attempt to add flake8 and isort

.travis.yml

@@ -4,10 +4,6 @@ dist: xenial
 sudo: required
 jobs:
   include:
-    - name: Typecheck Django test suite
-      python: 3.7
-      script: 'python ./scripts/typecheck_tests.py'
-
     - name: Run plugin test suite with python 3.7
       python: 3.7
       script: |
@@ -20,10 +16,22 @@ jobs:
         set -e
         pytest
 
+    - name: Typecheck Django test suite
+      python: 3.7
+      script: 'python ./scripts/typecheck_tests.py'
+
     - name: Lint with black
       python: 3.7
       script: 'black --check --line-length=120 django-stubs/'
 
+    - name: Lint plugin code with flake8
+      python: 3.7
+      script: 'flake8'
+
+    - name: Lint plugin code with isort
+      python: 3.7
+      script: 'isort --check'
+
 before_install: |
   # Upgrade pip, setuptools, and wheel
   pip install -U pip setuptools wheel

dev-requirements.txt

@@ -1,3 +1,5 @@
 black
 pytest-mypy-plugins
+flake8
+isort==4.3.4
 -e .

mypy_django_plugin/config.py

@@ -1,5 +1,5 @@
 from configparser import ConfigParser
-from typing import List, Optional
+from typing import Optional
 
 from dataclasses import dataclass
 
@@ -16,10 +16,12 @@ class Config:
         if not ini_config.has_section('mypy_django_plugin'):
             raise ValueError('Invalid config file: no [mypy_django_plugin] section')
 
-        django_settings = ini_config.get('mypy_django_plugin', 'django_settings',
-                                         fallback=None)
-        if django_settings:
+        django_settings = ini_config.get('mypy_django_plugin', 'django_settings')
+        if type(django_settings) == object:
+            django_settings = None
+        else:
             django_settings = django_settings.strip()
+
         return Config(django_settings_module=django_settings,
-                      ignore_missing_settings=ini_config.get('mypy_django_plugin', 'ignore_missing_settings',
-                                                             fallback=False))
+                      ignore_missing_settings=bool(ini_config.get('mypy_django_plugin', 'ignore_missing_settings',
+                                                                  fallback=False)))

mypy_django_plugin/helpers.py

@@ -2,10 +2,13 @@ import typing
 from typing import Dict, Optional
 
 from mypy.checker import TypeChecker
-from mypy.nodes import AssignmentStmt, ClassDef, Expression, ImportedName, Lvalue, MypyFile, NameExpr, SymbolNode, \
-    TypeInfo
+from mypy.nodes import (
+    AssignmentStmt, ClassDef, Expression, ImportedName, Lvalue, MypyFile, NameExpr, SymbolNode, TypeInfo,
+)
 from mypy.plugin import FunctionContext, MethodContext
-from mypy.types import AnyType, Instance, NoneTyp, Type, TypeOfAny, TypeVarType, UnionType
+from mypy.types import (
+    AnyType, Instance, NoneTyp, Type, TypeOfAny, TypeVarType, UnionType,
+)
 
 MODEL_CLASS_FULLNAME = 'django.db.models.base.Model'
 FIELD_FULLNAME = 'django.db.models.fields.Field'

mypy_django_plugin/main.py

@@ -2,19 +2,28 @@ import os
 from typing import Callable, Dict, Optional, Union, cast
 
 from mypy.checker import TypeChecker
-from mypy.nodes import MemberExpr, TypeInfo, NameExpr
+from mypy.nodes import MemberExpr, NameExpr, TypeInfo
 from mypy.options import Options
-from mypy.plugin import AttributeContext, ClassDefContext, FunctionContext, MethodContext, Plugin
-from mypy.types import AnyType, Instance, Type, TypeOfAny, TypeType, UnionType, CallableType, NoneTyp
+from mypy.plugin import (
+    AttributeContext, ClassDefContext, FunctionContext, MethodContext, Plugin,
+)
+from mypy.types import (
+    AnyType, CallableType, Instance, NoneTyp, Type, TypeOfAny, TypeType, UnionType,
+)
 
