Merge "Remove internal use of string attr in loader option"

4 files changed, 87 insertions, 69 deletions

diff --git a/lib/sqlalchemy/orm/interfaces.py b/lib/sqlalchemy/orm/interfaces.py
index 7aae9ec37..a660d7e1a 100644
--- a/lib/sqlalchemy/orm/interfaces.py
+++ b/lib/sqlalchemy/orm/interfaces.py
@@ -83,6 +83,7 @@ class ORMFromClauseRole(roles.StrictFromClauseRole):
     _role_name = "ORM mapped entity, aliased entity, or FROM expression"
 
 
+@inspection._self_inspects
 class MapperProperty(
     HasCacheKey, _MappedAttribute, InspectionAttr, util.MemoizedSlots
 ):
diff --git a/lib/sqlalchemy/orm/strategies.py b/lib/sqlalchemy/orm/strategies.py
index 339a5bcf1..b11758090 100644
--- a/lib/sqlalchemy/orm/strategies.py
+++ b/lib/sqlalchemy/orm/strategies.py
@@ -992,7 +992,7 @@ class LazyLoader(AbstractRelationshipLoader, util.MemoizedSlots):
                         compile_context.compile_options._current_path[
                             rev.parent
                         ]
-                    ).lazyload(rev.key).process_compile_state(compile_context)
+                    ).lazyload(rev).process_compile_state(compile_context)
 
         stmt = stmt.add_criteria(
             lambda stmt: stmt._add_context_option(
diff --git a/lib/sqlalchemy/orm/strategy_options.py b/lib/sqlalchemy/orm/strategy_options.py
index 932c4a37d..ba4e5c466 100644
--- a/lib/sqlalchemy/orm/strategy_options.py
+++ b/lib/sqlalchemy/orm/strategy_options.py
@@ -234,84 +234,90 @@ class Load(Generative, LoaderOption):
                         raise
 
             path = path[attr]
-        elif _is_mapped_class(attr):
-            # TODO: this does not appear to be a valid codepath.  "attr"
-            # would never be a mapper.  This block is present in 1.2
-            # as well however does not seem to be accessed in any tests.
-            if not orm_util._entity_corresponds_to_use_path_impl(
-                attr.parent, path[-1]
-            ):
-                if raiseerr:
-                    raise sa_exc.ArgumentError(
-                        "Attribute '%s' does not "
-                        "link from element '%s'" % (attr, path.entity)
-                    )
-                else:
-                    return None
         else:
-            prop = found_property = attr.property
-
-            if not orm_util._entity_corresponds_to_use_path_impl(
-                attr.parent, path[-1]
-            ):
-                if raiseerr:
-                    raise sa_exc.ArgumentError(
-                        'Attribute "%s" does not '
-                        'link from element "%s".%s'
-                        % (
-                            attr,
-                            path.entity,
-                            (
-                                "  Did you mean to use "
-                                "%s.of_type(%s)?"
-                                % (path[-2], attr.class_.__name__)
-                                if len(path) > 1
-                                and path.entity.is_mapper
-                                and attr.parent.is_aliased_class
-                                else ""
-                            ),
+            insp = inspect(attr)
+
+            if insp.is_mapper or insp.is_aliased_class:
+                # TODO: this does not appear to be a valid codepath.  "attr"
+                # would never be a mapper.  This block is present in 1.2
+                # as well however does not seem to be accessed in any tests.
+                if not orm_util._entity_corresponds_to_use_path_impl(
+                    attr.parent, path[-1]
+                ):
+                    if raiseerr:
+                        raise sa_exc.ArgumentError(
+                            "Attribute '%s' does not "
+                            "link from element '%s'" % (attr, path.entity)
                         )
-                    )
-                else:
-                    return None
+                    else:
+                        return None
+            elif insp.is_property:
+                prop = found_property = attr
+                path = path[prop]
+            elif insp.is_attribute:
+                prop = found_property = attr.property
 
