Improve ExceptionInfo.__repr__ (#5934)

Improve ExceptionInfo.__repr__

Author: nicoddemus

doc/5934.feature.rst

@@ -0,0 +1 @@
+``repr`` of ``ExceptionInfo`` objects has been improved to honor the ``__repr__`` method of the underlying exception.

src/_pytest/_code/code.py

@@ -507,7 +507,9 @@ def traceback(self, value: Traceback) -> None:
     def __repr__(self) -> str:
         if self._excinfo is None:
             return "<ExceptionInfo for raises contextmanager>"
-        return "<ExceptionInfo %s tblen=%d>" % (self.typename, len(self.traceback))
+        return "<{} {} tblen={}>".format(
+            self.__class__.__name__, saferepr(self._excinfo[1]), len(self.traceback)
+        )
 
     def exconly(self, tryshort: bool = False) -> str:
         """ return the exception as a string

testing/code/test_excinfo.py

@@ -316,8 +316,19 @@ def test_excinfo_exconly():
 
 def test_excinfo_repr_str():
     excinfo = pytest.raises(ValueError, h)
-    assert repr(excinfo) == "<ExceptionInfo ValueError tblen=4>"
-    assert str(excinfo) == "<ExceptionInfo ValueError tblen=4>"
+    assert repr(excinfo) == "<ExceptionInfo ValueError() tblen=4>"
+    assert str(excinfo) == "<ExceptionInfo ValueError() tblen=4>"
+
+    class CustomException(Exception):
+        def __repr__(self):
+            return "custom_repr"
+
+    def raises():
+        raise CustomException()
+
+    excinfo = pytest.raises(CustomException, raises)
+    assert repr(excinfo) == "<ExceptionInfo custom_repr tblen=2>"
+    assert str(excinfo) == "<ExceptionInfo custom_repr tblen=2>"
 
 
 def test_excinfo_for_later():