Remove deprecated add_hidden_timestamp feature and dead code

- Remove add_hidden_timestamp config setting (replaced by job metadata)
- Remove hash-based timestamp column generation from declare.py
- Remove unused sha1 import
- Remove unused test fixtures: monkeysession, monkeymodule, enable_adapted_types
- Clean up empty Utility Fixtures section in conftest.py

Job metadata feature (config.jobs.add_job_metadata) remains for computed
table provenance tracking.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: dimitri-yatsenko

src/datajoint/declare.py

@@ -5,7 +5,6 @@
 
 import logging
 import re
-from hashlib import sha1
 
 import pyparsing as pp
 
@@ -297,13 +296,6 @@ def declare(full_table_name, definition, context):
         fk_attribute_map,
     ) = prepare_declare(definition, context)
 
-    if config.get("add_hidden_timestamp", False):
-        metadata_attr_sql = ["`_{full_table_name}_timestamp` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP"]
-        attribute_sql.extend(
-            attr.format(full_table_name=sha1(full_table_name.replace("`", "").encode("utf-8")).hexdigest())
-            for attr in metadata_attr_sql
-        )
-
     # Add hidden job metadata for Computed/Imported tables (not parts)
     # Note: table_name may still have backticks, strip them for prefix checking
     clean_table_name = table_name.strip("`")

src/datajoint/settings.py

@@ -302,7 +302,6 @@ class Config(BaseSettings):
     safemode: bool = True
     fetch_format: Literal["array", "frame"] = "array"
     enable_python_native_blobs: bool = True
-    add_hidden_timestamp: bool = False
     filepath_checksum_size_limit: int | None = None
 
     # External stores configuration

src/datajoint/version.py

@@ -1,4 +1,4 @@
 # version bump auto managed by Github Actions:
 # label_prs.yaml(prep), release.yaml(bump), post_release.yaml(edit)
 # manually set this version will be eventually overwritten by the above actions
-__version__ = "2.0.0a10"
+__version__ = "2.0.0a11"

tests/conftest.py

@@ -454,29 +454,6 @@ def minio_client(s3_creds, s3fs_client, teardown=False):
         pass
 
 
-# =============================================================================
-# Utility Fixtures
-# =============================================================================
-
-
-@pytest.fixture(scope="session")
-def monkeysession():
-    with pytest.MonkeyPatch.context() as mp:
-        yield mp
-
-
-@pytest.fixture(scope="module")
-def monkeymodule():
-    with pytest.MonkeyPatch.context() as mp:
-        yield mp
-
-
-@pytest.fixture
-def enable_adapted_types():
-    """Deprecated - custom attribute types no longer require a feature flag."""
-    yield
-
-
 # =============================================================================
 # Cleanup Fixtures
 # =============================================================================

tests/integration/test_declare.py

@@ -4,7 +4,6 @@
 
 import datajoint as dj
 from datajoint.declare import declare
-from datajoint.settings import config
 
 from tests.schema import (
     Auto,
@@ -22,24 +21,6 @@
 )
 
 
-@pytest.fixture(scope="function")
-def enable_add_hidden_timestamp():
-    orig_config_val = config.get("add_hidden_timestamp")
-    config["add_hidden_timestamp"] = True
-    yield
-    if orig_config_val is not None:
-        config["add_hidden_timestamp"] = orig_config_val
-
-
-@pytest.fixture(scope="function")
-def disable_add_hidden_timestamp():
-    orig_config_val = config.get("add_hidden_timestamp")
-    config["add_hidden_timestamp"] = False
-    yield
-    if orig_config_val is not None:
-        config["add_hidden_timestamp"] = orig_config_val
-
-
 def test_schema_decorator(schema_any):
     assert issubclass(Subject, dj.Lookup)
     assert not issubclass(Subject, dj.Part)
@@ -384,26 +365,3 @@ class Table_With_Underscores(dj.Manual):
     schema_any(TableNoUnderscores)
     with pytest.raises(dj.DataJointError, match="must be alphanumeric in CamelCase"):
         schema_any(Table_With_Underscores)
-
-
-def test_add_hidden_timestamp_default_value():
-    config_val = config.get("add_hidden_timestamp")
-    assert config_val is not None and not config_val, "Default value for add_hidden_timestamp is not False"
-
-
-def test_add_hidden_timestamp_enabled(enable_add_hidden_timestamp, schema_any_fresh):
-    assert config["add_hidden_timestamp"], "add_hidden_timestamp is not enabled"
-    msg = f"{Experiment().heading._attributes=}"
-    assert any(a.name.endswith("_timestamp") for a in Experiment().heading._attributes.values()), msg
-    assert any(a.name.startswith("_") for a in Experiment().heading._attributes.values()), msg
-    assert any(a.is_hidden for a in Experiment().heading._attributes.values()), msg
-    assert not any(a.is_hidden for a in Experiment().heading.attributes.values()), msg
-
-
-def test_add_hidden_timestamp_disabled(disable_add_hidden_timestamp, schema_any_fresh):
-    assert not config["add_hidden_timestamp"], "expected add_hidden_timestamp to be False"
-    msg = f"{Experiment().heading._attributes=}"
-    assert not any(a.name.endswith("_timestamp") for a in Experiment().heading._attributes.values()), msg
-    assert not any(a.name.startswith("_") for a in Experiment().heading._attributes.values()), msg
-    assert not any(a.is_hidden for a in Experiment().heading._attributes.values()), msg
-    assert not any(a.is_hidden for a in Experiment().heading.attributes.values()), msg