-            if attr._extra_criteria:
-                self._extra_criteria = attr._extra_criteria
+                if not orm_util._entity_corresponds_to_use_path_impl(
+                    attr.parent, path[-1]
+                ):
+                    if raiseerr:
+                        raise sa_exc.ArgumentError(
+                            'Attribute "%s" does not '
+                            'link from element "%s".%s'
+                            % (
+                                attr,
+                                path.entity,
+                                (
+                                    "  Did you mean to use "
+                                    "%s.of_type(%s)?"
+                                    % (path[-2], attr.class_.__name__)
+                                    if len(path) > 1
+                                    and path.entity.is_mapper
+                                    and attr.parent.is_aliased_class
+                                    else ""
+                                ),
+                            )
+                        )
+                    else:
+                        return None
 
-            if getattr(attr, "_of_type", None):
-                ac = attr._of_type
-                ext_info = of_type_info = inspect(ac)
+                if attr._extra_criteria:
+                    self._extra_criteria = attr._extra_criteria
 
-                if polymorphic_entity_context is None:
-                    polymorphic_entity_context = self.context
+                if getattr(attr, "_of_type", None):
+                    ac = attr._of_type
+                    ext_info = of_type_info = inspect(ac)
 
-                existing = path.entity_path[prop].get(
-                    polymorphic_entity_context, "path_with_polymorphic"
-                )
+                    if polymorphic_entity_context is None:
+                        polymorphic_entity_context = self.context
 
-                if not ext_info.is_aliased_class:
-                    ac = orm_util.with_polymorphic(
-                        ext_info.mapper.base_mapper,
-                        ext_info.mapper,
-                        aliased=True,
-                        _use_mapper_path=True,
-                        _existing_alias=inspect(existing)
-                        if existing is not None
-                        else None,
+                    existing = path.entity_path[prop].get(
+                        polymorphic_entity_context, "path_with_polymorphic"
                     )
 
-                    ext_info = inspect(ac)
+                    if not ext_info.is_aliased_class:
+                        ac = orm_util.with_polymorphic(
+                            ext_info.mapper.base_mapper,
+                            ext_info.mapper,
+                            aliased=True,
+                            _use_mapper_path=True,
+                            _existing_alias=inspect(existing)
+                            if existing is not None
+                            else None,
+                        )
 
-                path.entity_path[prop].set(
-                    polymorphic_entity_context, "path_with_polymorphic", ac
-                )
+                        ext_info = inspect(ac)
 
-                path = path[prop][ext_info]
+                    path.entity_path[prop].set(
+                        polymorphic_entity_context, "path_with_polymorphic", ac
+                    )
 
-                self._of_type = of_type_info
+                    path = path[prop][ext_info]
 
-            else:
-                path = path[prop]
+                    self._of_type = of_type_info
+
+                else:
+                    path = path[prop]
 
         if for_strategy is not None:
             found_property._get_strategy(for_strategy)
diff --git a/lib/sqlalchemy/testing/assertions.py b/lib/sqlalchemy/testing/assertions.py
index 289ac9a0a..02137474b 100644
--- a/lib/sqlalchemy/testing/assertions.py
+++ b/lib/sqlalchemy/testing/assertions.py
@@ -135,7 +135,12 @@ def uses_deprecated(*messages):
 
 @contextlib.contextmanager
 def _expect_warnings(
-    exc_cls, messages, regex=True, assert_=True, py2konly=False
+    exc_cls,
+    messages,
+    regex=True,
+    assert_=True,
+    py2konly=False,
+    raise_on_any_unexpected=False,
 ):
 
     if regex:
@@ -145,7 +150,13 @@ def _expect_warnings(
 
     seen = set(filters)
 
-    real_warn = warnings.warn
+    if raise_on_any_unexpected:
+
+        def real_warn(msg, *arg, **kw):
+            raise AssertionError("Got unexpected warning: %r" % msg)
+
+    else:
+        real_warn = warnings.warn
 
     def our_warn(msg, *arg, **kw):
         if isinstance(msg, exc_cls):
@@ -159,7 +170,7 @@ def _expect_warnings(
         if not exception or not issubclass(exception, exc_cls):
             return real_warn(msg, *arg, **kw)
 
-        if not filters:
+        if not filters and not raise_on_any_unexpected:
             return
 
         for filter_ in filters: