Fix AttributeError in __repr__/__str__ for partially initialized objects (#118)

When objects fail during `__init__`, debuggers and exception handlers call `__repr__()` or `__str__()` on the partially constructed instance. These methods were accessing attributes not yet set, causing cascading `AttributeError` that obscured the original initialization error.

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: pavel-kirienko <3298404+pavel-kirienko@users.noreply.github.com>
Co-authored-by: Pavel Kirienko <pavel.kirienko@gmail.com>

Author: Copilot

README.md

@@ -1,7 +1,6 @@
 # PyDSDL
 
-[![Build status](https://ci.appveyor.com/api/projects/status/lurx5gihhcl9wq1w/branch/master?svg=true)](https://ci.appveyor.com/project/Zubax/pydsdl/branch/master)
-[![Documentation Status](https://readthedocs.org/projects/pydsdl/badge/?version=latest)](https://pydsdl.readthedocs.io/en/latest/?badge=latest)
+[![Documentation](https://readthedocs.org/projects/pydsdl/badge/?version=latest)](https://pydsdl.readthedocs.io/en/latest/?badge=latest)
 [![PyPI - Downloads](https://img.shields.io/pypi/dm/pydsdl)](https://pypi.org/project/pydsdl/)
 [![Forum](https://img.shields.io/discourse/https/forum.opencyphal.org/users.svg)](https://forum.opencyphal.org)
 

pydsdl/__init__.py

@@ -7,7 +7,7 @@
 import sys as _sys
 from pathlib import Path as _Path
 
-__version__ = "1.24.2"
+__version__ = "1.24.3"
 __version_info__ = tuple(map(int, __version__.split(".")[:3]))
 __license__ = "MIT"
 __author__ = "OpenCyphal"

pydsdl/_expression/_any.py

@@ -54,7 +54,10 @@ def __str__(self) -> str:
         raise NotImplementedError  # pragma: no cover
 
     def __repr__(self) -> str:
-        return self.TYPE_NAME + "(" + str(self) + ")"
+        try:
+            return self.TYPE_NAME + "(" + str(self) + ")"
+        except (AttributeError, NotImplementedError):  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
     # Unary operators.
     def _logical_not(self) -> "Boolean":

pydsdl/_expression/_container.py

@@ -83,7 +83,10 @@ def __eq__(self, other: object) -> bool:
         return NotImplemented
 
     def __str__(self) -> str:
-        return "{%s}" % ", ".join(map(str, self._value))  # This is recursive.
+        try:
+            return "{%s}" % ", ".join(map(str, self._value))  # This is recursive.
+        except (AttributeError, TypeError):  # pragma: no cover
+            return "Set(UNINITIALIZED)"
 
     #
     # Set algebra implementation.

pydsdl/_expression/_primitive.py

@@ -47,7 +47,10 @@ def __eq__(self, other: object) -> bool:
         return NotImplemented  # pragma: no cover
 
     def __str__(self) -> str:
-        return "true" if self._value else "false"
+        try:
+            return "true" if self._value else "false"
+        except AttributeError:  # pragma: no cover
+            return "Boolean(UNINITIALIZED)"
 
     def __bool__(self) -> bool:  # For use in expressions without accessing "native_value"
         return self._value
@@ -107,7 +110,10 @@ def __eq__(self, other: object) -> bool:
         return NotImplemented  # pragma: no cover
 
     def __str__(self) -> str:
-        return str(self._value)
+        try:
+            return str(self._value)
+        except AttributeError:  # pragma: no cover
+            return "Rational(UNINITIALIZED)"
 
     #
     # Unary operators.
@@ -216,7 +222,10 @@ def __eq__(self, other: object) -> bool:
         return NotImplemented  # pragma: no cover
 
     def __str__(self) -> str:
-        return repr(self._value)
+        try:
+            return repr(self._value)
+        except AttributeError:  # pragma: no cover
+            return "String(UNINITIALIZED)"
 
     def _add(self, right: _any.Any) -> "String":
         if isinstance(right, String):

pydsdl/_serializable/_array.py

@@ -98,10 +98,16 @@ def enumerate_elements_with_offsets(
             yield index, offset
 
     def __str__(self) -> str:
-        return "%s[%d]" % (self.element_type, self.capacity)
+        try:
+            return "%s[%d]" % (self.element_type, self.capacity)
+        except AttributeError:  # pragma: no cover
+            return "FixedLengthArrayType(UNINITIALIZED)"
 
     def __repr__(self) -> str:
-        return "FixedLengthArrayType(element_type=%r, capacity=%r)" % (self.element_type, self.capacity)
+        try:
+            return "FixedLengthArrayType(element_type=%r, capacity=%r)" % (self.element_type, self.capacity)
+        except AttributeError:  # pragma: no cover
+            return "FixedLengthArrayType(UNINITIALIZED)"
 
 
 def _unittest_fixed_array() -> None:
@@ -178,10 +184,16 @@ def length_field_type(self) -> UnsignedIntegerType:
         return self._length_field_type
 
     def __str__(self) -> str:
-        return "%s[<=%d]" % (self.element_type, self.capacity)
+        try:
+            return "%s[<=%d]" % (self.element_type, self.capacity)
+        except AttributeError:  # pragma: no cover
+            return "VariableLengthArrayType(UNINITIALIZED)"
 
