[REF] import-checkers: Use of isort (#879)

Use the isort library for wrong-import-order checker.

9 files changed, 61 insertions, 31 deletions

diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index 99105e56c..1de7fc424 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -84,6 +84,7 @@ Order doesn't matter (not that much, at least ;)
 
 * Łukasz Rogalski: invalid-length-returned
 
-* Moisés López (Vauxoo): Support for deprecated-modules in modules not installed.
+* Moisés López (Vauxoo): Support for deprecated-modules in modules not installed,
+  Refactory wrong-import-order to integrate it with `isort` library.
 
 * Luis Escobar (Vauxoo), Moisés López (Vauxoo): Add bad-docstring-quotes and docstring-first-line-empty
diff --git a/README.rst b/README.rst
index 7159110f4..a36072f94 100644
--- a/README.rst
+++ b/README.rst
@@ -40,6 +40,14 @@ Installation should be as simple as ::
 

     python -m pip install astroid

 

+Pylint requires isort package (the later the better).

+

+* https://github.com/timothycrosley/isort

+

+Installation should be as simple as ::

+

+    python -m pip install isort

+

 

 If you want to install from a source distribution, extract the tarball and run

 the following commands ::

diff --git a/pylint/__pkginfo__.py b/pylint/__pkginfo__.py
index e8e748159..24370ecad 100644
--- a/pylint/__pkginfo__.py
+++ b/pylint/__pkginfo__.py
@@ -29,6 +29,7 @@ version = '.'.join([str(num) for num in numversion])
 install_requires = [
     'astroid >= 1.5.0,<1.6.0',
     'six',
+    'isort >= 4.2.5',
 ]
 
 if sys.platform == 'win32':
diff --git a/pylint/checkers/imports.py b/pylint/checkers/imports.py
index 9d7291f1e..9a6ea2e6c 100644
--- a/pylint/checkers/imports.py
+++ b/pylint/checkers/imports.py
@@ -24,8 +24,8 @@ import six
 
 import astroid
 from astroid import are_exclusive
-from astroid.modutils import (get_module_part, is_standard_module,
-                              file_from_modpath)
+from astroid.modutils import (get_module_part, is_standard_module)
+import isort
 
 from pylint.interfaces import IAstroidChecker
 from pylint.utils import EmptyReport, get_global_option
@@ -224,6 +224,11 @@ MSGS = {
               'Used when code and imports are mixed'),
     }
 
+
+DEFAULT_STANDARD_LIBRARY = ()
+DEFAULT_KNOWN_THIRD_PARTY = ('enchant',)
+
+
 class ImportsChecker(BaseChecker):
     """checks for
     * external modules dependencies
@@ -270,6 +275,21 @@ given file (report RP0402 must not be disabled)'}
                  'help' : 'Create a graph of internal dependencies in the \
 given file (report RP0402 must not be disabled)'}
                ),
+               ('known-standard-library',
+                {'default': DEFAULT_STANDARD_LIBRARY,
+                 'type': 'csv',
+                 'metavar': '<modules>',
+                 'help': 'Force import order to recognize a module as part of' \
+                         ' the standard compatibility libraries.'}
+               ),
+               ('known-third-party',
+                {'default': DEFAULT_KNOWN_THIRD_PARTY,
+                 'type': 'csv',
+                 'metavar': '<modules>',
+                 'help': 'Force import order to recognize a module as part of' \
+                         ' a third party library.'}
+               ),
+
               )
 
     def __init__(self, linter=None):
@@ -466,7 +486,10 @@ given file (report RP0402 must not be disabled)'}
         """Record the package `node` imports from"""
         importedname = importedmodnode.name if importedmodnode else None
         if not importedname:
-            importedname = node.names[0][0].split('.')[0]
+            if isinstance(node, astroid.ImportFrom):
+                importedname = node.modname
+            else:
+                importedname = node.names[0][0].split('.')[0]
         self._imports_stack.append((node, importedname))
 
