pprint empty flag combinations

https: //github.com//pull/3710#discussion_r1285467133
Co-Authored-By: Joachim B Haga <[email protected]>

Author: Zac-HD

hypothesis-python/RELEASE.rst

@@ -0,0 +1,4 @@
+RELEASE_TYPE: patch
+
+We can now pretty-print combinations of *zero* :class:`enum.Flag`
+values, like ``SomeFlag(0)``, which has never worked before.

hypothesis-python/src/hypothesis/vendor/pretty.py

@@ -804,7 +804,10 @@ def _repr_dataframe(obj, p, cycle):  # pragma: no cover
 def _repr_enum(obj, p, cycle):
     tname = type(obj).__name__
     if isinstance(obj, Flag):
-        p.text(" | ".join(f"{tname}.{x.name}" for x in type(obj) if x & obj == x))
+        p.text(
+            " | ".join(f"{tname}.{x.name}" for x in type(obj) if x & obj == x)
+            or f"{tname}({obj.value!r})"  # if no matching members
+        )
     else:
         p.text(f"{tname}.{obj.name}")
 

hypothesis-python/tests/cover/test_pretty.py

@@ -657,6 +657,7 @@ def __repr__(self):
         "Options.A",
         "Options.A | Options.B",
         "Options.A | Options.B | Options.C",
+        "Options(0)",
         "EvilReprOptions.A",
         "LyingReprOptions.A",
         "EvilReprOptions.A | EvilReprOptions.B",