     def __repr__(self) -> str:
-        return "VariableLengthArrayType(element_type=%r, capacity=%r)" % (self.element_type, self.capacity)
+        try:
+            return "VariableLengthArrayType(element_type=%r, capacity=%r)" % (self.element_type, self.capacity)
+        except AttributeError:  # pragma: no cover
+            return "VariableLengthArrayType(UNINITIALIZED)"
 
 
 def _unittest_variable_array() -> None:

pydsdl/_serializable/_attribute.py

@@ -53,10 +53,16 @@ def __eq__(self, other: object) -> bool:
 
     def __str__(self) -> str:
         """Returns the normalized DSDL representation of the attribute."""
-        return ("%s %s" % (self.data_type, self.name)).strip()
+        try:
+            return ("%s %s" % (self.data_type, self.name)).strip()
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
     def __repr__(self) -> str:
-        return "%s(data_type=%r, name=%r)" % (self.__class__.__name__, self.data_type, self.name)
+        try:
+            return "%s(data_type=%r, name=%r)" % (self.__class__.__name__, self.data_type, self.name)
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
 
 class Field(Attribute):
@@ -145,10 +151,16 @@ def __eq__(self, other: object) -> bool:
 
     def __str__(self) -> str:
         """Returns the normalized DSDL representation of the constant and its value."""
-        return "%s %s = %s" % (self.data_type, self.name, self.value)
+        try:
+            return "%s %s = %s" % (self.data_type, self.name, self.value)
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
     def __repr__(self) -> str:
-        return "Constant(data_type=%r, name=%r, value=%r)" % (self.data_type, self.name, self._value)
+        try:
+            return "Constant(data_type=%r, name=%r, value=%r)" % (self.data_type, self.name, self._value)
+        except AttributeError:  # pragma: no cover
+            return "Constant(UNINITIALIZED)"
 
 
 def _unittest_attribute() -> None:

pydsdl/_serializable/_composite.py

@@ -353,22 +353,28 @@ def __getitem__(self, attribute_name: str) -> Attribute:
 
     def __str__(self) -> str:
         """Returns a string like ``uavcan.node.Heartbeat.1.0``."""
-        return "%s.%d.%d" % (self.full_name, self.version.major, self.version.minor)
+        try:
+            return "%s.%d.%d" % (self.full_name, self.version.major, self.version.minor)
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
     def __repr__(self) -> str:
-        return (
-            "%s(name=%r, version=%r, fields=%r, constants=%r, alignment_requirement=%r, "
-            "deprecated=%r, fixed_port_id=%r)"
-        ) % (
-            self.__class__.__name__,
-            self.full_name,
-            self.version,
-            self.fields,
-            self.constants,
-            self.alignment_requirement,
-            self.deprecated,
-            self.fixed_port_id,
-        )
+        try:
+            return (
+                "%s(name=%r, version=%r, fields=%r, constants=%r, alignment_requirement=%r, "
+                "deprecated=%r, fixed_port_id=%r)"
+            ) % (
+                self.__class__.__name__,
+                self.full_name,
+                self.version,
+                self.fields,
+                self.constants,
+                self.alignment_requirement,
+                self.deprecated,
+                self.fixed_port_id,
+            )
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
 
 class UnionType(CompositeType):
@@ -651,7 +657,10 @@ def _check_aggregation(self, aggregate: "SerializableType") -> typing.Optional[A
         return super()._check_aggregation(aggregate)
 
     def __repr__(self) -> str:
-        return "%s(inner=%r, extent=%r)" % (self.__class__.__name__, self.inner_type, self.extent)
+        try:
+            return "%s(inner=%r, extent=%r)" % (self.__class__.__name__, self.inner_type, self.extent)
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
 
 class ServiceType(CompositeType):

pydsdl/_serializable/_primitive.py

@@ -100,7 +100,10 @@ def __str__(self) -> str:  # pragma: no cover
         raise NotImplementedError
 
     def __repr__(self) -> str:
-        return "%s(bit_length=%r, cast_mode=%r)" % (self.__class__.__name__, self.bit_length, self.cast_mode)
+        try:
+            return "%s(bit_length=%r, cast_mode=%r)" % (self.__class__.__name__, self.bit_length, self.cast_mode)
+        except AttributeError:  # pragma: no cover
+            return "%s(UNINITIALIZED)" % self.__class__.__name__
 
 
 class BooleanType(PrimitiveType):

pydsdl/_serializable/_void.py

@@ -50,10 +50,16 @@ def alignment_requirement(self) -> int:
         return 1
 
     def __str__(self) -> str:
-        return "void%d" % self.bit_length
+        try:
+            return "void%d" % self.bit_length
+        except AttributeError:  # pragma: no cover
+            return "VoidType(UNINITIALIZED)"
 
     def __repr__(self) -> str:
-        return "VoidType(bit_length=%d)" % self.bit_length
+        try:
+            return "VoidType(bit_length=%d)" % self.bit_length
+        except AttributeError:  # pragma: no cover
+            return "VoidType(UNINITIALIZED)"
 
 
 def _unittest_void() -> None: