Add type annotations to pyreverse (#4551)

* Add type annotations to pyreverse dot files

Closes #1548

- Indicate the attribute is optional in the dot files by
  inspecting the default value.
- Handle the Subscript type annotations
- Refactor & move the logic to obtain annotations to utils.py as
  re-usable functions
- Add unittests for the added functions
- Add a try/except to deal with a possible InferenceError when using
NodeNG.infer method
- Create a function in utils and so remove repeated logic in inspector.py
- Add unittests to check the InferenceError logic
- Adjust the types in function input

1 files changed, 1 insertions, 1 deletions

diff --git a/pylint/pyreverse/diagrams.py b/pylint/pyreverse/diagrams.py
index bf9f67af6..4c391c7fa 100644
--- a/pylint/pyreverse/diagrams.py
+++ b/pylint/pyreverse/diagrams.py
@@ -122,7 +122,7 @@ class ClassDiagram(Figure, FilterMixIn):
             if isinstance(node, astroid.Instance):
                 node = node._proxied
             if (
-                isinstance(node, astroid.ClassDef)
+                isinstance(node, (astroid.ClassDef, astroid.Name, astroid.Subscript))
                 and hasattr(node, "name")
                 and not self.has_node(node)
             ):