1
+
+    def test_reassigned(self, tmpdir):
+        input_code = """\
+        price = 25
+        print("hello")
+        global price
+        price = 30
+        """
+        expected = """\
+        price = 25
+        print("hello")
+        price = 30
+        """
+        self.run_and_assert(tmpdir, dedent(input_code), dedent(expected))
+        assert len(self.file_context.codemod_changes) == 1
+
+    def test_attr_call(self, tmpdir):
+        input_code = """\
+        class Price:
+            pass
+        PRICE = Price()
+        global PRICE
+        PRICE.__repr__
+        """
+        expected = """\
+        class Price:
+            pass
+        PRICE = Price()
+        PRICE.__repr__
+        """
+        self.run_and_assert(tmpdir, dedent(input_code), dedent(expected))
+        assert len(self.file_context.codemod_changes) == 1
+
+    def test_correct_scope(self, tmpdir):
+        input_code = """\
+        price = 25
+        def change_price():
+            global price
+            price = 30
+        """
+        self.run_and_assert(tmpdir, dedent(input_code), dedent(input_code))
+        assert len(self.file_context.codemod_changes) == 0

tests/samples/module_global.py

@@ -0,0 +1,4 @@
+price = 25
+print("hello")
+global price
+price = 30