[DEV-12543] Add rule for disallowing migration renames (#16)

* add rule for disallowing migration renames

* update pre-commit package versions + fix lint issue

* grr linter

* push version to 0.1.1

* up version to 0.1.2 for free release tag

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.0.1
+    rev: v4.4.0
     hooks:
       - id: check-json
       - id: check-yaml
@@ -12,32 +12,32 @@ repos:
       - id: requirements-txt-fixer
 
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.31.1
+    rev: v3.8.0
     hooks:
       - id: pyupgrade
         args: ['--py38-plus', '--keep-mock']
 
   - repo: https://github.com/timothycrosley/isort
-    rev: 5.10.1
+    rev: 5.12.0
     hooks:
       - id: isort
         additional_dependencies:
           - 'toml'
 
   - repo: https://github.com/PyCQA/pydocstyle
-    rev: 6.1.1
+    rev: 6.3.0
     hooks:
       - id: pydocstyle
         args: ['--add-ignore=D100,D101,D102,D103,D104,D105,D106,D107,D205,D400,D401']
 
   - repo: https://github.com/psf/black
-    rev: 22.3.0
+    rev: 23.3.0
     hooks:
       - id: black
         language_version: python3.8
 
 
   - repo: https://github.com/pycqa/flake8
-    rev: 4.0.1
+    rev: 6.0.0
     hooks:
       - id: flake8

flake8_routable.py

@@ -32,6 +32,7 @@
 ROU106 = "ROU106 Relative imports are not allowed"
 ROU107 = "ROU107 Inline function import is not at top of statement"
 ROU108 = "ROU108 Import from model module instead of sub-packages"
+ROU109 = "ROU109 Disallow rename migrations"
 
 
 @dataclass
@@ -176,6 +177,7 @@ def visit(self, file_tokens: List[tokenize.TokenInfo]) -> None:
         self.lines_with_blank_lines_after_comments()
         self.lines_with_invalid_docstrings()
         self.lines_with_invalid_multi_line_strings()
+        self.rename_migrations()
 
     def lines_with_blank_lines_after_comments(self) -> None:
         """
@@ -295,7 +297,7 @@ def lines_with_invalid_docstrings(self) -> None:
         # last line number of the last statement (in case it spans multiple lines)
         last_stmt_line_no = None
 
-        for (token_type, token_str, start_indices, end_indices, line) in self._file_tokens:
+        for token_type, token_str, start_indices, end_indices, line in self._file_tokens:
             line_no = start_indices[0]
 
             if token_type in (tokenize.DEDENT, tokenize.INDENT, tokenize.NEWLINE, tokenize.NL):
@@ -330,6 +332,20 @@ def lines_with_invalid_docstrings(self) -> None:
             # grouped tokens will no longer be a comment's prefix if they aren't new lines or indents (earlier clause)
             is_whitespace_prefix = False
 
+    def rename_migrations(self) -> None:
+        """Migrations should not allow renames."""
+        reported = set()
+        disallowed_migration_text = "migrations.RenameField"
+
+        for line_token in self._file_tokens:
+            if line_token.start[0] in reported:
+                # There could be many tokens on a same line.
+                continue
+
+            if disallowed_migration_text in line_token.line:
+                reported.add(line_token.start[0])
+                self.errors.append((*line_token.start, ROU109))
+
 
 class Plugin:
     """Flake8 plugin for Routable's best coding practices."""

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = flake8_routable
-version = 0.1.0
+version = 0.1.2
 
 [options]
 py_modules = flake8_routable

tests/test_flake8_routable.py

@@ -506,6 +506,36 @@ def test_model_module_import(self):
         assert error == set()
 
 
+class TestROU109:
+    ADD_MIGRATION = """class Migration(migrations.Migration):
+        dependencies = []
+        operations = [
+            migrations.AddField(
+                model_name="model_one",
+                name="swift_charge_option",
+                field=models.TextField(blank=True, null=True),
+            )
+        ]"""
+
+    RENAME_MIGRATION = """class Migration(migrations.Migration):
+        dependencies = []
+        operations = [
+            migrations.RenameField(
+                model_name="model_one",
+                old="field_one",
+                new="field_two",
+            )
+        ]"""
+
+    def test_correct_no_import_from_tests(self):
+        errors = results(self.ADD_MIGRATION)
+        assert errors == set()
+
+    def test_incorrect_import_from_tests(self):
+        errors = results(self.RENAME_MIGRATION)
+        assert errors == {"4:12: ROU109 Disallow rename migrations"}
+
+
 class TestVisitor:
     def test_parse_to_string_warning(self):
         visitor = Visitor()