 from mypy_django_plugin import helpers, monkeypatch
 from mypy_django_plugin.config import Config
 from mypy_django_plugin.transformers import fields, init_create
-from mypy_django_plugin.transformers.forms import make_meta_nested_class_inherit_from_any
-from mypy_django_plugin.transformers.migrations import determine_model_cls_from_string_for_migrations, \
-    get_string_value_from_expr
+from mypy_django_plugin.transformers.forms import (
+    make_meta_nested_class_inherit_from_any,
+)
+from mypy_django_plugin.transformers.migrations import (
+    determine_model_cls_from_string_for_migrations, get_string_value_from_expr,
+)
 from mypy_django_plugin.transformers.models import process_model_class
-from mypy_django_plugin.transformers.settings import AddSettingValuesToDjangoConfObject, get_settings_metadata
+from mypy_django_plugin.transformers.settings import (
+    AddSettingValuesToDjangoConfObject, get_settings_metadata,
+)
 
 
 def transform_model_class(ctx: ClassDefContext) -> None:

mypy_django_plugin/monkeypatch/__init__.py

@@ -1,4 +0,0 @@
-from .dependencies import (add_modules_as_a_source_seed_files,
-                           inject_modules_as_dependencies_for_django_conf_settings,
-                           restore_original_load_graph,
-                           restore_original_dependencies_handling)

mypy_django_plugin/transformers/fields.py

@@ -3,9 +3,11 @@ from typing import Optional, cast
 from mypy.checker import TypeChecker
 from mypy.nodes import ListExpr, NameExpr, StrExpr, TupleExpr, TypeInfo, Var
 from mypy.plugin import FunctionContext
-from mypy.types import AnyType, CallableType, Instance, TupleType, Type, TypeOfAny, UnionType
+from mypy.types import (
+    AnyType, CallableType, Instance, TupleType, Type, TypeOfAny, UnionType,
+)
+
 from mypy_django_plugin import helpers
-from mypy_django_plugin.transformers.models import iter_over_assignments
 
 
 def extract_referred_to_type(ctx: FunctionContext) -> Optional[Instance]:
@@ -154,7 +156,7 @@ def record_field_properties_into_outer_model_class(ctx: FunctionContext) -> None
         return
 
     field_name = None
-    for name_expr, stmt in iter_over_assignments(outer_model.defn):
+    for name_expr, stmt in helpers.iter_over_assignments(outer_model.defn):
         if stmt == ctx.context and isinstance(name_expr, NameExpr):
             field_name = name_expr.name
             break

mypy_django_plugin/transformers/forms.py

@@ -1,4 +1,5 @@
 from mypy.plugin import ClassDefContext
+
 from mypy_django_plugin import helpers
 
 

mypy_django_plugin/transformers/init_create.py

@@ -4,8 +4,8 @@ from mypy.checker import TypeChecker
 from mypy.nodes import TypeInfo, Var
 from mypy.plugin import FunctionContext, MethodContext
 from mypy.types import AnyType, Instance, Type, TypeOfAny
+
 from mypy_django_plugin import helpers
-from mypy_django_plugin.helpers import extract_field_setter_type, extract_explicit_set_type_of_model_primary_key, get_fields_metadata
 from mypy_django_plugin.transformers.fields import get_private_descriptor_type
 
 
@@ -106,7 +106,7 @@ def redefine_and_typecheck_model_create(ctx: MethodContext) -> Type:
 
 
 def extract_choices_type(model: TypeInfo, field_name: str) -> Optional[str]:
-    field_metadata = get_fields_metadata(model).get(field_name, {})
+    field_metadata = helpers.get_fields_metadata(model).get(field_name, {})
     if 'choices' in field_metadata:
         return field_metadata['choices']
     return None
@@ -117,7 +117,7 @@ def extract_expected_types(ctx: FunctionContext, model: TypeInfo,
     api = cast(TypeChecker, ctx.api)
 
