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koubaafilmor
koubaa
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filmor
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Provide hook to implement __repr__ (#808)
Provide hook to implement __repr__
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9 files changed

+244
-6
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9 files changed

+244
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lines changed

‎AUTHORS.md

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@@ -41,6 +41,7 @@
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- Luke Stratman ([@lstratman](https://github.com/lstratman))
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- Konstantin Posudevskiy ([@konstantin-posudevskiy](https://github.com/konstantin-posudevskiy))
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- Matthias Dittrich ([@matthid](https://github.com/matthid))
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- Mohamed Koubaa ([@koubaa](https://github.com/koubaa))
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- Patrick Stewart ([@patstew](https://github.com/patstew))
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- Raphael Nestler ([@rnestler](https://github.com/rnestler))
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- Rickard Holmberg ([@rickardraysearch](https://github.com/rickardraysearch))

‎CHANGELOG.md

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@@ -46,6 +46,7 @@ This document follows the conventions laid out in [Keep a CHANGELOG][].
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- Added PyObject finalizer support, Python objects referred by C# can be auto collect now ([#692][p692]).
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- Added detailed comments about aproaches and dangers to handle multi-app-domains ([#625][p625])
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- Python 3.7 support, builds and testing added. Defaults changed from Python 3.6 to 3.7 ([#698][p698])
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- Added support for C# types to provide `__repr__` ([#680][p680])
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### Changed
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‎src/runtime/classbase.cs

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@@ -246,6 +246,44 @@ public static IntPtr tp_str(IntPtr ob)
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}
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}
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public static IntPtr tp_repr(IntPtr ob)
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{
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var co = GetManagedObject(ob) as CLRObject;
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if (co == null)
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{
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return Exceptions.RaiseTypeError("invalid object");
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}
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try
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{
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//if __repr__ is defined, use it
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var instType = co.inst.GetType();
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System.Reflection.MethodInfo methodInfo = instType.GetMethod("__repr__");
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if (methodInfo != null && methodInfo.IsPublic)
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{
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var reprString = methodInfo.Invoke(co.inst, null) as string;
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return Runtime.PyString_FromString(reprString);
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}
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//otherwise use the standard object.__repr__(inst)
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IntPtr args = Runtime.PyTuple_New(1);
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Runtime.PyTuple_SetItem(args, 0, ob);
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IntPtr reprFunc = Runtime.PyObject_GetAttrString(Runtime.PyBaseObjectType, "__repr__");
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var output = Runtime.PyObject_Call(reprFunc, args, IntPtr.Zero);
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Runtime.XDecref(args);
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Runtime.XDecref(reprFunc);
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return output;
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}
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catch (Exception e)
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{
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if (e.InnerException != null)
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{
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e = e.InnerException;
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}
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Exceptions.SetError(e);
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return IntPtr.Zero;
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}
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}
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249287

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/// <summary>
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/// Standard dealloc implementation for instances of reflected types.

‎src/runtime/exceptions.cs

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@@ -36,6 +36,29 @@ internal static Exception ToException(IntPtr ob)
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return e;
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}
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/// <summary>
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/// Exception __repr__ implementation
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/// </summary>
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public new static IntPtr tp_repr(IntPtr ob)
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{
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Exception e = ToException(ob);
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if (e == null)
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{
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return Exceptions.RaiseTypeError("invalid object");
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}
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string name = e.GetType().Name;
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string message;
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if (e.Message != String.Empty)
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{
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message = String.Format("{0}('{1}')", name, e.Message);
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}
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else
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{
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message = String.Format("{0}()", name);
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}
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return Runtime.PyUnicode_FromString(message);
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}
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/// <summary>
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/// Exception __str__ implementation
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/// </summary>

‎src/testing/Python.Test.csproj

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@@ -91,6 +91,7 @@
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<Compile Include="threadtest.cs" />
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<Compile Include="doctest.cs" />
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<Compile Include="subclasstest.cs" />
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<Compile Include="ReprTest.cs" />
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</ItemGroup>
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<ItemGroup>
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<Reference Include="Microsoft.CSharp" />
@@ -111,4 +112,4 @@
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<Copy SourceFiles="$(TargetAssembly)" DestinationFolder="$(SolutionDir)\src\tests\fixtures" />
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<!--Copy SourceFiles="$(TargetAssemblyPdb)" Condition="Exists('$(TargetAssemblyPdb)')" DestinationFolder="$(PythonBuildDir)" /-->
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</Target>
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</Project>
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</Project>

