Issue #1172 (#1199)

* Add ExecutableMismatchViolation #9

* Add logic for ExecutableMismatch

* Add WPS452 to test_noqa.py #5

* Remove dependency and related test

* Implement the full checking logic (#13)

* Fix linting problem (#14)

* Clean up code (#15)

Fix checking logic so that we don't thoroughly check every comment

* Fix permissions (#16)

* Make a new visitor to handle files with 0 comments (#17)

* Add tests for ExecutableMismatchViolation (#18)

* Add ExecutableMismatchViolation #9

* Add WPS452 to test_noqa.py #5

* Remove dependency and related test

* Add test resource files from flake8-executable

* Add tests for check_valid_shebang #7

* Implement the full checking logic (#13)

* Fix linting problem (#14)

* Clean up code (#15)

Fix checking logic so that we don't thoroughly check every comment

* Fix permissions (#16)

* Ignore failing test files

* Update test file to be compatible with the new visitor

* Fix linter issues

* Make a new visitor to handle files with 0 comments (#17)

* Exclude test files from linting

Co-authored-by: Hanzhang <48179160+hanzhsun@users.noreply.github.com>
Co-authored-by: jrutqvist <joar.rutqvist@gmail.com>
Co-authored-by: Gabriel Chang <Gc.chang95@gmail.com>

* Update CHANGELOG.md

* Moved test resources to fixtures to be ignored by autopep8

* Add integration test

* Refactor tests

* Make the requested changes
Use temporary files for testing

* Update noqa.py

* Make additional requested changes

* Fix small formatting and typing issues

* Update comments.py

* Update comments.py

Co-authored-by: hanzhsu <emily_1999@link.cuhk.edu.hk>
Co-authored-by: Gabriel Chang <Gc.chang95@gmail.com>
Co-authored-by: Hanzhang <48179160+hanzhsun@users.noreply.github.com>
Co-authored-by: jrutqvist <joar.rutqvist@gmail.com>
Co-authored-by: Nikita Sobolev <mail@sobolevn.me>

CHANGELOG.md

@@ -13,6 +13,7 @@ Semantic versioning in our case means:
 
 ### Features
 
+- **Breaking**: removes `flake8-executable`, now using `WPS452` instead of `EXE001..EXE005`
 - **Breaking**: removes `flake8-print`, now using `WPS421` instead of `T001`
 - **Breaking**: removes `flake8-annotations-complexity`,
   now using `WPS234` instead of `TAE002`

docs/pages/usage/violations/index.rst

@@ -46,7 +46,6 @@ flake8-pep3101                 `S001 <https://github.com/gforcada/flake8-pep3101
 flake8-bandit                  `S100 - S710 <https://github.com/tylerwince/flake8-bandit>`_, see also original ``bandit`` `codes <https://bandit.readthedocs.io/en/latest/plugins/index.html#complete-test-plugin-listing>`_
 flake8-debugger                `T100 <https://github.com/JBKahn/flake8-debugger/blob/master/flake8_debugger.py>`_
 flake8-rst-docstrings          `RST201 - RST499 <https://github.com/peterjc/flake8-rst-docstrings>`_
-flake8-executable              `EXE001 - EXE005 <https://github.com/xuhdev/flake8-executable>`_
 darglint                       `DAR001 - DAR501 <https://github.com/terrencepreilly/darglint#error-codes>`_
 wemake-python-styleguide       WPS, defined here
 =============================  ======

pyproject.toml

@@ -74,7 +74,6 @@ flake8-eradicate = "^0.2"
 flake8-bandit = "^2.1"
 flake8-broken-line = "^0.1"
 flake8-rst-docstrings = "^0.0.12"
-flake8-executable = "^2.0"
 pep8-naming = "^0.9.1"
 darglint = "^1.1"
 

tests/fixtures/external_plugins.py

@@ -1,4 +1,3 @@
-#!/usr/bin/env perl
 from sys import *
 import sys
 from typing import List, Union, Dict

tests/plugins/tokenize_parser.py

@@ -12,3 +12,13 @@ def factory(code: str):
         lines = io.StringIO(dedent(code))
         return list(tokenize.generate_tokens(lambda: next(lines)))
     return factory
+
+
+@pytest.fixture(scope='session')
+def parse_file_tokens(parse_tokens):
+    """Parses tokens from a file."""
+    def factory(filename: str):
+        with open(filename, 'r', encoding='utf-8') as test_file:
+            file_content = test_file.read()
+            return parse_tokens(file_content)
+    return factory

tests/test_checker/test_noqa.py

@@ -217,6 +217,7 @@
     'WPS450': 1,
     'WPS451': 0,  # defined in version specific table.
     'WPS452': 1,  # also defined in version specific table.
+    'WPS453': 0,
 