     expected_types: Dict[str, Type] = {}
-    primary_key_type = extract_explicit_set_type_of_model_primary_key(model)
+    primary_key_type = helpers.extract_explicit_set_type_of_model_primary_key(model)
     if not primary_key_type:
         # no explicit primary key, set pk to Any and add id
         primary_key_type = AnyType(TypeOfAny.special_form)
@@ -143,7 +143,7 @@ def extract_expected_types(ctx: FunctionContext, model: TypeInfo,
                     expected_types[name + '_id'] = AnyType(TypeOfAny.from_unimported_type)
 
                 elif isinstance(typ, Instance):
-                    field_type = extract_field_setter_type(typ)
+                    field_type = helpers.extract_field_setter_type(typ)
                     if field_type is None:
                         continue
 
@@ -156,8 +156,9 @@ def extract_expected_types(ctx: FunctionContext, model: TypeInfo,
                         if is_nullable:
                             referred_to_model = helpers.make_required(typ.args[1])
 
-                        if isinstance(referred_to_model, Instance) and referred_to_model.type.has_base(helpers.MODEL_CLASS_FULLNAME):
-                            pk_type = extract_explicit_set_type_of_model_primary_key(referred_to_model.type)
+                        if isinstance(referred_to_model, Instance) and referred_to_model.type.has_base(
+                                helpers.MODEL_CLASS_FULLNAME):
+                            pk_type = helpers.extract_explicit_set_type_of_model_primary_key(referred_to_model.type)
                             if not pk_type:
                                 # extract set type of AutoField
                                 autofield_info = api.lookup_typeinfo('django.db.models.fields.AutoField')
@@ -170,7 +171,7 @@ def extract_expected_types(ctx: FunctionContext, model: TypeInfo,
 
                         expected_types[name + '_id'] = related_primary_key_type
 
-                    field_metadata = get_fields_metadata(model).get(name, {})
+                    field_metadata = helpers.get_fields_metadata(model).get(name, {})
                     if field_type:
                         # related fields could be None in __init__ (but should be specified before save())
                         if helpers.has_any_of_bases(typ.type, (helpers.FOREIGN_KEY_FULLNAME,
@@ -178,7 +179,8 @@ def extract_expected_types(ctx: FunctionContext, model: TypeInfo,
                             field_type = helpers.make_optional(field_type)
 
                         # if primary_key=True and default specified
-                        elif field_metadata.get('primary_key', False) and field_metadata.get('default_specified', False):
+                        elif field_metadata.get('primary_key', False) and field_metadata.get('default_specified',
+                                                                                             False):
                             field_type = helpers.make_optional(field_type)
 
                         expected_types[name] = field_type

mypy_django_plugin/transformers/migrations.py

@@ -4,6 +4,7 @@ from mypy.checker import TypeChecker
 from mypy.nodes import Expression, StrExpr, TypeInfo
 from mypy.plugin import MethodContext
 from mypy.types import Instance, Type, TypeType
+
 from mypy_django_plugin import helpers
 
 

mypy_django_plugin/transformers/models.py

@@ -2,14 +2,16 @@ from abc import ABCMeta, abstractmethod
 from typing import Dict, Iterator, List, Optional, Tuple, cast
 
 import dataclasses
-from mypy.nodes import ARG_STAR, ARG_STAR2, Argument, CallExpr, ClassDef, Expression, IndexExpr, \
-    Lvalue, MDEF, MemberExpr, MypyFile, NameExpr, StrExpr, SymbolTableNode, TypeInfo, Var
+from mypy.nodes import (
+    ARG_STAR, ARG_STAR2, MDEF, Argument, CallExpr, ClassDef, Expression, IndexExpr, Lvalue, MemberExpr, MypyFile,
+    NameExpr, StrExpr, SymbolTableNode, TypeInfo, Var,
+)
 from mypy.plugin import ClassDefContext
 from mypy.plugins.common import add_method
 from mypy.semanal import SemanticAnalyzerPass2
 from mypy.types import AnyType, Instance, NoneTyp, TypeOfAny
+
 from mypy_django_plugin import helpers
-from mypy_django_plugin.helpers import iter_over_assignments
 
