4 files changed, 78 insertions, 34 deletions

diff --git a/lib/sqlalchemy/testing/__init__.py b/lib/sqlalchemy/testing/__init__.py
index 87208d3f4..fd6ddf593 100644
--- a/lib/sqlalchemy/testing/__init__.py
+++ b/lib/sqlalchemy/testing/__init__.py
@@ -12,6 +12,8 @@ from .assertions import assert_raises
 from .assertions import assert_raises_context_ok
 from .assertions import assert_raises_message
 from .assertions import assert_raises_message_context_ok
+from .assertions import assert_warns
+from .assertions import assert_warns_message
 from .assertions import AssertsCompiledSQL
 from .assertions import AssertsExecutionResults
 from .assertions import ComparesTables
diff --git a/lib/sqlalchemy/testing/assertions.py b/lib/sqlalchemy/testing/assertions.py
index f268b6fc3..2a00f1c14 100644
--- a/lib/sqlalchemy/testing/assertions.py
+++ b/lib/sqlalchemy/testing/assertions.py
@@ -139,13 +139,15 @@ def _expect_warnings(
     exc_cls,
     messages,
     regex=True,
+    search_msg=False,
     assert_=True,
     raise_on_any_unexpected=False,
+    squelch_other_warnings=False,
 ):
 
     global _FILTERS, _SEEN, _EXC_CLS
 
-    if regex:
+    if regex or search_msg:
         filters = [re.compile(msg, re.I | re.S) for msg in messages]
     else:
         filters = list(messages)
@@ -183,19 +185,23 @@ def _expect_warnings(
                 exception = None
 
             if not exception or not issubclass(exception, _EXC_CLS):
-                return real_warn(msg, *arg, **kw)
+                if not squelch_other_warnings:
+                    return real_warn(msg, *arg, **kw)
 
             if not filters and not raise_on_any_unexpected:
                 return
 
             for filter_ in filters:
-                if (regex and filter_.match(msg)) or (
-                    not regex and filter_ == msg
+                if (
+                    (search_msg and filter_.search(msg))
+                    or (regex and filter_.match(msg))
+                    or (not regex and filter_ == msg)
                 ):
                     seen.discard(filter_)
                     break
             else:
-                real_warn(msg, *arg, **kw)
+                if not squelch_other_warnings:
+                    real_warn(msg, *arg, **kw)
 
         with mock.patch("warnings.warn", our_warn):
             try:
@@ -343,6 +349,40 @@ def assert_raises_message(except_cls, msg, callable_, *args, **kwargs):
     )
 
 
+def assert_warns(except_cls, callable_, *args, **kwargs):
+    """legacy adapter function for functions that were previously using
+    assert_raises with SAWarning or similar.
+
+    has some workarounds to accommodate the fact that the callable completes
+    with this approach rather than stopping at the exception raise.
+
+
+    """
+    with _expect_warnings(except_cls, [".*"], squelch_other_warnings=True):
+        return callable_(*args, **kwargs)
+
+
+def assert_warns_message(except_cls, msg, callable_, *args, **kwargs):
+    """legacy adapter function for functions that were previously using
+    assert_raises with SAWarning or similar.
+
+    has some workarounds to accommodate the fact that the callable completes
+    with this approach rather than stopping at the exception raise.
+
+    Also uses regex.search() to match the given message to the error string
+    rather than regex.match().
+
+    """
+    with _expect_warnings(
+        except_cls,
+        [msg],
+        search_msg=True,
+        regex=False,
+        squelch_other_warnings=True,
+    ):
+        return callable_(*args, **kwargs)
+
+
 def assert_raises_message_context_ok(
     except_cls, msg, callable_, *args, **kwargs
 ):
@@ -364,6 +404,15 @@ class _ErrorContainer:
 
