Optimizer failing with new_data, if start_date and end_date are actually start and end date of new_data

[pro100olga]

expanded_str = [date.strftime(c.DATE_FORMAT) for date in expanded_dates]
here raises an error, if expanded_dates is None, which happens if start_date and end_date are respectively min and max dates of the new_data.
This leads to inability to run optimization with new_data, unless start_date or end_date is not actual start or end dates of new_data - which seems counterintuitive.

[gousesb]

Hi @pro100olga ,

Thank you for bringing this bug to our attention. We have resolved the issue, and the fix is available in the unreleased Meridian version.

# Install meridian: from GitHub @HEAD
# !pip install --upgrade "google-meridian[colab,and-cuda] @ git+https://github.com/google/meridian.git@main"

For information on previous Meridian changes and unreleased feature updates, please refer to our Change Log. We appreciate you taking the time to help us improve Meridian for all users.

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Google Meridian Support Team