From 05180e80e75073a4e1d76e4ace588482a7d4fbb8 Mon Sep 17 00:00:00 2001
From: Eric Wolf <robo-eric@gmx.de>
Date: Sun, 4 Sep 2022 05:59:35 +0200
Subject: [PATCH] improve CollisionError string representations

---
 lambda_calculus/__init__.py |  2 +-
 lambda_calculus/errors.py   |  7 +++++--
 pyproject.toml              |  2 +-
 tests/test_errors.py        | 35 +++++++++++++++++++++++++++++++++++
 4 files changed, 42 insertions(+), 4 deletions(-)
 create mode 100644 tests/test_errors.py

diff --git a/lambda_calculus/__init__.py b/lambda_calculus/__init__.py
index 52fab47..ba61366 100644
--- a/lambda_calculus/__init__.py
+++ b/lambda_calculus/__init__.py
@@ -4,7 +4,7 @@
 
 from .terms import Variable, Abstraction, Application
 
-__version__ = "2.0.0"
+__version__ = "2.0.1"
 __author__  = "Eric Niklas Wolf"
 __email__   = "eric_niklas.wolf@mailbox.tu-dresden.de"
 __all__ = (
diff --git a/lambda_calculus/errors.py b/lambda_calculus/errors.py
index 3866c07..0f43300 100644
--- a/lambda_calculus/errors.py
+++ b/lambda_calculus/errors.py
@@ -28,8 +28,11 @@ def __init__(self, message: str, collisions: Collection[V]) -> None:
         self.collisions = collisions
 
     def __repr__(self) -> str:
-        return f"{self.__class__.__name__}({self.message!r}, {self.collisions!r})"
+        return (
+            f"{self.__class__.__module__}.{self.__class__.__qualname__}"
+            f"({self.message!r}, {self.collisions!r})"
+        )
 
     def __str__(self) -> str:
         collisions = ", ".join(map(str, self.collisions))
-        return f"[collisions: {collisions}] {self.message}"
+        return f"[collisions: {collisions or 'none'}] {self.message}"
diff --git a/pyproject.toml b/pyproject.toml
index 3f90e65..3a9de30 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "lambda_calculus"
-version = "2.0.0"
+version = "2.0.1"
 description = "Implementation of the Lambda calculus"
 requires-python = ">=3.10"
 keywords = []
diff --git a/tests/test_errors.py b/tests/test_errors.py
new file mode 100644
index 0000000..6da2bbe
--- /dev/null
+++ b/tests/test_errors.py
@@ -0,0 +1,35 @@
+#!/usr/bin/python3
+
+"""Tests for custom errors"""
+
+from unittest import TestCase
+from lambda_calculus import errors
+
+
+class CollisionErrorTest(TestCase):
+    """Tests for Exception thrown when a variable already exists"""
+
+    def test_exception(self) -> None:
+        """test exception subclass"""
+        exception: Exception = errors.CollisionError("test", [])
+        self.assertIsInstance(exception, ValueError)
+        self.assertEqual(exception.args, ("test", []))
+
+    def test_repr(self) -> None:
+        """test string representation"""
+        exception: Exception = errors.CollisionError("test", [])
+        self.assertEqual(
+            repr(exception),
+            f"lambda_calculus.errors.CollisionError({'test'!r}, {[]!r})"
+        )
+
+    def test_str(self) -> None:
+        """test exception message"""
+        self.assertEqual(
+            str(errors.CollisionError("test", [])),
+            "[collisions: none] test"
+        )
+        self.assertEqual(
+            str(errors.CollisionError("test", range(3))),
+            "[collisions: 0, 1, 2] test"
+        )