Fix test_mode string evaluation in BaseMixin

[Copilot]

Description

String "false" in dj.config["custom"]["test_mode"] evaluated as True because BaseMixin._test_mode returned raw values without type conversion. Any non-empty string is truthy in Python.

Changes:

• src/spyglass/utils/mixins/base.py: Changed _test_mode property to use spyglass.settings.config.test_mode instead of directly reading dj.config. This ensures string-to-boolean conversion via existing str_to_bool().
• tests/utils/test_dj_helper_fn.py: Added test_str_to_bool() covering truthy/falsy strings and edge cases.
• tests/utils/test_mixin.py: Added test_test_mode_property_uses_settings() to verify boolean return type.

Before:

dj.config["custom"]["test_mode"] = "false"
mixin._test_mode  # Returns "false" (string) → bool("false") = True ❌

After:

dj.config["custom"]["test_mode"] = "false"
mixin._test_mode  # Returns False (boolean) via str_to_bool() ✓

Checklist:

• N/A. If this PR should be accompanied by a release, I have updated the CITATION.cff
• N/A. If this PR edits table definitions, I have included an alter snippet for release notes.
• N/A. If this PR makes changes to position, I ran the relevant tests locally.
• N/A. If this PR makes user-facing changes, I have added/edited docs/notebooks to reflect the changes
• I have updated the CHANGELOG.md with PR number and description.

Original prompt

Problem

Fix issue #1528: When test_mode is set as a string value "false" in dj.config, the BaseMixin._test_mode property incorrectly evaluates it as True (since any non-empty string is truthy in Python). This causes Spyglass to run in test mode unintentionally, triggering warnings like accept_divergence called in test mode, returning False w/o prompt.

Proposed Solution

Modify the _test_mode property in src/spyglass/utils/mixins/base.py to use spyglass.settings.test_mode which already correctly handles string-to-boolean conversion using the str_to_bool() function.

Implementation Details

In src/spyglass/utils/mixins/base.py, the _test_mode property currently reads:

@property
def _test_mode(self) -> bool:
    """Return True if in test mode.

    Avoids circular import. Prevents prompt on delete.

    Note: Using @property instead of @cached_property so we always get
    current value from dj.config, even if test_mode changes after first access.

    Used by ...
    - BaseMixin._spyglass_version
    - HelpersMixin
    """
    import datajoint as dj

    # Check dj.config directly instead of importing module-level variable
    # which gets stale if load_config() is called after initial import
    return dj.config.get("custom", {}).get("test_mode", False)

Change it to:

@property
def _test_mode(self) -> bool:
    """Return True if in test mode.

    Avoids circular import. Prevents prompt on delete.

    Note: Using @property instead of @cached_property so we always get
    current value from settings, even if test_mode changes after first access.

    Used by ...
    - BaseMixin._spyglass_version
    - HelpersMixin
    """
    from spyglass.settings import config as sg_config

    return sg_config.test_mode

This ensures that the string-to-boolean conversion happens correctly via SpyglassConfig.test_mode property which uses str_to_bool().

Expected Behavior After Fix

• When test_mode is set to string "false" or "False", it will correctly evaluate to boolean False
• Users will receive proper prompts during ingestion
• No spurious test mode warnings will appear

Testing

Verify that:

1. Setting "test_mode": "false" (string) in config now correctly evaluates to False
2. Setting "test_mode": false (boolean) in config continues to work
3. Setting "test_mode": "true" (string) correctly evaluates to True
4. Setting "test_mode": true (boolean) continues to work
5. Existing tests continue to pass

Fixes #1528

This pull request was created from Copilot chat.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[CBroz1]

Is this config a dictionary? I think this needs...

Suggested change

	return sg_config.test_mode
	return sg_config.get('test_mode', False)

[samuelbray32]

Switched it to just import test_mode directly