Support more kinds of mypy messages

Extracts a `format_message` to help unit testing

fix #339

.travis.yml

@@ -10,11 +10,10 @@ matrix:
   allow_failures:
     - python: "nightly"
 install:
-  - "pip install --editable .[build_tools]"
+  - "pip install --editable .[with_everything]"
 script:
   - "nosetests -s --with-coverage --cover-inclusive --cover-package=prospector tests/"
   - "mv .coverage .coverage.x"
-  - "pip install -e .[with_everything]"
   - "coverage run --parallel-mode prospector/run.py || true"
   - "coverage combine"
   - "coverage report --show-missing"

prospector/tools/mypy/__init__.py

@@ -1,11 +1,8 @@
 # -*- coding: utf-8 -*-
-from itertools import islice
 from mypy import api
-
 from prospector.message import Location, Message
 from prospector.tools import ToolBase
 
-
 __all__ = (
     'MypyTool',
 )
@@ -21,6 +18,28 @@
 ]
 
 
+def format_message(message):
+    try:
+        (path, line, char, err_type, err_msg) = message.split(':', 4)
+        character = int(char)
+    except ValueError:
+        (path, line, err_type, err_msg) = message.split(':', 3)
+        character = None
+    location = Location(
+        path=path,
+        module=None,
+        function=None,
+        line=int(line),
+        character=character,
+    )
+    return Message(
+        source='mypy',
+        code=err_type.lstrip(" "),
+        location=location,
+        message=err_msg.lstrip(" ")
+    )
+
+
 class MypyTool(ToolBase):
     def __init__(self, *args, **kwargs):
         super(MypyTool, self).__init__(*args, **kwargs)
@@ -72,25 +91,5 @@ def run(self, found_files):
         paths.extend(self.options)
         result = self.checker.run(paths)
         report, _ = result[0], result[1:]  # noqa
-        messages = []
-
-        for message in report.splitlines():
-            iter_message = iter(message.split(':'))
-            (path, line, char, err_type, err_msg) = islice(iter_message, 5)
-            location = Location(
-                path=path,
-                module=None,
-                function=None,
-                line=int(line),
-                character=int(char),
-                absolute_path=True
-            )
-            message = Message(
-                source='mypy',
-                code=err_type.lstrip(" "),
-                location=location,
-                message=err_msg.lstrip(" ")
-            )
-            messages.append(message)
-
-        return messages
+
+        return [format_message(message) for message in report.splitlines()]

tests/tools/mypy/test_mypy_tool.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+from unittest import TestCase
+
+from prospector.message import Location, Message
+from prospector.tools.mypy import format_message
+
+
+class TestMypyTool(TestCase):
+    def test_format_message_with_character(self):
+        location = Location(
+            path="file.py", module=None, function=None, line=17, character=2
+        )
+        expected = Message(
+            source="mypy", code="error", location=location, message="Important error"
+        )
+        self.assertEqual(
+            format_message("file.py:17:2: error: Important error"), expected
+        )
+
+    def test_format_message_without_character_and_columns_in_message(self):
+        location = Location(
+            path="file.py", module=None, function=None, line=17, character=None
+        )
+        expected = Message(
+            source="mypy", code="note", location=location, message="Important error"
+        )
+        self.assertEqual(
+            format_message('file.py:17: note: unused "type: ignore" comment'), expected
+        )
+
+    def test_format_message_without_character(self):
+        location = Location(
+            path="file.py", module=None, function=None, line=17, character=None
+        )
+        expected = Message(
+            source="mypy", code="error", location=location, message="Important error"
+        )
+        self.assertEqual(format_message("file.py:17: error: Important error"), expected)