Disallow .example(), add replacements

Author: jobh

hypothesis-python/tests/common/debug.py

@@ -89,16 +89,46 @@ def assert_no_examples(strategy, condition=lambda _: True):
         pass
 
 
-def assert_all_examples(strategy, predicate):
+def assert_all_examples(strategy, predicate, settings=None):
     """Asserts that all examples of the given strategy match the predicate.
 
     :param strategy: Hypothesis strategy to check
     :param predicate: (callable) Predicate that takes example and returns bool
     """
 
     @given(strategy)
+    @Settings(parent=settings)
     def assert_examples(s):
         msg = f"Found {s!r} using strategy {strategy} which does not match"
         assert predicate(s), msg
 
     assert_examples()
+
+
+def assert_simple_property(strategy, predicate, settings=None):
+    """Like assert_all_examples, intended as a self-documenting shortcut for simple constant
+    properties (`is`, `isinstance`, `==`, ...) that can be adequately verified in just a few
+    examples.
+
+    For more thorough checking, use assert_all_examples.
+    """
+
+    assert_all_examples(strategy, predicate, Settings(parent=settings, max_examples=15))
+
+
+def check_can_generate_examples(strategy, settings=None):
+    """Tries to generate a small number of examples from the strategy, to verify that it can
+      do so without raising.
+
+    Nothing is returned, it only checks that no error is raised.
+    """
+
+    assert_simple_property(
+        strategy,
+        lambda _: True,
+        settings=Settings(
+            parent=settings,
+            phases=(Phase.generate,),
+            suppress_health_check=list(HealthCheck),
+        ),
+    )

hypothesis-python/tests/common/setup.py

@@ -13,7 +13,6 @@
 
 from hypothesis import Phase, Verbosity, settings
 from hypothesis._settings import not_set
-from hypothesis.errors import NonInteractiveExampleWarning
 from hypothesis.internal.coverage import IN_COVERAGE_TESTS
 
 
@@ -36,9 +35,6 @@ def run():
         category=UserWarning,
     )
 
-    # User-facing warning which does not apply to our own tests
-    filterwarnings("ignore", category=NonInteractiveExampleWarning)
-
     # We do a smoke test here before we mess around with settings.
     x = settings()
 

pytest.ini

@@ -12,7 +12,6 @@ addopts =
 xfail_strict = True
 filterwarnings =
     error
-    ignore::hypothesis.errors.NonInteractiveExampleWarning
     # https://github.com/pandas-dev/pandas/issues/41199
     default:Creating a LegacyVersion has been deprecated and will be removed in the next major release:DeprecationWarning
     default:distutils Version classes are deprecated\. Use packaging\.version instead:DeprecationWarning