WIP

flake8_isort.py

@@ -1,16 +1,53 @@
 # -*- coding: utf-8 -*-
 from isort import SortImports
 
+import os
+
 
 class Flake8Isort(object):
     name = 'flake8_isort'
     version = '0.1'
     message = 'I001 found unsorted imports'
 
+    no_config_file = None
+
     def __init__(self, tree, filename):
         self.filename = filename
 
+    @classmethod
+    def add_options(cls, parser):
+        parser.add_option(
+            '--no-isort-config',
+            action='store_true',
+            help='Do not require an .isort.cfg file to be found'
+        )
+        parser.config_options.append('no-isort-config')
+
+    @classmethod
+    def parse_options(cls, options):
+        cls.no_config_file = bool(options.no_isort_config)
+
     def run(self):
-        sort_result = SortImports(self.filename, check=True)
-        if sort_result.incorrectly_sorted:
-            yield 0, 0, self.message, type(self)
+        if not self.no_config_file and not self.search_isort_config():
+            yield 0, 0, 'I002 no .isort.cfg file found', type(self)
+        else:
+            sort_result = SortImports(self.filename, check=True)
+            if sort_result.incorrectly_sorted:
+                yield 0, 0, self.message, type(self)
+
+    def search_isort_config(self):
+        """Search for a .isort.cfg all the way up to the root folder"""
+        full_path = os.path.abspath(self.filename)
+        path_parts = full_path.split(os.path.sep)
+        dirs_missing = len(path_parts)
+
+        while dirs_missing > 0:
+            dirs_missing -= 1
+            partial_parts = path_parts[:dirs_missing]
+            partial_path = os.sep.join(partial_parts)
+
+            isort_file = '{0}{1}.isort.cfg'.format(partial_path, os.sep)
+            if os.path.exists(isort_file):
+                return True
+
+        return False

run_tests.py

@@ -1,9 +1,11 @@
 # -*- coding: utf-8 -*-
+from flake8.engine import get_style_guide
 from flake8_isort import Flake8Isort
 from tempfile import mkdtemp
 from testfixtures import OutputCapture
 
 import os
+import sys
 import unittest
 
 
@@ -49,6 +51,62 @@ def test_sorted_incorrectly(self):
             self.assertEqual(ret[0][1], 0)
             self.assertEqual(ret[0][2], 'I001 found unsorted imports')
 
+    def test_isortcfg_found(self):
+        # _given_a_file_in_test_dir already creates an .isort.cfg file
+        file_path = self._given_a_file_in_test_dir(
+            'from sys import pid\n'
+            'import threading',
+            isort_config='force_single_line=True'
+        )
+        with OutputCapture():
+            checker = Flake8Isort(None, file_path)
+            checker.no_config_file = False
+            ret = list(checker.run())
+            self.assertEqual(len(ret), 1)
+            self.assertEqual(ret[0][0], 0)
+            self.assertEqual(ret[0][1], 0)
+            self.assertEqual(ret[0][2], 'I001 found unsorted imports')
+
+    def test_isortcfg_not_found(self):
+        file_path = self._given_a_file_in_test_dir(
+            'from sys import pid\n'
+            'import threading',
+            isort_config='force_single_line=True'
+        )
+        # remove the .isort.cfg file
+        isortcfg_path = file_path.split('/')[: -1]
+        isortcfg_path = '{0}/.isort.cfg'.format('/'.join(isortcfg_path))
+        os.remove(isortcfg_path)
+
+        with OutputCapture():
+            checker = Flake8Isort(None, file_path)
+            checker.no_config_file = False
+            ret = list(checker.run())
+            self.assertEqual(len(ret), 1)
+            self.assertEqual(ret[0][0], 0)
+            self.assertEqual(ret[0][1], 0)
+            self.assertEqual(ret[0][2], 'I002 no .isort.cfg file found')
+
+    def test_default_option(self):
+        """By default a config file (.isort.cfg) is expected"""
+        _argv = sys.argv
+        try:
+            sys.argv = []
+            get_style_guide(parse_argv=True)  # parse arguments
+            self.assertFalse(Flake8Isort.no_config_file)
+        finally:
+            sys.argv = _argv
+
+    def test_no_config_file(self):
+        """Check that one can force to not look for a config file"""
+        _argv = sys.argv
+        try:
+            sys.argv = ['', '--no-isort-config']
+            get_style_guide(parse_argv=True)  # parse arguments
+            self.assertTrue(Flake8Isort.no_config_file)
+        finally:
+            sys.argv = _argv
+
 
 if __name__ == '__main__':
     unittest.main()