Protect against `NonDeducibleTypeHierarchy` when calling semi-private `is_subtype`

`astroid.helpers.is_subtype` raises `NonDeducibleTypeHierarchy` when it cannot infer
the base classes of the given types, but that makes sense in its context given that
the method is mostly used to inform the inference process about the hierarchy of classes.
Doesn't make that much sense for ``pylint`` itself, which is why we're handling the
exception here, rather than in ``astroid``

Close PyCQA/astroid#644

2 files changed, 26 insertions, 0 deletions

diff --git a/pylint/test/functional/try_except_raise_crash.py b/pylint/test/functional/try_except_raise_crash.py
new file mode 100644
index 000000000..7a1f8d972
--- /dev/null
+++ b/pylint/test/functional/try_except_raise_crash.py
@@ -0,0 +1,25 @@
+# pylint: disable=missing-docstring,too-many-ancestors, broad-except
+import collections.abc
+from typing import TYPE_CHECKING, Any, MutableMapping
+
+if TYPE_CHECKING:
+    BaseClass = MutableMapping[str, Any]
+else:
+    BaseClass = collections.abc.MutableMapping
+
+
+class TestBaseException(BaseClass):
+    pass
+
+
+class TestException(TestBaseException):
+    pass
+
+
+def test():
+    try:
+        1 / 0
+    except TestException:  # [try-except-raise]
+        raise
+    except Exception:
+        pass
diff --git a/pylint/test/functional/try_except_raise_crash.txt b/pylint/test/functional/try_except_raise_crash.txt
new file mode 100644
index 000000000..a99476ab9
--- /dev/null
+++ b/pylint/test/functional/try_except_raise_crash.txt
@@ -0,0 +1 @@
+try-except-raise:22:test:The except handler raises immediately