Fix CallInfo.__repr__ for unfinished call

Fixes pytest-dev#3554
Ref: pytest-dev#3560
Ref: pytest-dev#3562

Author: blueyed

changelog/3554.bugfix.rst

@@ -0,0 +1 @@
+Allow ``CallInfo`` to have an unfinished state represented by having a ``None`` value in the ``result`` attribute.

src/_pytest/runner.py

@@ -224,7 +224,8 @@ def __repr__(self):
         if self.excinfo:
             status = "exception: %s" % str(self.excinfo.value)
         else:
-            status = "result: %r" % (self.result,)
+            result = getattr(self, "result", "<NOTSET>")
+            status = "result: %r" % (result,)
         return "<CallInfo when=%r %s>" % (self.when, status)
 
 

testing/test_runner.py

@@ -493,11 +493,21 @@ def test_callinfo():
     assert "result" in repr(ci)
     ci = runner.CallInfo(lambda: 0 / 0, "123")
     assert ci.when == "123"
-    assert not hasattr(ci, "result")
+    assert ci.result is None
     assert ci.excinfo
     assert "exc" in repr(ci)
 
 
+def test_callinfo_repr_while_running():
+    def repr_while_running():
+        f = sys._getframe().f_back
+        assert "func" in f.f_locals
+        assert repr(f.f_locals["self"]) == "<CallInfo when='when' result: '<NOTSET>'>"
+
+    ci = runner.CallInfo(repr_while_running, "when")
+    assert repr(ci) == "<CallInfo when='when' result: None>"
+
+
 # design question: do we want general hooks in python files?
 # then something like the following functional tests makes sense