Version 0.0.5 release

Changes:
1. Now checking aliases' names inside imports, closes #65
2. Adds `generator_stop` to the whitelist of future imports, closes #64
3. Adds `CONTRIBUTING.md`, closes #62
4. Refactors how errors are yielded, closes #61
5. Fixes `wemake.services` badge, closes #59
6. Restricts dotted raw imports, closes #56

CHANGELOG.md

@@ -2,6 +2,19 @@
 
 We follow Semantic Versions.
 
+## Version 0.0.5
+
+### Features
+
+- We now allow `generator_stop` to be a `__future__` import
+- We now restrict dotted raw imports like: `import os.path`
+- We now check import aliases as regular variable names
+
+### Misc
+
+- We have added a `CONTRIBUTING.md` file to help new contributors
+
+
 ## Version 0.0.4
 
 ### Features

CONTRIBUTING.md

@@ -0,0 +1,69 @@
+# How to contribute
+
+If you want to start working on this project,
+you will need to get familiar with these APIs:
+
+- [Writing a `flake8` plugin](http://flake8.pycqa.org/en/latest/plugin-development/)
+- [Using `ast` module](https://docs.python.org/3/library/ast.html)
+
+It is also recommended to take a look at these resources:
+
+- [Missing `ast` guide](https://greentreesnakes.readthedocs.io/en/latest/)
+
+
+## Dependencies
+
+We use [`poetry`](https://github.com/sdispater/poetry) to manage the dependencies.
+
+To install them you would need to run two commands:
+
+```bash
+poetry install
+poetry develop
+```
+
+To activate your `virtualenv` run `poetry shell`.
+
+
+## Tests
+
+We use `pytest` and `flake8` for quality control.
+To run all tests:
+
+```bash
+pytest
+```
+
+This step is mandatory during the CI.
+
+
+## Type checks
+
+We use `mypy` to run type checks on our code.
+To use it:
+
+```bash
+mypy wemake_python_styleguide
+```
+
+This step is mandatory during the CI.
+
+
+## Before submitting
+
+Before submitting your code please do the following steps:
+
+1. Run `pytest` to make sure everything was working before
+2. Add any changes you want
+3. Adds tests for the new changes
+4. Edit documentation if you have changed something significant
+5. Run `pytest` again to make sure it is still working
+6. Run `mypy` to ensure that types are correct
+
+
+## Other help
+
+You can contribute by spreading a word about this library.
+It would also be a huge contribution to write
+a short article on how you are using this project.
+What are your best-practices?

README.md

@@ -1,6 +1,6 @@
 # wemake-python-styleguide
 
-[![wemake.services](https://img.shields.io/badge/style-wemake.services-green.svg?label=&logo=data%3Aimage%2Fpng%3Bbase64%2CiVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAMAAAAoLQ9TAAAABGdBTUEAALGPC%2FxhBQAAAAFzUkdCAK7OHOkAAAAbUExURQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP%2F%2F%2F5TvxDIAAAAIdFJOUwAjRA8xXANAL%2Bv0SAAAADNJREFUGNNjYCAIOJjRBdBFWMkVQeGzcHAwksJnAPPZGOGAASzPzAEHEGVsLExQwE7YswCb7AFZSF3bbAAAAABJRU5ErkJggg%3D%3D)](http://wemake.services)
+[![wemake.services](https://img.shields.io/badge/-wemake.services-green.svg?label=&logo=data%3Aimage%2Fpng%3Bbase64%2CiVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAMAAAAoLQ9TAAAABGdBTUEAALGPC%2FxhBQAAAAFzUkdCAK7OHOkAAAAbUExURQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP%2F%2F%2F5TvxDIAAAAIdFJOUwAjRA8xXANAL%2Bv0SAAAADNJREFUGNNjYCAIOJjRBdBFWMkVQeGzcHAwksJnAPPZGOGAASzPzAEHEGVsLExQwE7YswCb7AFZSF3bbAAAAABJRU5ErkJggg%3D%3D)](https://wemake.services)
 [![Build Status](https://travis-ci.org/wemake-services/wemake-python-styleguide.svg?branch=master)](https://travis-ci.org/wemake-services/wemake-python-styleguide)
 [![Coverage](https://coveralls.io/repos/github/wemake-services/wemake-python-styleguide/badge.svg?branch=master)](https://coveralls.io/github/wemake-services/wemake-python-styleguide?branch=master)
 [![PyPI version](https://badge.fury.io/py/wemake-python-styleguide.svg)](https://badge.fury.io/py/wemake-python-styleguide)
@@ -9,6 +9,9 @@
 
 Welcome to the most opinionated linter ever.
 