 
 @dataclasses.dataclass
@@ -48,7 +50,7 @@ class ModelClassInitializer(metaclass=ABCMeta):
 
 
 def iter_call_assignments(klass: ClassDef) -> Iterator[Tuple[Lvalue, CallExpr]]:
-    for lvalue, rvalue in iter_over_assignments(klass):
+    for lvalue, rvalue in helpers.iter_over_assignments(klass):
         if isinstance(rvalue, CallExpr):
             yield lvalue, rvalue
 

mypy_django_plugin/transformers/settings.py

@@ -1,6 +1,8 @@
 from typing import Iterable, List, Optional, cast
 
-from mypy.nodes import ClassDef, Context, ImportAll, MypyFile, SymbolNode, SymbolTableNode, TypeInfo, Var
+from mypy.nodes import (
+    ClassDef, Context, ImportAll, MypyFile, SymbolNode, SymbolTableNode, TypeInfo, Var,
+)
 from mypy.plugin import ClassDefContext
 from mypy.semanal import SemanticAnalyzerPass2
 from mypy.types import AnyType, Instance, NoneTyp, Type, TypeOfAny, UnionType
@@ -56,7 +58,7 @@ def load_settings_from_names(settings_classdef: ClassDef,
                     settings_classdef.info.names[name] = copied
                 else:
                     var = Var(name, AnyType(TypeOfAny.unannotated))
-                    var.info = api.named_type('__builtins__.object').type
+                    var.info = api.named_type('__builtins__.object').type  # outer class type
                     settings_classdef.info.names[name] = SymbolTableNode(sym.kind, var)
 
                 settings_metadata[name] = module.fullname()
@@ -67,11 +69,12 @@ def get_import_star_modules(api: SemanticAnalyzerPass2, module: MypyFile) -> Lis
     for module_import in module.imports:
         # relative import * are not resolved by mypy
         if isinstance(module_import, ImportAll) and module_import.relative:
-            absolute_import_path, correct = correct_relative_import(module.fullname(), module_import.relative, module_import.id,
-                                                                    is_cur_package_init_file=False)
+            absolute_import_path, correct = correct_relative_import(module.fullname(), module_import.relative,
+                                                                    module_import.id, is_cur_package_init_file=False)
             if not correct:
                 return []
-            for path in [absolute_import_path] + get_import_star_modules(api, module=api.modules.get(absolute_import_path)):
+            for path in [absolute_import_path] + get_import_star_modules(api,
+                                                                         module=api.modules.get(absolute_import_path)):
                 if path not in import_star_modules:
                     import_star_modules.append(path)
     return import_star_modules

