Keep galaxy.files off galaxy.managers

ProvidesFileSourcesUserContext took an untyped trans; annotating it as
ProvidesUserContext pointed galaxy.files at galaxy.managers, and the drs
test then imported that name at runtime for a cast. galaxy-files depends
on galaxy-util alone, so the package's own test run could not find
galaxy.managers and failed to collect.

Describe the transaction where it is used instead: the adapter reads user,
anonymous, user_is_admin, user_ftp_dir, user_vault and app, so state that
as a protocol in galaxy.files. Transactions satisfy it structurally, and
the test casts to something its package actually ships.

lib/galaxy/files/__init__.py

@@ -7,7 +7,6 @@ from typing import (
     Any,
     NamedTuple,
     Protocol,
-    TYPE_CHECKING,
 )
 
 from galaxy import exceptions
@@ -27,8 +26,28 @@ from .plugins import (
     FileSourcePluginsConfig,
 )
 
-if TYPE_CHECKING:
-    from galaxy.managers.context import ProvidesUserContext
+
+class ProvidesFileSourcesTransaction(Protocol):
+    """The slice of a Galaxy transaction ProvidesFileSourcesUserContext reads."""
+
+    @property
+    def anonymous(self) -> bool: ...
+
+    @property
+    def user(self) -> Any: ...
+
+    @property
+    def user_ftp_dir(self) -> str | None: ...
+
+    @property
+    def user_is_admin(self) -> bool: ...
+
+    @property
+    def user_vault(self) -> Any: ...
+
+    @property
+    def app(self) -> Any: ...
+
 
 log = logging.getLogger(__name__)
 
@@ -375,7 +394,7 @@ OptionalUserContext = FileSourcesUserContext | None
 class ProvidesFileSourcesUserContext(FileSourcesUserContext, FileSourceDictifiable):
     """Implement a FileSourcesUserContext from a Galaxy ProvidesUserContext (e.g. trans)."""
 
-    def __init__(self, trans: "ProvidesUserContext", **kwargs):
+    def __init__(self, trans: ProvidesFileSourcesTransaction, **kwargs):
         self.trans = trans
 
     @property

test/unit/files/test_drs.py

@@ -13,9 +13,9 @@ import responses
 
 from galaxy.files import (
     DictFileSourcesUserContext,
+    ProvidesFileSourcesTransaction,
     ProvidesFileSourcesUserContext,
 )
-from galaxy.managers.context import ProvidesUserContext
 from ._util import (
     assert_realizes_as,
     assert_realizes_contains,
@@ -46,7 +46,7 @@ def test_provides_file_sources_user_context_oidc_access_tokens():
     class DummyTrans:
         user = DummyUser()
 
-    tokens = ProvidesFileSourcesUserContext(cast(ProvidesUserContext, DummyTrans())).oidc_access_tokens
+    tokens = ProvidesFileSourcesUserContext(cast(ProvidesFileSourcesTransaction, DummyTrans())).oidc_access_tokens
     assert tokens == {"oidc": "oidc-token", "keycloak": "keycloak-token"}
 
 
@@ -56,7 +56,7 @@ def test_provides_file_sources_user_context_oidc_access_tokens_anonymous():
     class DummyTrans:
         user = None
 
-    assert ProvidesFileSourcesUserContext(cast(ProvidesUserContext, DummyTrans())).oidc_access_tokens is None
+    assert ProvidesFileSourcesUserContext(cast(ProvidesFileSourcesTransaction, DummyTrans())).oidc_access_tokens is None
 
 
 def test_drs_http_headers_template_expansion():