Implemented #1751: Strict typing enforcement (turned on mypy strict m…

…ode).

CHANGELOG.md

@@ -18,6 +18,7 @@ Find out more about isort's release policy [here](https://pycqa.github.io/isort/
 
 #### Goal Zero (Tickets related to aspirational goal of achieving 0 regressions for remaining 5.0.0 lifespan):
   - Implemented #1394: 100% branch coverage (in addition to line coverage) enforced.
+  - Implemented #1751: Strict typing enforcement (turned on mypy strict mode).
 
 ### 5.8.0 March 20th 2021
   - Fixed #1631: as import comments can in some cases be duplicated.

isort/__init__.py

@@ -1,4 +1,23 @@
 """Defines the public isort interface"""
+__all__ = (
+    "Config",
+    "ImportKey",
+    "__version__",
+    "check_code",
+    "check_file",
+    "check_stream",
+    "code",
+    "file",
+    "find_imports_in_code",
+    "find_imports_in_file",
+    "find_imports_in_paths",
+    "find_imports_in_stream",
+    "place_module",
+    "place_module_with_reason",
+    "settings",
+    "stream",
+)
+
 from . import settings
 from ._version import __version__
 from .api import ImportKey

isort/_future/__init__.py

@@ -1,7 +1,7 @@
 import sys
 
 if sys.version_info.major <= 3 and sys.version_info.minor <= 6:
-    from . import _dataclasses as dataclasses  # type: ignore
+    from . import _dataclasses as dataclasses
 
 else:
     import dataclasses  # type: ignore

isort/api.py

@@ -1,11 +1,27 @@
+__all__ = (
+    "ImportKey",
+    "check_code_string",
+    "check_file",
+    "check_stream",
+    "find_imports_in_code",
+    "find_imports_in_file",
+    "find_imports_in_paths",
+    "find_imports_in_stream",
+    "place_module",
+    "place_module_with_reason",
+    "sort_code_string",
+    "sort_file",
+    "sort_stream",
+)
+
 import contextlib
 import shutil
 import sys
 from enum import Enum
 from io import StringIO
 from itertools import chain
 from pathlib import Path
-from typing import Iterator, Optional, Set, TextIO, Union, cast
+from typing import Any, Iterator, Optional, Set, TextIO, Union, cast
 from warnings import warn
 
 from isort import core
@@ -57,8 +73,8 @@ def sort_code_string(
     file_path: Optional[Path] = None,
     disregard_skip: bool = False,
     show_diff: Union[bool, TextIO] = False,
-    **config_kwargs,
-):
+    **config_kwargs: Any,
+) -> str:
     """Sorts any imports within the provided code string, returning a new string with them sorted.
 
     - **code**: The string of code with imports that need to be sorted.
@@ -93,7 +109,7 @@ def check_code_string(
     config: Config = DEFAULT_CONFIG,
     file_path: Optional[Path] = None,
     disregard_skip: bool = False,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> bool:
     """Checks the order, format, and categorization of imports within the provided code string.
     Returns `True` if everything is correct, otherwise `False`.
@@ -127,7 +143,7 @@ def sort_stream(
     disregard_skip: bool = False,
     show_diff: Union[bool, TextIO] = False,
     raise_on_skip: bool = True,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> bool:
     """Sorts any imports within the provided code stream, outputs to the provided output stream.
      Returns `True` if anything is modified from the original input stream, otherwise `False`.
@@ -215,7 +231,7 @@ def check_stream(
     config: Config = DEFAULT_CONFIG,
     file_path: Optional[Path] = None,
     disregard_skip: bool = False,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> bool:
     """Checks any imports within the provided code stream, returning `False` if any unsorted or
     incorrectly imports are found or `True` if no problems are identified.
@@ -282,7 +298,7 @@ def check_file(
     file_path: Optional[Path] = None,
     disregard_skip: bool = True,
     extension: Optional[str] = None,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> bool:
     """Checks any imports within the provided file, returning `False` if any unsorted or
     incorrectly imports are found or `True` if no problems are identified.
@@ -335,7 +351,7 @@ def sort_file(
     show_diff: Union[bool, TextIO] = False,
     write_to_stdout: bool = False,
     output: Optional[TextIO] = None,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> bool:
     """Sorts and formats any groups of imports imports within the provided file or Path.
      Returns `True` if the file has been changed, otherwise `False`.
@@ -458,7 +474,7 @@ def find_imports_in_code(
     file_path: Optional[Path] = None,
     unique: Union[bool, ImportKey] = False,
     top_only: bool = False,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> Iterator[identify.Import]:
     """Finds and returns all imports within the provided code string.
 
