✨ code review of dates.py

[joocer]

The code appears to be a Python module that includes functions for working with dates and intervals. Here are some observations and suggestions for improvement:

Code Organization:

The code is missing a docstring for the date_range function. Adding a docstring would improve code readability and provide information about the function's purpose and usage.
There are multiple imports from the datetime module. It would be cleaner to group them together on a single line.
Variable Names and Comments:

Variable names like dte, num_months, cursor, and value could be more descriptive to improve code readability. Consider using more meaningful names that reflect the purpose of the variables.
Some comments are missing or incomplete. It would be helpful to include comments explaining the purpose of certain code blocks, especially in complex functions like parse_iso.
Performance Improvements:

The add_months function could be optimized. Instead of using the datetime constructor twice, it would be more efficient to use datetime.replace to modify the year and month.
The regular expression pattern TIMEDELTA_PATTERN is compiled outside the function. This is a good practice to improve performance because the pattern doesn't need to be recompiled each time the function is called.
Error Handling:

The date_range function raises a ValueError when the start and end dates are equal or when the start date is greater than the end date. It would be better to use a custom exception type that provides more specific information about the error.
Type Annotations:

The type hints used in the function signatures are helpful for understanding the expected input and return types. However, the type hints for the current_date parameter in the add_interval function and the dt parameter in the date_trunc function could be more specific. Instead of using Union[date, datetime], it would be clearer to use datetime for these parameters since the functions rely on specific attributes and methods of the datetime class.