 @contextlib.contextmanager
 def _expect_raises(except_cls, msg=None, check_context=False):
+    if (
+        isinstance(except_cls, type)
+        and issubclass(except_cls, Warning)
+        or isinstance(except_cls, Warning)
+    ):
+        raise TypeError(
+            "Use expect_warnings for warnings, not "
+            "expect_raises / assert_raises"
+        )
     ec = _ErrorContainer()
     if check_context:
         are_we_already_in_a_traceback = sys.exc_info()[0]
diff --git a/lib/sqlalchemy/testing/plugin/pytestplugin.py b/lib/sqlalchemy/testing/plugin/pytestplugin.py
index 7a62ad008..2ae6730bb 100644
--- a/lib/sqlalchemy/testing/plugin/pytestplugin.py
+++ b/lib/sqlalchemy/testing/plugin/pytestplugin.py
@@ -13,16 +13,10 @@ import itertools
 import operator
 import os
 import re
+import uuid
 
 import pytest
 
-try:
-    import xdist  # noqa
-
-    has_xdist = True
-except ImportError:
-    has_xdist = False
-
 
 def pytest_addoption(parser):
     group = parser.getgroup("sqlalchemy")
@@ -75,6 +69,9 @@ def pytest_addoption(parser):
 
 
 def pytest_configure(config):
+    if config.pluginmanager.hasplugin("xdist"):
+        config.pluginmanager.register(XDistHooks())
+
     if hasattr(config, "workerinput"):
         plugin_base.restore_important_follower_config(config.workerinput)
         plugin_base.configure_follower(config.workerinput["follower_ident"])
@@ -148,10 +145,8 @@ def pytest_collection_finish(session):
         collect_types.init_types_collection(filter_filename=_filter)
 
 
-if has_xdist:
-    import uuid
-
-    def pytest_configure_node(node):
+class XDistHooks:
+    def pytest_configure_node(self, node):
         from sqlalchemy.testing import provision
         from sqlalchemy.testing import asyncio
 
@@ -166,7 +161,7 @@ if has_xdist:
             provision.create_follower_db, node.workerinput["follower_ident"]
         )
 
-    def pytest_testnodedown(node, error):
+    def pytest_testnodedown(self, node, error):
         from sqlalchemy.testing import provision
         from sqlalchemy.testing import asyncio
 
diff --git a/lib/sqlalchemy/testing/warnings.py b/lib/sqlalchemy/testing/warnings.py
index 34b23d675..1c2039602 100644
--- a/lib/sqlalchemy/testing/warnings.py
+++ b/lib/sqlalchemy/testing/warnings.py
@@ -11,8 +11,13 @@ from .. import exc as sa_exc
 from ..util.langhelpers import _warnings_warn
 
 
-class SATestSuiteWarning(sa_exc.SAWarning):
-    """warning for a condition detected during tests that is non-fatal"""
+class SATestSuiteWarning(Warning):
+    """warning for a condition detected during tests that is non-fatal
+
+    Currently outside of SAWarning so that we can work around tools like
+    Alembic doing the wrong thing with warnings.
+
+    """
 
 
 def warn_test_suite(message):
@@ -22,28 +27,21 @@ def warn_test_suite(message):
 def setup_filters():
     """Set global warning behavior for the test suite."""
 
+    # TODO: at this point we can use the normal pytest warnings plugin,
+    # if we decide the test suite can be linked to pytest only
+
+    origin = r"^(?:test|sqlalchemy)\..*"
+
     warnings.filterwarnings(
         "ignore", category=sa_exc.SAPendingDeprecationWarning
     )
     warnings.filterwarnings("error", category=sa_exc.SADeprecationWarning)
     warnings.filterwarnings("error", category=sa_exc.SAWarning)
-    warnings.filterwarnings("always", category=SATestSuiteWarning)
 
-    # some selected deprecations...
-    warnings.filterwarnings("error", category=DeprecationWarning)
-    warnings.filterwarnings(
-        "ignore", category=DeprecationWarning, message=r".*StopIteration"
-    )
-    warnings.filterwarnings(
-        "ignore",
-        category=DeprecationWarning,
-        message=r".*inspect.get.*argspec",
-    )
+    warnings.filterwarnings("always", category=SATestSuiteWarning)
 
     warnings.filterwarnings(
-        "ignore",
-        category=DeprecationWarning,
-        message="The loop argument is deprecated",
+        "error", category=DeprecationWarning, module=origin
     )
 
     try:
@@ -52,7 +50,7 @@ def setup_filters():
         pass
     else:
         warnings.filterwarnings(
-            "once", category=pytest.PytestDeprecationWarning
+            "once", category=pytest.PytestDeprecationWarning, module=origin
         )