pytest.ini

@@ -1,5 +1,4 @@
 [pytest]
-
 testpaths = ./test-data
 addopts =
     --tb=native

scripts/typecheck_tests.py

@@ -37,7 +37,8 @@ IGNORED_ERRORS = {
         # settings
         re.compile(r'Module has no attribute "[A-Z_]+"'),
         # attributes assigned to test functions
-        re.compile(r'"Callable\[(\[(Any(, )?)*((, )?VarArg\(Any\))?((, )?KwArg\(Any\))?\]|\.\.\.), Any\]" has no attribute'),
+        re.compile(
+            r'"Callable\[(\[(Any(, )?)*((, )?VarArg\(Any\))?((, )?KwArg\(Any\))?\]|\.\.\.), Any\]" has no attribute'),
         # assign empty tuple
         re.compile(r'Incompatible types in assignment \(expression has type "Tuple\[\]", '
                    r'variable has type "Tuple\[[A-Za-z, ]+\]"'),
@@ -54,8 +55,9 @@ IGNORED_ERRORS = {
         'ValuesIterable',
         'Value of type "Optional[Dict[str, Any]]" is not indexable',
         'Argument 1 to "len" has incompatible type "Optional[List[_Record]]"; expected "Sized"',
-        'Argument 1 to "loads" has incompatible type "Union[bytes, str, None]"; expected "Union[str, bytes, bytearray]"',
-        'Incompatible types in assignment (expression has type "None", variable has type Module)'
+        'Argument 1 to "loads" has incompatible type "Union[bytes, str, None]"; '
+        + 'expected "Union[str, bytes, bytearray]"',
+        'Incompatible types in assignment (expression has type "None", variable has type Module)',
     ],
     'admin_changelist': [
         'Incompatible types in assignment (expression has type "FilteredChildAdmin", variable has type "ChildAdmin")'
@@ -65,8 +67,9 @@ IGNORED_ERRORS = {
     ],
     'admin_widgets': [
         'Incompatible types in assignment (expression has type "RelatedFieldWidgetWrapper", '
-        'variable has type "AdminRadioSelect")',
-        'Incompatible types in assignment (expression has type "Union[Widget, Any]", variable has type "AutocompleteSelect")'
+        + 'variable has type "AdminRadioSelect")',
+        'Incompatible types in assignment (expression has type "Union[Widget, Any]", '
+        + 'variable has type "AutocompleteSelect")'
     ],
     'admin_utils': [
         re.compile(r'Argument [0-9] to "lookup_field" has incompatible type'),
@@ -91,11 +94,13 @@ IGNORED_ERRORS = {
         'Incompatible types in assignment (expression has type "FlatValuesListIterable", '
         + 'variable has type "ValuesListIterable")',
         'Incompatible type for "contact" of "Book" (got "Optional[Author]", expected "Union[Author, Combinable]")',
-        'Incompatible type for "publisher" of "Book" (got "Optional[Publisher]", expected "Union[Publisher, Combinable]")'
+        'Incompatible type for "publisher" of "Book" (got "Optional[Publisher]", '
+        + 'expected "Union[Publisher, Combinable]")'
     ],
     'aggregation_regress': [
         'Incompatible types in assignment (expression has type "List[str]", variable has type "QuerySet[Author]")',
-        'Incompatible types in assignment (expression has type "FlatValuesListIterable", variable has type "QuerySet[Any]")',
+        'Incompatible types in assignment (expression has type "FlatValuesListIterable", '
+        + 'variable has type "QuerySet[Any]")',
         'Too few arguments for "count" of "Sequence"'
     ],
     'apps': [
@@ -176,8 +181,8 @@ IGNORED_ERRORS = {
         'variable has type "SongForm"',
         '"full_clean" of "BaseForm" does not return a value',
         'No overload variant of "zip" matches argument types "Tuple[str, str, str]", "object"',
-        'note:',
-        'Incompatible types in assignment (expression has type "GetDateShowHiddenInitial", variable has type "GetDate")',
+        'Incompatible types in assignment (expression has type "GetDateShowHiddenInitial", '
+        + 'variable has type "GetDate")',
         re.compile(r'Incompatible types in assignment \(expression has type "[a-zA-Z]+Field", '
                    r'base class "BaseForm" defined the type as "Dict\[str, Any\]"\)'),
         'List or tuple expected as variable arguments',
@@ -216,13 +221,13 @@ IGNORED_ERRORS = {
     ],
     'lookup': [
         'Unexpected keyword argument "headline__startswith" for "in_bulk" of "QuerySet"',
-        'note: '
     ],
     'many_to_one': [
         'Incompatible type for "parent" of "Child" (got "None", expected "Union[Parent, Combinable]")'