‎src/testing/ReprTest.cs

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@@ -0,0 +1,108 @@
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using System;
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using System.Text;
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namespace Python.Test
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{
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/// <summary>
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/// Supports repr unit tests.
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/// </summary>
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public class ReprTest
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{
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public class Point
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{
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public Point(double x, double y)
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{
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X = x;
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Y = y;
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}
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public double X { get; set; }
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public double Y { get; set; }
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public override string ToString()
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{
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return base.ToString() + ": X=" + X.ToString() + ", Y=" + Y.ToString();
25+
}
26+
27+
public string __repr__()
28+
{
29+
return "Point(" + X.ToString() + "," + Y.ToString() + ")";
30+
}
31+
}
32+
33+
public class Foo
34+
{
35+
public string __repr__()
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{
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return "I implement __repr__() but not ToString()!";
38+
}
39+
}
40+
41+
public class Bar
42+
{
43+
public override string ToString()
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{
45+
return "I implement ToString() but not __repr__()!";
46+
}
47+
}
48+
49+
public class BazBase
50+
{
51+
public override string ToString()
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{
53+
return "Base class implementing ToString()!";
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}
55+
}
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57+
public class BazMiddle : BazBase
58+
{
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public override string ToString()
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{
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return "Middle class implementing ToString()!";
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}
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}
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//implements ToString via BazMiddle
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public class Baz : BazMiddle
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{
68+
69+
}
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public class Quux
72+
{
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public string ToString(string format)
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{
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return "I implement ToString() with an argument!";
76+
}
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}
78+
79+
public class QuuzBase
80+
{
81+
protected string __repr__()
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{
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return "I implement __repr__ but it isn't public!";
84+
}
85+
}
86+
87+
public class Quuz : QuuzBase
88+
{
89+
90+
}
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92+
public class Corge
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{
94+
public string __repr__(int i)
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{
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return "__repr__ implemention with input parameter!";
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}
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}
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public class Grault
101+
{
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public int __repr__()
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{
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return "__repr__ implemention with wrong return type!".Length;
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}
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}
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}
108+
}

‎src/tests/test_exceptions.py

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@@ -282,11 +282,8 @@ def test_python_compat_of_managed_exceptions():
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283283
assert e.args == (msg,)
284284
assert isinstance(e.args, tuple)
285-
if PY3:
286-
strexp = "OverflowException('Simple message"
287-
assert repr(e)[:len(strexp)] == strexp
288-
elif PY2:
289-
assert repr(e) == "OverflowException(u'Simple message',)"
285+
strexp = "OverflowException('Simple message"
286+
assert repr(e)[:len(strexp)] == strexp
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292289
def test_exception_is_instance_of_system_object():

‎src/tests/test_repr.py

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@@ -0,0 +1,68 @@
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# -*- coding: utf-8 -*-
2+
3+
"""Test __repr__ output"""
4+
5+
import System
6+
import pytest
7+
from Python.Test import ReprTest
8+
9+
def test_basic():
10+
"""Test Point class which implements both ToString and __repr__ without inheritance"""
11+
ob = ReprTest.Point(1,2)
12+
# point implements ToString() and __repr__()
13+
assert ob.__repr__() == "Point(1,2)"
14+
assert str(ob) == "Python.Test.ReprTest+Point: X=1, Y=2"
15+
16+
def test_system_string():
17+
"""Test system string"""
18+
ob = System.String("hello")
19+
assert str(ob) == "hello"
20+
assert "<System.String object at " in ob.__repr__()
21+
22+
def test_str_only():
23+
"""Test class implementing ToString() but not __repr__()"""
24+
ob = ReprTest.Bar()
25+
assert str(ob) == "I implement ToString() but not __repr__()!"
26+
assert "<Python.Test.Bar object at " in ob.__repr__()
27+
28+
def test_hierarchy1():
29+
"""Test inheritance heirarchy with base & middle class implementing ToString"""
30+
ob1 = ReprTest.BazBase()
31+
assert str(ob1) == "Base class implementing ToString()!"
32+
assert "<Python.Test.BazBase object at " in ob1.__repr__()
33+
34+
ob2 = ReprTest.BazMiddle()
35+
assert str(ob2) == "Middle class implementing ToString()!"
36+
assert "<Python.Test.BazMiddle object at " in ob2.__repr__()
37+
38+
ob3 = ReprTest.Baz()
39+
assert str(ob3) == "Middle class implementing ToString()!"
40+
assert "<Python.Test.Baz object at " in ob3.__repr__()
41+
42+
def bad_tostring():
43+
"""Test ToString that can't be used by str()"""
44+
ob = ReprTest.Quux()
45+
assert str(ob) == "Python.Test.ReprTest+Quux"
46+
assert "<Python.Test.Quux object at " in ob.__repr__()
47+
48+
def bad_repr():
49+
"""Test incorrect implementation of repr"""
50+
ob1 = ReprTest.QuuzBase()
51+
assert str(ob1) == "Python.Test.ReprTest+QuuzBase"
52+
assert "<Python.Test.QuuzBase object at " in ob.__repr__()
53+
54+
ob2 = ReprTest.Quuz()
55+
assert str(ob2) == "Python.Test.ReprTest+Quuz"
56+
assert "<Python.Test.Quuz object at " in ob.__repr__()
57+
58+
ob3 = ReprTest.Corge()
59+
with pytest.raises(Exception):
60+
str(ob3)
61+
with pytest.raises(Exception):
62+
ob3.__repr__()
63+
64+
ob4 = ReprTest.Grault()
65+
with pytest.raises(Exception):
66+
str(ob4)
67+
with pytest.raises(Exception):
68+
ob4.__repr__()

‎src/tests/tests.pyproj

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@@ -59,6 +59,7 @@
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<Compile Include="test_recursive_types.py" />
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<Compile Include="test_subclass.py" />
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<Compile Include="test_thread.py" />
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<Compile Include="test_repr.py" />
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<Compile Include="utils.py" />
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<Compile Include="fixtures\argv-fixture.py" />
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</ItemGroup>

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