     'WPS500': 1,
     'WPS501': 1,

tests/test_plugins.py

@@ -29,7 +29,6 @@
     'S101',  # flake8-bandit
     'T100',  # flake8-debugger
     'RST215',  # flake8-rst-docstrings
-    'EXE003',  # flake8-executable
     'DAR101',  # darglint
 )
 

tests/test_visitors/test_tokenize/test_comments/conftest.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+
+from os import chmod
+
+import pytest
+
+TEMP_FOLDER = 'tmp'
+MODE_EXECUTABLE = 0o755
+MODE_NON_EXECUTABLE = 0o644
+
+
+@pytest.fixture()
+def make_file(tmp_path):
+    """Fixture to make a temporary executable or non executable file."""
+    def factory(
+        filename: str,
+        file_content: str,
+        is_executable: bool,
+    ) -> str:
+        temp_folder = tmp_path / TEMP_FOLDER
+        temp_folder.mkdir()
+        test_file = temp_folder / filename
+        file_mode = MODE_EXECUTABLE if is_executable else MODE_NON_EXECUTABLE
+
+        test_file.write_text(file_content)
+        chmod(test_file.as_posix(), file_mode)
+
+        return test_file.as_posix()
+
+    return factory

tests/test_visitors/test_tokenize/test_comments/test_valid_shebang.py

@@ -0,0 +1,197 @@
+# -*- coding: utf-8 -*-
+
+import pytest
+
+from wemake_python_styleguide.violations.best_practices import ShebangViolation
+from wemake_python_styleguide.visitors.tokenize.comments import ShebangVisitor
+
+# Correct
+
+exe001_neg_shouldnt_be_executable = """
+if __name__ == '__main__':
+    print('I am not executable.')
+"""
+
+exe001_neg_executable = False
+exe001_neg_filename = 'exe001_neg.py'
+
+exe002_neg_shouldnt_be_executable = """
+def a_lib_function():
+    print('I am not executable.')
+"""
+
+exe002_neg_executable = False
+exe002_neg_filename = 'exe002_neg.py'
+
+exe003_neg_good_shebang = """#!/usr/bin/python3
+
+if __name__ == '__main__':
+    print('I have a good shebang.')
+"""
+
+exe003_neg_executable = True
+exe003_neg_filename = 'exe003_neg.py'
+
+exe004_neg_no_space_before_shebang = """#!/usr/bin/python3
+
+if __name__ == '__main__':
+    print('I do not have whitespace before shebang.')
+"""
+
+exe004_neg_executable = True
+exe004_neg_filename = 'exe004_neg.py'
+
+exe005_neg_nothing_before_shebang = """#!/usr/bin/python3
+
+if __name__ == '__main__':
+    print('I do not have any blank or comment lines before shebang.')
+"""
+
+exe005_neg_executable = True
+exe005_neg_filename = 'exe005_neg.py'
+
+# Wrong
+
+exe001_pos_should_be_executable = """#!/usr/bin/python
+
+if __name__ == '__main__':
+    print('I should be executable.')
+"""
+
+exe001_pos_executable = False
+exe001_pos_filename = 'exe001_pos.py'
+
+exe002_pos_shouldnt_be_executable = """
+def a_lib_function():
+    print("I shouldn't be executable.")
+"""
+
+exe002_pos_executable = True
+exe002_pos_filename = 'exe002_pos.py'
+
+exe003_pos_good_shebang = """#!/bin/bash
+
+if __name__ == '__main__':
+    print('I have a wrong shebang.')
+"""
+
+exe003_pos_executable = True
+exe003_pos_filename = 'exe003_pos.py'
+
+exe004_pos_no_space_before_shebang = """    #!/usr/bin/python3
+
+if __name__ == '__main__':
+    print('I have whitespace before shebang.')
+"""
+
+exe004_pos_executable = True
+exe004_pos_filename = 'exe004_pos.py'
+
+exe005_pos_nothing_before_shebang = """
+#
+#!/usr/bin/python3
+
+if __name__ == '__main__':
+    print('I have blank and comment lines before shebang.')
+"""
+
+exe005_pos_executable = True
+exe005_pos_filename = 'exe005_pos.py'
+
+
+@pytest.mark.parametrize(('filename', 'file_content', 'executable'), [
+    (
+        exe001_neg_filename,
+        exe001_neg_shouldnt_be_executable,
+        exe001_neg_executable,
+    ),
+    (
+        exe002_neg_filename,
+        exe002_neg_shouldnt_be_executable,
+        exe002_neg_executable,
+    ),
+    (
+        exe003_neg_filename,
+        exe003_neg_good_shebang,
+        exe003_neg_executable,
+    ),
+    (
+        exe004_neg_filename,
+        exe004_neg_no_space_before_shebang,
+        exe004_neg_executable,
+    ),
+    (
+        exe005_neg_filename,
+        exe005_neg_nothing_before_shebang,
+        exe005_neg_executable,
+    ),
+])
+def test_exe_negative(
+    make_file,
+    assert_errors,
+    parse_file_tokens,
+    default_options,
+    filename,
+    file_content,
+    executable,
+):
+    """Testing cases when no errors should be reported."""
+    path_to_file = make_file(filename, file_content, executable)
+    file_tokens = parse_file_tokens(path_to_file)
+
+    visitor = ShebangVisitor(
+        default_options,
+        filename=path_to_file,
+        file_tokens=file_tokens,
+    )
+    visitor.run()
+    assert_errors(visitor, [])
+
+
+@pytest.mark.parametrize(('filename', 'file_content', 'executable'), [
+    (
+        exe001_pos_filename,
+        exe001_pos_should_be_executable,
+        exe001_pos_executable,
+    ),
+    (
+        exe002_pos_filename,
+        exe002_pos_shouldnt_be_executable,
+        exe002_pos_executable,
+    ),
+    (
+        exe003_pos_filename,
+        exe003_pos_good_shebang,
+        exe003_pos_executable,
+    ),
+    (
+        exe004_pos_filename,
+        exe004_pos_no_space_before_shebang,
+        exe004_pos_executable,
+    ),
+    (
+        exe005_pos_filename,
+        exe005_pos_nothing_before_shebang,
+        exe005_pos_executable,
+    ),
+])
+def test_exe_posititve(
+    make_file,
+    assert_errors,
+    parse_file_tokens,
+    default_options,
+    filename,
+    file_content,
+    executable,
+):
+    """Testing cases when no errors should be reported."""
+    path_to_file = make_file(filename, file_content, executable)
+    file_tokens = parse_file_tokens(path_to_file)
+
+    visitor = ShebangVisitor(
+        default_options,
+        filename=path_to_file,
+        file_tokens=file_tokens,
+    )
+    visitor.run()
+    assert_errors(visitor, [ShebangViolation])

