PycodestyleBear: Migrate bear to aspects

This migrates `PycodestyleBear` to its respective
aspects and tastes.

Closes #2656

bears/python/PycodestyleBear.py

@@ -1,15 +1,21 @@
 import sys
+import re
 
 from coalib.bearlib.abstractions.Linter import linter
 from coalib.settings.Setting import typed_list
+from coalib.results.Result import Result
+from coalib.bearlib.aspects import map_setting_to_aspect
+from coalib.bearlib.aspects.Formatting import LineLength
 
 from dependency_management.requirements.PipRequirement import PipRequirement
 
 
+OUTPUT_REGEX = (r'(?P<line>\d+) (?P<column>\d+) '
+                r'(?P<message>(?P<origin>\S+).*)')
+
+
 @linter(executable='pycodestyle',
-        output_format='regex',
-        output_regex=r'(?P<line>\d+) (?P<column>\d+) '
-                     r'(?P<message>(?P<origin>\S+).*)')
+        )
 class PycodestyleBear:
     """
     A wrapper for the tool ``pycodestyle`` formerly known as ``pep8``.
@@ -21,8 +27,11 @@ class PycodestyleBear:
     LICENSE = 'AGPL-3.0'
     CAN_DETECT = {'Formatting'}
 
-    @staticmethod
+    @map_setting_to_aspect(
+        max_line_length=LineLength.max_line_length,
+    )
     def create_arguments(
+            self,
             filename, file, config_file,
             pycodestyle_ignore: typed_list(str) = (
                 'E121', 'E123', 'E126', 'E133', 'E226',
@@ -61,3 +70,21 @@ def create_arguments(
         arguments.append(filename)
 
         return arguments
+
+    def process_output(self, output, filename, file):
+        result = re.match(OUTPUT_REGEX, output)
+        if not result:
+            return
+        line, column, message, rule = result.groups()
+        if rule == 'E501':
+            aspect = LineLength('py')
+        else:
+            aspect = None
+        yield Result.from_values(
+            origin='{} ({})'.format(self.name, rule),
+            message=message,
+            file=filename,
+            line=int(line),
+            column=int(column),
+            aspect=aspect,
+            )

tests/python/PycodestyleBearTest.py

@@ -1,5 +1,15 @@
+import unittest
+
 from bears.python.PycodestyleBear import PycodestyleBear
-from coalib.testing.LocalBearTestHelper import verify_local_bear
+from coalib.testing.LocalBearTestHelper import verify_local_bear, execute_bear
+from coalib.settings.Section import Section
+from coala_utils.ContextManagers import prepare_file
+from queue import Queue
+from coalib.bearlib.aspects.Formatting import LineLength
+from coalib.bearlib.aspects import (
+    AspectList,
+    get as get_aspect,
+)
 
 
 good_file = '''
@@ -45,6 +55,8 @@ def hello():
 
 long_line = 'a = "{0}"'.format('a' * 100)
 
+small_line = 'Small line.'
+
 PycodestyleBearLineLengthTest = verify_local_bear(
     PycodestyleBear,
     valid_files=(),
@@ -63,3 +75,42 @@ def hello():
     valid_files=(file_with_very_long_line,),
     invalid_files=(),
     settings={'max_line_length': 0})
+
+PycodestyleBearAspectsTest = verify_local_bear(
+    PycodestyleBear,
+    valid_files=(small_line,),
+    invalid_files=(long_line,),
+    aspects=AspectList([
+        get_aspect('LineLength')('Python', max_line_length=30),
+    ]),
+)
+
+PycodestyleBearSettingsOverAspectsTest = verify_local_bear(
+    PycodestyleBear,
+    valid_files=(small_line,),
+    invalid_files=(long_line,),
+    aspects=AspectList([
+        get_aspect('LineLength')('Python', max_line_length=2),
+    ]),
+    settings={'max_line_length': 30},
+)
+
+
+class PycodestyleBearTest(unittest.TestCase):
+
+    def setUp(self):
+        self.section = Section('')
+        self.section.aspects = AspectList([
+            get_aspect('LineLength')('Python', max_line_length=30),
+        ])
+        self.uut = PycodestyleBear(self.section, Queue())
+
+    def test_line_length(self):
+        content = long_line.splitlines()
+        with prepare_file(content, None) as (file, fname):
+            with execute_bear(self.uut, fname, file) as results:
+                result = results[0]
+                self.assertEqual(result.message,
+                                 'E501 line too long (106 > 30 characters)')
+                self.assertEqual(result.origin, 'PycodestyleBear (E501)')
+                self.assertEqual(result.aspect, LineLength('py'))