Make filesystem exceptions subclass from standard library exceptions

dissect/target/exceptions.py

@@ -73,15 +73,15 @@ class PluginNotFoundError(PluginError):
     """Plugin cannot be found."""
 
 
-class FileNotFoundError(FilesystemError):
+class FileNotFoundError(FilesystemError, FileNotFoundError):
     """The requested path could not be found."""
 
 
-class IsADirectoryError(FilesystemError):
+class IsADirectoryError(FilesystemError, IsADirectoryError):
     """The entry is a directory."""
 
 
-class NotADirectoryError(FilesystemError):
+class NotADirectoryError(FilesystemError, NotADirectoryError):
     """The entry is not a directory."""
 
 

tests/test_exceptions.py

@@ -0,0 +1,19 @@
+import pytest
+
+from dissect.target 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, exceptions.FilesystemError))
+    assert isinstance(exc(), (std, exceptions.FilesystemError))
+
+    with pytest.raises(std):
+        raise exc()