Support isort5

.travis.yml

@@ -1,20 +1,32 @@
 dist: xenial
 language: python
-matrix:
-  - python: '2.7'
-  - python: '3.5'
-  - python: '3.6'
-  - python: '3.7'
-  - python: '3.8'
-  - python: 'pypy'
-  - python: 'pypy3'
+python:
+  - '2.7'
+  - '3.5'
+  - '3.6'
+  - '3.7'
+  - '3.8'
+  - 'pypy'
+  - 'pypy3'
+env:
+  - ISORT_VER="4"
+  - ISORT_VER="5"
+jobs:
+  exclude:
+    - python: "2.7"
+      env: ISORT_VER="5"
+    - python: "3.5"
+      env: ISORT_VER="5"
+    - python: "pypy"
+      env: ISORT_VER="5"
 cache: pip
 install:
+  - if [[ $ISORT_VER == "4" ]]; then pip install 'isort < 5'; fi
   - pip install .[test]
 script:
   - flake8 *.py
-  - pytest run_tests.py
+  - pytest -v
 after_success:
   - pip install -q -r requirements-cov.txt
-  - pytest run_tests.py --cov flake8_isort --cov-report term-missing
+  - pytest -v --cov flake8_isort --cov-report term-missing
   - coveralls

CHANGES.rst

@@ -3,10 +3,10 @@
 Changelog
 =========
 
-3.0.2 (unreleased)
+4.0.0 (unreleased)
 ------------------
 
-- Nothing changed yet.
+- support isort >= 5 [bnavigator, pkolbus]
 
 
 3.0.1 (2020-07-08)

flake8_isort.py

@@ -1,13 +1,23 @@
 # -*- coding: utf-8 -*-
-from difflib import Differ
-from isort import SortImports
-from testfixtures import OutputCapture
 
+import isort
 
-__version__ = '3.0.2.dev0'
 
+if hasattr(isort, 'api'):  # isort 5
+    from contextlib import redirect_stdout
+    from difflib import unified_diff
+    from io import StringIO
+    from pathlib import Path
 
-class Flake8Isort(object):
+    import warnings
+else:
+    from difflib import Differ
+    from testfixtures import OutputCapture
+
+__version__ = '4.0.0.dev0'
+
+
+class Flake8IsortBase(object):
     name = 'flake8_isort'
     version = __version__
     isort_unsorted = (
@@ -49,13 +59,17 @@ def parse_options(cls, options):
         cls.stdin_display_name = options.stdin_display_name
         cls.show_traceback = options.isort_show_traceback
 
+
+class Flake8Isort4(Flake8IsortBase):
+    """class for isort <5"""
+
     def run(self):
         if self.filename is not self.stdin_display_name:
             file_path = self.filename
         else:
             file_path = None
         with OutputCapture() as buffer:
-            sort_result = SortImports(
+            sort_result = isort.SortImports(
                 file_path=file_path,
                 file_contents=''.join(self.lines),
                 check=True,
@@ -168,3 +182,91 @@ def _fixup_sortimports_wrapped(sort_imports):
                 for new_idx, new_line in enumerate(
                         sort_imports.out_lines.pop(idx).splitlines()):
                     sort_imports.out_lines.insert(idx + new_idx, new_line)
+
+
+class Flake8Isort5(Flake8IsortBase):
+    """class for isort >=5"""
+
+    def run(self):
+        if self.filename is not self.stdin_display_name:
+            file_path = Path(self.filename)
+            isort_config = isort.settings.Config(
+                settings_path=file_path.parent)
+        else:
+            file_path = None
+            isort_config = isort.settings.Config(
+                settings_path=Path.cwd())
+        input_string = ''.join(self.lines)
+        traceback = ''
+        isort_changed = False
+        input_stream = StringIO(input_string)
+        output_stream = StringIO()
+        isort_stdout = StringIO()
+        try:
+            with redirect_stdout(isort_stdout):
+                isort_changed = isort.api.sort_stream(
+                    input_stream=input_stream,
+                    output_stream=output_stream,
+                    config=isort_config,
+                    file_path=file_path)
+        except isort.exceptions.FileSkipped:
+            pass
+        except isort.exceptions.ISortError as e:
+            warnings.warn(e)
+        if isort_changed:
+            outlines = output_stream.getvalue()
+            diff_delta = "".join(unified_diff(
+                              input_string.splitlines(keepends=True),
+                              outlines.splitlines(keepends=True),
+                              fromfile="{}:before".format(self.filename),
+                              tofile="{}:after".format(self.filename)))
+            traceback = (isort_stdout.getvalue() + "\n" + diff_delta)
+            for line_num, message in self.isort_linenum_msg(diff_delta):
+                if self.show_traceback:
+                    message += traceback
+                yield line_num, 0, message, type(self)
+
+    def isort_linenum_msg(self, udiff):
+        """Parse unified diff for changes and generate messages
+
+        Args
+        ----
+        udiff : unified diff delta
+
+        Yields
+        ------
+        tuple: A tuple of the specific isort line number and message.
+        """
+        line_num = 0
+        additions = []
+        moves = []
+        for line in udiff.splitlines():
+            if line.startswith('@@', 0, 2):
+                line_num = int(line[4:].split(' ')[0].split(',')[0])
+                continue
+            elif not line_num:  # skip lines before first hunk
+                continue
+            if line.startswith(' ', 0, 1):
+                line_num += 1  # Ignore unchanged lines but increment line_num.
+            elif line.startswith('-', 0, 1):
+                if line.strip() == '-':
+                    yield line_num, self.isort_blank_unexp
+                    line_num += 1
+                else:
+                    moves.append(line[1:])
+                    yield line_num, self.isort_unsorted
+                    line_num += 1
+            elif line.startswith('+', 0, 1):
+                if line.strip() == '+':
+                    # Include newline additions but do not increment line_num.
+                    yield line_num, self.isort_blank_req
+                else:
+                    additions.append((line_num, line))
+
+        # return all additions that did not move
+        for line_num, line in additions:
+            if not line[1:] in moves:
+                yield line_num, self.isort_add_unexp
+
+
+Flake8Isort = Flake8Isort5 if hasattr(isort, 'api') else Flake8Isort4