     @staticmethod
@@ -483,36 +506,31 @@ given file (report RP0402 must not be disabled)'}
         extern_imports = []
         local_imports = []
         std_imports = []
+        isort_obj = isort.SortImports(
+            file_contents='', known_third_party=self.config.known_third_party,
+            known_standard_library=self.config.known_standard_library,
+        )
         for node, modname in self._imports_stack:
             package = modname.split('.')[0]
-            if is_standard_module(modname):
+            import_category = isort_obj.place_module(package)
+            if import_category in ('FUTURE', 'STDLIB'):
                 std_imports.append((node, package))
                 wrong_import = extern_imports or local_imports
-                if not wrong_import:
-                    continue
                 if self._is_fallback_import(node, wrong_import):
                     continue
-                self.add_message('wrong-import-order', node=node,
-                                 args=('standard import "%s"' % node.as_string(),
-                                       '"%s"' % wrong_import[0][0].as_string()))
-            else:
-                try:
-                    filename = file_from_modpath([package])
-                except ImportError:
-                    continue
-                if not filename:
-                    continue
-
-                filename = os.path.normcase(os.path.abspath(filename))
-                if not any(filename.startswith(path) for path in self._site_packages):
-                    local_imports.append((node, package))
-                    continue
+                if wrong_import:
+                    self.add_message('wrong-import-order', node=node,
+                                     args=('standard import "%s"' % node.as_string(),
+                                           '"%s"' % wrong_import[0][0].as_string()))
+            elif import_category in ('FIRSTPARTY', 'THIRDPARTY'):
                 extern_imports.append((node, package))
-                if not local_imports:
-                    continue
-                self.add_message('wrong-import-order', node=node,
-                                 args=('external import "%s"' % node.as_string(),
-                                       '"%s"' % local_imports[0][0].as_string()))
+                wrong_import = local_imports
+                if wrong_import:
+                    self.add_message('wrong-import-order', node=node,
+                                     args=('external import "%s"' % node.as_string(),
+                                           '"%s"' % wrong_import[0][0].as_string()))
+            elif import_category == 'LOCALFOLDER':
+                local_imports.append((node, package))
         return std_imports, extern_imports, local_imports
 
     def _get_imported_module(self, importnode, modname):
diff --git a/pylint/test/functional/import_error.py b/pylint/test/functional/import_error.py
index de72e2fcd..8f7bb3f30 100644
--- a/pylint/test/functional/import_error.py
+++ b/pylint/test/functional/import_error.py
@@ -1,5 +1,5 @@
 """ Test that import errors are detected. """

-# pylint: disable=invalid-name, unused-import, no-absolute-import, bare-except, broad-except

+# pylint: disable=invalid-name, unused-import, no-absolute-import, bare-except, broad-except, wrong-import-order

 import totally_missing # [import-error]

 

 try:

diff --git a/pylint/test/functional/reimported.py b/pylint/test/functional/reimported.py
index 3651fa63d..b73f1ce08 100644
--- a/pylint/test/functional/reimported.py
+++ b/pylint/test/functional/reimported.py
@@ -1,4 +1,4 @@
-# pylint: disable=missing-docstring,unused-import,import-error, wildcard-import,unused-wildcard-import,redefined-builtin,no-name-in-module,ungrouped-imports

+# pylint: disable=missing-docstring,unused-import,import-error, wildcard-import,unused-wildcard-import,redefined-builtin,no-name-in-module,ungrouped-imports,wrong-import-order

 

 from time import sleep, sleep # [reimported]

 from lala import missing, missing # [reimported]

diff --git a/pylint/test/functional/super_checks.py b/pylint/test/functional/super_checks.py
index 2959d0023..42a933386 100644
--- a/pylint/test/functional/super_checks.py
+++ b/pylint/test/functional/super_checks.py
@@ -1,4 +1,4 @@
-# pylint: disable=too-few-public-methods,import-error, no-absolute-import,missing-docstring, wrong-import-position,invalid-name
+# pylint: disable=too-few-public-methods,import-error, no-absolute-import,missing-docstring, wrong-import-position,invalid-name, wrong-import-order
 """check use of super"""
 
 from unknown import Missing
diff --git a/pylint/test/input/func_w0404.py b/pylint/test/input/func_w0404.py
index 5111c6036..2ce7d651c 100644
--- a/pylint/test/input/func_w0404.py
+++ b/pylint/test/input/func_w0404.py
@@ -9,7 +9,7 @@ from xml.etree import ElementTree
 from email import encoders
 import email.encoders
 
-import sys  #pylint: disable=ungrouped-imports
+import sys  #pylint: disable=ungrouped-imports,wrong-import-order
 __revision__ = 0
 
 def no_reimport():
diff --git a/tox.ini b/tox.ini
index 8c083e8dd..f8db27d11 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,6 +5,7 @@ skip_missing_interpreters = true
 [testenv:pylint]
 deps =
    git+https://github.com/PyCQA/astroid@master
+   isort
 
 commands = pylint -rn --rcfile={toxinidir}/pylintrc {envsitepackagesdir}/pylint
 
@@ -12,6 +13,7 @@ commands = pylint -rn --rcfile={toxinidir}/pylintrc {envsitepackagesdir}/pylint
 deps =
    git+https://github.com/PyCQA/astroid@master
    coverage
+   isort
 
 setenv =
     COVERAGE_FILE = {toxinidir}/.coverage.{envname}