@@ -486,7 +502,7 @@ def find_imports_in_stream(
     unique: Union[bool, ImportKey] = False,
     top_only: bool = False,
     _seen: Optional[Set[str]] = None,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> Iterator[identify.Import]:
     """Finds and returns all imports within the provided code stream.
 
@@ -527,7 +543,7 @@ def find_imports_in_file(
     file_path: Optional[Path] = None,
     unique: Union[bool, ImportKey] = False,
     top_only: bool = False,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> Iterator[identify.Import]:
     """Finds and returns all imports within the provided source file.
 
@@ -556,7 +572,7 @@ def find_imports_in_paths(
     file_path: Optional[Path] = None,
     unique: Union[bool, ImportKey] = False,
     top_only: bool = False,
-    **config_kwargs,
+    **config_kwargs: Any,
 ) -> Iterator[identify.Import]:
     """Finds and returns all imports within the provided source paths.
 
@@ -581,7 +597,7 @@ def find_imports_in_paths(
 
 
 def _config(
-    path: Optional[Path] = None, config: Config = DEFAULT_CONFIG, **config_kwargs
+    path: Optional[Path] = None, config: Config = DEFAULT_CONFIG, **config_kwargs: Any
 ) -> Config:
     if path and (
         config is DEFAULT_CONFIG

isort/core.py

@@ -445,7 +445,7 @@ def process(
     return made_changes
 
 
-def _indented_config(config: Config, indent: str):
+def _indented_config(config: Config, indent: str) -> Config:
     if not indent:
         return config
 

isort/deprecated/finders.py

@@ -19,19 +19,19 @@
 from isort.utils import exists_case_sensitive
 
 try:
-    from pipreqs import pipreqs
+    from pipreqs import pipreqs  # type: ignore
 
 except ImportError:
     pipreqs = None
 
 try:
-    from pip_api import parse_requirements
+    from pip_api import parse_requirements  # type: ignore
 
 except ImportError:
     parse_requirements = None
 
 try:
-    from requirementslib import Pipfile
+    from requirementslib import Pipfile  # type: ignore
 
 except ImportError:
     Pipfile = None

isort/format.py

@@ -6,7 +6,7 @@
 from typing import Optional, TextIO
 
 try:
-    import colorama
+    import colorama  # type: ignore
 except ImportError:
     colorama_unavailable = True
 else:
@@ -48,7 +48,7 @@ def show_unified_diff(
     file_path: Optional[Path],
     output: Optional[TextIO] = None,
     color_output: bool = False,
-):
+) -> None:
     """Shows a unified_diff for the provided input and output against the provided file path.
 
     - **file_input**: A string that represents the contents of a file before changes.
@@ -125,7 +125,7 @@ def __init__(self, error: str, success: str, output: Optional[TextIO]):
     def style_text(text: str, style: Optional[str] = None) -> str:
         if style is None:
             return text
-        return style + text + colorama.Style.RESET_ALL
+        return style + text + str(colorama.Style.RESET_ALL)
 
     def diff_line(self, line: str) -> None:
         style = None
@@ -138,7 +138,7 @@ def diff_line(self, line: str) -> None:
 
 def create_terminal_printer(
     color: bool, output: Optional[TextIO] = None, error: str = "", success: str = ""
-):
+) -> BasicPrinter:
     if color and colorama_unavailable:
         no_colorama_message = (
             "\n"

isort/identify.py

@@ -32,7 +32,7 @@ def statement(self) -> str:
             import_string += f" as {self.alias}"
         return import_string
 
-    def __str__(self):
+    def __str__(self) -> str:
         return (
             f"{self.file_path or ''}:{self.line_number} "
             f"{'indented ' if self.indented else ''}{self.statement()}"

isort/io.py

@@ -4,7 +4,7 @@
 from contextlib import contextmanager
 from io import BytesIO, StringIO, TextIOWrapper
 from pathlib import Path
-from typing import Callable, Iterator, TextIO, Union
+from typing import Any, Callable, Iterator, TextIO, Union
 
 from isort._future import dataclass
 from isort.exceptions import UnsupportedEncoding
@@ -19,7 +19,7 @@ class File:
     encoding: str
 
     @staticmethod
-    def detect_encoding(filename: str, readline: Callable[[], bytes]):
+    def detect_encoding(filename: Union[str, Path], readline: Callable[[], bytes]) -> str:
         try:
             return tokenize.detect_encoding(readline)[0]
         except Exception:
@@ -33,11 +33,11 @@ def from_contents(contents: str, filename: str) -> "File":
         )
 
     @property
-    def extension(self):
+    def extension(self) -> str:
         return self.path.suffix.lstrip(".")
 