     ],
     'model_inheritance_regress': [
-        'Incompatible types in assignment (expression has type "List[Supplier]", variable has type "QuerySet[Supplier]")'
+        'Incompatible types in assignment (expression has type "List[Supplier]", '
+        + 'variable has type "QuerySet[Supplier]")'
     ],
     'model_meta': [
         '"object" has no attribute "items"',
@@ -238,10 +243,10 @@ IGNORED_ERRORS = {
         'Cannot assign multiple types to name "PersonTwoImages" without an explicit "Type[...]" annotation',
         'Incompatible types in assignment (expression has type "Type[Person]", '
         + 'base class "ImageFieldTestMixin" defined the type as "Type[PersonWithHeightAndWidth]")',
-        'note: "Person" defined here'
     ],
     'model_formsets': [
-        'Incompatible types in string interpolation (expression has type "object", placeholder has type "Union[int, float]")'
+        'Incompatible types in string interpolation (expression has type "object", '
+        + 'placeholder has type "Union[int, float]")'
     ],
     'model_formsets_regress': [
         'Incompatible types in assignment (expression has type "Model", variable has type "User")'
@@ -287,9 +292,11 @@ IGNORED_ERRORS = {
         'Incompatible types in assignment (expression has type "Type[Field[Any, Any]]',
         'DummyArrayField',
         'DummyJSONField',
-        'Argument "encoder" to "JSONField" has incompatible type "DjangoJSONEncoder"; expected "Optional[Type[JSONEncoder]]"',
+        'Argument "encoder" to "JSONField" has incompatible type "DjangoJSONEncoder"; '
+        + 'expected "Optional[Type[JSONEncoder]]"',
         'for model "CITestModel"',
-        'Incompatible type for "field" of "IntegerArrayModel" (got "None", expected "Union[Sequence[int], Combinable]")'
+        'Incompatible type for "field" of "IntegerArrayModel" (got "None", '
+        + 'expected "Union[Sequence[int], Combinable]")'
     ],
     'properties': [
         re.compile('Unexpected attribute "(full_name|full_name_2)" for model "Person"')
@@ -334,11 +341,14 @@ IGNORED_ERRORS = {
         'Incompatible types in assignment (expression has type "Thread", variable has type "Callable[[], Any]")'
     ],
     'test_client': [
-        'Incompatible types in assignment (expression has type "StreamingHttpResponse", variable has type "HttpResponse")',
-        'Incompatible types in assignment (expression has type "HttpResponse", variable has type "StreamingHttpResponse")'
+        'Incompatible types in assignment (expression has type "StreamingHttpResponse", '
+        + 'variable has type "HttpResponse")',
+        'Incompatible types in assignment (expression has type "HttpResponse", '
+        + 'variable has type "StreamingHttpResponse")'
     ],
     'test_client_regress': [
-        'Incompatible types in assignment (expression has type "Dict[<nothing>, <nothing>]", variable has type "SessionBase")',
+        'Incompatible types in assignment (expression has type "Dict[<nothing>, <nothing>]", '
+        + 'variable has type "SessionBase")',
         'Unsupported left operand type for + ("None")',
         'Both left and right operands are unions'
     ],
@@ -348,7 +358,8 @@ IGNORED_ERRORS = {
     'test_runner': [
         'Value of type "TestSuite" is not indexable',
         '"TestSuite" has no attribute "_tests"',
-        'Argument "result" to "run" of "TestCase" has incompatible type "RemoteTestResult"; expected "Optional[TestResult]"',
+        'Argument "result" to "run" of "TestCase" has incompatible type "RemoteTestResult"; '
+        + 'expected "Optional[TestResult]"',
         'Item "TestSuite" of "Union[TestCase, TestSuite]" has no attribute "id"',
         'MockTestRunner',
         'Incompatible types in assignment (expression has type "Tuple[Union[TestCase, TestSuite], ...]", '

setup.cfg

@@ -0,0 +1,29 @@
+[isort]
+skip =
+    django-sources,
+    django-stubs,
+    test-data
+include_trailing_comma = true
+multi_line_output = 5
+wrap_length = 120
+
+[flake8]
+exclude =
+    django-sources,
+    django-stubs,
+    test-data
+max_line_length = 120
+
+[tool:pytest]
+testpaths = ./test-data
+addopts =
+    --tb=native
+    --mypy-ini-file=./test-data/plugins.ini
+    -s
+    -v
+
+[bdist_wheel]
+universal = 1
+
+[metadata]
+license_file = LICENSE.txt