+`wemake-python-styleguide` is actually just a `flake8` plugin.
+The main goal of this tool is to make our `python` code consistent.
+
 
 ## Installation
 

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "wemake-python-styleguide"
-version = "0.0.4"
+version = "0.0.5"
 description = "Opinionated styleguide that we use in wemake.services"
 
 license = "MIT"

tests/test_visitors/test_wrong_import/test_dotted_raw_import.py

@@ -0,0 +1,79 @@
+# -*- coding: utf-8 -*-
+
+import pytest
+
+from wemake_python_styleguide.visitors.wrong_import import (
+    DottedRawImportViolation,
+    WrongImportVisitor,
+)
+
+regular_import = """
+import {0}
+"""
+
+regular_import_with_alias = """
+import {0} as alias
+"""
+
+from_import = """
+from {0} import some
+"""
+
+from_import_with_alias = """
+from {0} import some as alias
+"""
+
+
+@pytest.mark.parametrize('code', [
+    regular_import,
+    regular_import_with_alias,
+])
+@pytest.mark.parametrize('to_import', [
+    'dotted.path'
+    'nested.dotted.path',
+])
+def test_wrong_dotted_import(assert_errors, parse_ast_tree, code, to_import):
+    """Testing that dotted raw imports are restricted."""
+    tree = parse_ast_tree(code.format(to_import))
+
+    visiter = WrongImportVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [DottedRawImportViolation])
+
+
+@pytest.mark.parametrize('code', [
+    regular_import,
+    regular_import_with_alias,
+])
+@pytest.mark.parametrize('to_import', [
+    'os',
+    'sys',
+])
+def test_correct_flat_import(assert_errors, parse_ast_tree, code, to_import):
+    """Testing that flat raw imports are allowed."""
+    tree = parse_ast_tree(code.format(to_import))
+
+    visiter = WrongImportVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [])
+
+
+@pytest.mark.parametrize('code', [
+    from_import,
+    from_import_with_alias,
+])
+@pytest.mark.parametrize('to_import', [
+    'regular',
+    'dotted.path'
+    'nested.dotted.path',
+])
+def test_regular_from_import(assert_errors, parse_ast_tree, code, to_import):
+    """Testing that dotted `from` imports are allowed."""
+    tree = parse_ast_tree(code.format(to_import))
+
+    visiter = WrongImportVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [])

tests/test_visitors/test_wrong_name/test_function_names.py

@@ -63,7 +63,7 @@ def test_too_short_function_names(
 def test_private_function_names(
     assert_errors, parse_ast_tree, code,
 ):
-    """Testing that function can not have too short names."""
+    """Testing that function can not have private names."""
     tree = parse_ast_tree(code.format('__hidden'))
 
     visiter = WrongNameVisitor()
@@ -83,7 +83,7 @@ def test_private_function_names(
     function_bad_name,
     method_bad_name,
 ])
-def test_correct_function_name(
+def test_correct_function_names(
     assert_errors, parse_ast_tree, correct_name, code,
 ):
     """Testing that function can have normal names."""