     @staticmethod
-    def _open(filename):
+    def _open(filename: Union[str, Path]) -> TextIOWrapper:
         """Open a file in read only mode using the encoding detected by
         detect_encoding().
         """
@@ -66,7 +66,7 @@ def read(filename: Union[str, Path]) -> Iterator["File"]:
 
 
 class _EmptyIO(StringIO):
-    def write(self, *args, **kwargs):  # skipcq: PTC-W0049
+    def write(self, *args: Any, **kwargs: Any) -> None:  # type: ignore # skipcq: PTC-W0049
         pass
 
 

isort/literal.py

@@ -69,10 +69,14 @@ def assignment(code: str, sort_type: str, extension: str, config: Config = DEFAU
     return sorted_value_code
 
 
-def register_type(name: str, kind: type):
+def register_type(
+    name: str, kind: type
+) -> Callable[[Callable[[Any, ISortPrettyPrinter], str]], Callable[[Any, ISortPrettyPrinter], str]]:
     """Registers a new literal sort type."""
 
-    def wrap(function):
+    def wrap(
+        function: Callable[[Any, ISortPrettyPrinter], str]
+    ) -> Callable[[Any, ISortPrettyPrinter], str]:
         type_mapping[name] = (kind, function)
         return function
 
@@ -81,7 +85,7 @@ def wrap(function):
 
 @register_type("dict", dict)
 def _dict(value: Dict[Any, Any], printer: ISortPrettyPrinter) -> str:
-    return printer.pformat(dict(sorted(value.items(), key=lambda item: item[1])))
+    return printer.pformat(dict(sorted(value.items(), key=lambda item: item[1])))  # type: ignore
 
 
 @register_type("list", list)

isort/main.py

@@ -7,15 +7,16 @@
 from gettext import gettext as _
 from io import TextIOWrapper
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Sequence
+from typing import Any, Dict, List, Optional, Sequence, Union
 from warnings import warn
 
 from . import __version__, api, files, sections
 from .exceptions import FileSkipped, ISortError, UnsupportedEncoding
 from .format import create_terminal_printer
 from .logo import ASCII_ART
 from .profiles import profiles
-from .settings import VALID_PY_TARGETS, Config, WrapModes
+from .settings import VALID_PY_TARGETS, Config
+from .wrap_modes import WrapModes
 
 try:
     from .setuptools_commands import ISortCommand  # noqa: F401
@@ -920,16 +921,16 @@ def parse_args(argv: Optional[Sequence[str]] = None) -> Dict[str, Any]:
     return arguments
 
 
-def _preconvert(item):
+def _preconvert(item: Any) -> Union[str, List[Any]]:
     """Preconverts objects from native types into JSONifyiable types"""
     if isinstance(item, (set, frozenset)):
         return list(item)
     if isinstance(item, WrapModes):
-        return item.name
+        return str(item.name)
     if isinstance(item, Path):
         return str(item)
     if callable(item) and hasattr(item, "__name__"):
-        return item.__name__
+        return str(item.__name__)
     raise TypeError("Unserializable object {} of type {}".format(item, type(item)))
 
 

isort/output.py

@@ -1,7 +1,7 @@
 import copy
 import itertools
 from functools import partial
-from typing import Iterable, List, Set, Tuple
+from typing import Any, Iterable, List, Optional, Set, Tuple, Type
 
 from isort.format import format_simplified
 
@@ -609,19 +609,21 @@ def _normalize_empty_lines(lines: List[str]) -> List[str]:
 class _LineWithComments(str):
     comments: List[str]
 
-    def __new__(cls, value: str, comments: List[str]):
-        instance = super().__new__(cls, value)  # type: ignore
+    def __new__(
+        cls: Type["_LineWithComments"], value: Any, comments: List[str]
+    ) -> "_LineWithComments":
+        instance = super().__new__(cls, value)
         instance.comments = comments
         return instance
 
 
-def _ensure_newline_before_comment(output):
+def _ensure_newline_before_comment(output: List[str]) -> List[str]:
     new_output: List[str] = []
 
-    def is_comment(line):
-        return line and line.startswith("#")
+    def is_comment(line: Optional[str]) -> bool:
+        return line.startswith("#") if line else False
 
-    for line, prev_line in zip(output, [None] + output):
+    for line, prev_line in zip(output, [None] + output):  # type: ignore
         if is_comment(line) and prev_line != "" and not is_comment(prev_line):
             new_output.append("")
         new_output.append(line)