From fe4bbda511384d591d128de60c47e8ec8c101343 Mon Sep 17 00:00:00 2001
From: Erik Schamper <1254028+Schamper@users.noreply.github.com>
Date: Fri, 1 Nov 2024 14:58:14 +0100
Subject: [PATCH] Subclass exceptions from standard library exceptions (#18)

---
 dissect/btrfs/exceptions.py |  6 +++---
 tests/test_exceptions.py    | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 tests/test_exceptions.py

diff --git a/dissect/btrfs/exceptions.py b/dissect/btrfs/exceptions.py
index fe8e760..1b34e2c 100644
--- a/dissect/btrfs/exceptions.py
+++ b/dissect/btrfs/exceptions.py
@@ -2,15 +2,15 @@ class Error(Exception):
     pass
 
 
-class FileNotFoundError(Error):
+class FileNotFoundError(Error, FileNotFoundError):
     pass
 
 
-class NotAFileError(Error):
+class IsADirectoryError(Error, IsADirectoryError):
     pass
 
 
-class NotADirectoryError(Error):
+class NotADirectoryError(Error, NotADirectoryError):
     pass
 
 
diff --git a/tests/test_exceptions.py b/tests/test_exceptions.py
new file mode 100644
index 0000000..c8eed63
--- /dev/null
+++ b/tests/test_exceptions.py
@@ -0,0 +1,19 @@
+import pytest
+
+from dissect.btrfs import exceptions
+
+
+@pytest.mark.parametrize(
+    "exc, std",
+    [
+        (exceptions.FileNotFoundError, FileNotFoundError),
+        (exceptions.IsADirectoryError, IsADirectoryError),
+        (exceptions.NotADirectoryError, NotADirectoryError),
+    ],
+)
+def test_filesystem_error_subclass(exc: exceptions.Error, std: Exception) -> None:
+    assert issubclass(exc, std)
+    assert isinstance(exc(), std)
+
+    with pytest.raises(std):
+        raise exc()