Merge remote-tracking branch 'origin' into support-dataclass-transform

* origin:
  Fix pip install -e in docs
  Upgrade Mypy
  Fix a few flake8 issues
  Upgrade flake8
  Upgrade other test runners
  Remove 3.6/3.7 references and change tests slightly
  Upgrade OS's that it is tested on
  Try to add something to the README

test/run.py

@@ -134,7 +134,7 @@ TEST_GOTO = 2
 TEST_REFERENCES = 3
 
 
-grammar36 = parso.load_grammar(version='3.6')
+grammar313 = parso.load_grammar(version='3.13')
 
 
 class BaseTestCase(object):
@@ -238,7 +238,7 @@ class IntegrationTestCase(BaseTestCase):
             should_be = set()
             for match in re.finditer('(?:[^ ]+)', correct):
                 string = match.group(0)
-                parser = grammar36.parse(string, start_symbol='eval_input', error_recovery=False)
+                parser = grammar313.parse(string, start_symbol='eval_input', error_recovery=False)
                 parser_utils.move(parser.get_root_node(), self.line_nr)
                 node = parser.get_root_node()
                 module_context = script._get_module_context()
@@ -504,7 +504,7 @@ if __name__ == '__main__':
     if arguments['--env']:
         environment = get_system_environment(arguments['--env'])
     else:
-        # Will be 3.6.
+        # Will be 3.13.
         environment = get_default_environment()
 
     import traceback

test/test_api/test_environment.py

@@ -26,7 +26,7 @@ def test_find_system_environments():
 
 @pytest.mark.parametrize(
     'version',
-    ['3.6', '3.7', '3.8', '3.9']
+    ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13']
 )
 def test_versions(version):
     try:

test/test_inference/test_mixed.py

@@ -16,13 +16,13 @@ def test_on_code():
     assert i.infer()
 
 
-def test_generics_without_definition():
+def test_generics_without_definition() -> None:
     # Used to raise a recursion error
     T = TypeVar('T')
 
     class Stack(Generic[T]):
-        def __init__(self):
-            self.items = []  # type: List[T]
+        def __init__(self) -> None:
+            self.items: List[T] = []
 
         def push(self, item):
             self.items.append(item)

test/test_utils.py

@@ -91,7 +91,7 @@ class TestSetupReadline(unittest.TestCase):
         }
         # There are quite a few differences, because both Windows and Linux
         # (posix and nt) libraries are included.
-        assert len(difference) < 30
+        assert len(difference) < 40
 
     def test_local_import(self):
         s = 'import test.test_utils'