Improve mypy handling a little bit more

test/test_find_nearest_directory.vader

@@ -0,0 +1,15 @@
+Execute(Open a file some directory down):
+  silent! cd /testplugin/test
+  :e! top/middle/bottom/dummy.txt
+
+Then(We should be able to find the right directory):
+  AssertEqual
+  \ expand('%:p:h:h:h:h') . '/top/ale-special-directory-name-dont-use-this-please/',
+  \ ale#util#FindNearestDirectory(bufnr('%'), 'ale-special-directory-name-dont-use-this-please')
+
+Execute(Do nothing):
+
+Then(We shouldn't find anything for files which don't match):
+  AssertEqual
+  \ '',
+  \ ale#util#FindNearestDirectory(bufnr('%'), 'ale-this-should-never-match-anything')

test/test_mypy_handler.vader

@@ -0,0 +1,22 @@
+Execute(The mypy handler should parse lines correctly):
+  runtime ale_linters/python/mypy.vim
+
+  AssertEqual
+  \ [
+  \   {
+  \     'bufnr': 347,
+  \     'lnum': 4,
+  \     'vcol': 0,
+  \     'col': 0,
+  \     'text': "No library stub file for module 'django.db'",
+  \     'type': 'E',
+  \     'nr': -1,
+  \   },
+  \ ],
+  \ ale_linters#python#mypy#Handle(347, [
+  \   "file.py:4: error: No library stub file for module 'django.db'",
+  \   'file.py:4: note: (Stub files are from https://github.com/python/typeshed)',
+  \ ])
+
+After:
+  call ale#linter#Reset()

test/test_resolve_local_path.vader

@@ -2,7 +2,7 @@ Execute(Open a file some directory down):
   silent! cd /testplugin/test
   :e! top/middle/bottom/dummy.txt
 
-Then(We should be able to to find the local version of a file):
+Then(We should be able to find the local version of a file):
   AssertEqual
   \ expand('%:p:h:h:h:h') . '/top/example.ini',
   \  ale#util#ResolveLocalPath(bufnr('%'), 'example.ini', '/global/config.ini')