wemake_python_styleguide/logic/system.py

@@ -0,0 +1,8 @@
+# -*- coding: utf-8 -*-
+
+import os
+
+
+def is_executable_file(filename: str) -> bool:
+    """Checks if a file is executable."""
+    return os.access(filename, os.X_OK)

wemake_python_styleguide/presets/types/file_tokens.py

@@ -11,6 +11,7 @@
 #: Used to store all token related visitors to be later passed to checker:
 PRESET: Final = (
     comments.WrongCommentVisitor,
+    comments.ShebangVisitor,
 
     syntax.WrongKeywordTokenVisitor,
 

wemake_python_styleguide/violations/best_practices.py

@@ -70,6 +70,7 @@
    ProtectedModuleMemberViolation
    PositionalOnlyArgumentsViolation
    LoopControlFinallyViolation
+   ShebangViolation
 
 Best practices
 --------------
@@ -127,6 +128,7 @@
 .. autoclass:: ProtectedModuleMemberViolation
 .. autoclass:: PositionalOnlyArgumentsViolation
 .. autoclass:: LoopControlFinallyViolation
+.. autoclass:: ShebangViolation
 
 """
 
@@ -2068,3 +2070,39 @@ class LoopControlFinallyViolation(ASTViolation):
 
     error_template = 'Found `break` or `continue` in `finally` block'
     code = 452
+
+
+@final
+class ShebangViolation(SimpleViolation):
+    """
+    Forbids to execute the file with shebang incorrectly set.
+
+    A violation is raised in these cases :
+        - Shebang is present but the file is not executable.
+        - The file is executable but no shebang is present.
+        - Shebang is present but does not contain "python".
+        - There is whitespace before shebang.
+        - There are blank or comment lines before shebang.
+
+    Reasoning:
+        Setting the shebang incorrectly causes executable mismatch.
+
+    Solution:
+        Ensure the shebang is present on the first line,
+        contains "python", and there is no whitespace before.
+
+    Example::
+
+        # Correct:
+        #!/usr/bin/env python
+
+        # Wrong:
+        #!/usr/bin/env
+            #!/usr/bin/env python
+
+    .. versionadded:: 0.14.0
+
+    """
+
+    error_template = 'Found executable mismatch: {0}'
+    code = 453