Fix linting issues

The unsubscriptable object errors are fixed in Pylint,
pylint-dev/pylint#2416, but the fixed release is
not available via prospector.

Author: pgjones

Diff for: .prospector.yml

@@ -1,6 +1,8 @@
 pylint:
   disable:
     - cyclic-import
+    - no-else-break
+    - no-else-continue
     - unused-argument
     - useless-object-inheritance
 

Diff for: compliance/run-autobahn-tests.py

@@ -203,7 +203,7 @@ def main() -> None:
         sys.exit(2)
     coverage_settings = {"coveragerc": "../.coveragerc"}
     try:
-        import wsproto
+        import wsproto  # pylint: disable=import-outside-toplevel
     except ImportError:
         say("wsproto must be on python path -- set PYTHONPATH or install it")
         sys.exit(2)

Diff for: tox.ini

@@ -40,9 +40,8 @@ commands =
 
 [testenv:lint]
 basepython = python3.6
-# pylint==2.1.1 required due to prospector bug, see https://github.com/PyCQA/prospector/pull/309
 deps =
-    prospector==1.1.7
+    prospector
 commands = prospector
 
 [testenv:docs]

Diff for: wsproto/events.py

@@ -222,7 +222,7 @@ class Message(Event, Generic[T]):
 
 
 @dataclass(frozen=True)
-class TextMessage(Message[str]):
+class TextMessage(Message[str]):  # pylint: disable=unsubscriptable-object
     """This event is fired when a data frame with TEXT payload is received.
 
     Fields:
@@ -240,7 +240,7 @@ class TextMessage(Message[str]):
 
 
 @dataclass(frozen=True)
-class BytesMessage(Message[bytes]):
+class BytesMessage(Message[bytes]):  # pylint: disable=unsubscriptable-object
     """This event is fired when a data frame with BINARY payload is
     received.