tests/test_visitors/test_wrong_name/test_import_alias.py

@@ -0,0 +1,93 @@
+# -*- coding: utf-8 -*-
+
+import string
+
+import pytest
+
+from wemake_python_styleguide.visitors.wrong_name import (
+    BAD_VARIABLE_NAMES,
+    PrivateNameViolation,
+    TooShortVariableNameViolation,
+    WrongNameVisitor,
+    WrongVariableNameViolation,
+)
+
+import_alias = """
+import os as {0}
+"""
+
+from_import_alias = """
+from os import path as {0}
+"""
+
+
+@pytest.mark.parametrize('bad_name', BAD_VARIABLE_NAMES)
+@pytest.mark.parametrize('code', [
+    import_alias,
+    from_import_alias,
+])
+def test_wrong_import_alias_names(
+    assert_errors, parse_ast_tree, bad_name, code,
+):
+    """Testing that import aliases can not have blacklisted names."""
+    tree = parse_ast_tree(code.format(bad_name))
+
+    visiter = WrongNameVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [WrongVariableNameViolation])
+
+
+@pytest.mark.parametrize('short_name', string.ascii_letters)
+@pytest.mark.parametrize('code', [
+    import_alias,
+    from_import_alias,
+])
+def test_too_short_import_alias_names(
+    assert_errors, parse_ast_tree, short_name, code,
+):
+    """Testing that import aliases can not have too short names."""
+    tree = parse_ast_tree(code.format(short_name))
+
+    visiter = WrongNameVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [TooShortVariableNameViolation])
+
+
+@pytest.mark.parametrize('code', [
+    import_alias,
+    from_import_alias,
+])
+def test_private_import_alias_names(
+    assert_errors, parse_ast_tree, code,
+):
+    """Testing that import aliases can not have too private names."""
+    tree = parse_ast_tree(code.format('__hidden'))
+
+    visiter = WrongNameVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [PrivateNameViolation])
+
+
+@pytest.mark.parametrize('correct_name', [
+    'my_alias',
+    'xy',
+    'test',
+    '_protected',
+])
+@pytest.mark.parametrize('code', [
+    import_alias,
+    from_import_alias,
+])
+def test_correct_import_alias_names(
+    assert_errors, parse_ast_tree, correct_name, code,
+):
+    """Testing that import aliases can have normal names."""
+    tree = parse_ast_tree(code.format(correct_name))
+
+    visiter = WrongNameVisitor()
+    visiter.visit(tree)
+
+    assert_errors(visiter, [])

wemake_python_styleguide/checker.py

@@ -77,5 +77,4 @@ def run(self) -> Generator[CheckResult, None, None]:
             visiter.visit(self.tree)
 
             for error in visiter.errors:
-                lineno, col_offset, message = error.node_items()
-                yield lineno, col_offset, message, type(self)
+                yield (*error.node_items(), type(self))

wemake_python_styleguide/constants.py

@@ -91,4 +91,5 @@
 #: List of allowed ``__future__`` imports.
 FUTURE_IMPORTS_WHITELIST = frozenset((
     'annotations',
+    'generator_stop',
 ))

wemake_python_styleguide/errors.py

@@ -127,6 +127,27 @@ class FutureImportViolation(BaseStyleViolation):
     _code = 'Z102'
 
 
+class DottedRawImportViolation(BaseStyleViolation):
+    """
+    This rule forbids to use imports like ``import os.path``.
+
+    Example::
+
+        # Correct:
+        from os import path
+
+        # Wrong:
+        import os.path
+
+    Note:
+        Returns Z103 as error code
+
+    """
+
+    _error_tmpl = '{0} Found dotted raw import "{1}"'
+    _code = 'Z103'
+
+
 class WrongKeywordViolation(BaseStyleViolation):
     """
     This rule forbids to use some keywords from ``python``.

wemake_python_styleguide/visitors/wrong_import.py

@@ -4,6 +4,7 @@
 
 from wemake_python_styleguide.constants import FUTURE_IMPORTS_WHITELIST
 from wemake_python_styleguide.errors import (
+    DottedRawImportViolation,
     FutureImportViolation,
     LocalFolderImportViolation,
     NestedImportViolation,
@@ -42,13 +43,19 @@ def _check_future_import(self, node: ast.ImportFrom):
                         FutureImportViolation(node, text=alias.name),
                     )
 
+    def _check_dotted_raw_import(self, node: ast.Import):
+        for alias in node.names:
+            if '.' in alias.name:
+                self.add_error(DottedRawImportViolation(node, text=alias.name))
+
     def visit_Import(self, node: ast.Import):
-        """Used to find nested `import` statements."""
+        """Used to find wrong `import` statements."""
         self._check_nested_import(node)
+        self._check_dotted_raw_import(node)
         self.generic_visit(node)
 
     def visit_ImportFrom(self, node: ast.ImportFrom):
-        """Used to find nested `from import` statements and local imports."""
+        """Used to find wrong `from import` statements."""
         self._check_local_import(node)
         self._check_nested_import(node)
         self._check_future_import(node)