DatePickerElement initial_date validation is incorrect

[arturshyshko]

Description

While trying to pass initial_date attribute to DatePickerElement constructor, it raises

slack.errors.SlackObjectFormationError: initial_date attribute must be in format ‘YYYY-MM-DD’

even though you pass there correct date format, like "2020-03-08".

This happens because initial_date_valid for DatePickerElement uses incorrect regex for verifying date - r"\d{4}-[01][12]-[0123]\d".
This regex only matches 01, 02, 11 and 12 months.

What type of issue is this? (place an x in one of the [ ])

• bug
• enhancement (feature request)
• question
• documentation related
• testing related
• discussion

Requirements (place an x in each of the [ ])

• I've read and understood the Contributing guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've searched for any related issues and avoided creating a duplicate issue.

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Bug Report

Reproducible in:

slackclient version: 2.2.0

python version: 3.7.0

OS version(s): MacOS Catalina Version 10.15.3

Steps to reproduce:

1. Create DatePickerElement with action_id, placeholder and initial_date attributes (month in initial_date should be from 03 to 10);
2. Call its to_dict() method.

Expected result:

Expected result is a dict object with action_id, initial_date, type and placeholder attributes.

Actual result:

SlackObjectFormationError is being raised.

Attachments:

[seratch]

Thank you very much for taking the time to report this. I've confirmed the bug and am working on the fix. I will come up with a PR for fixing this and will release a new version soon.

[seratch]

👋 slackclient 2.6.0rc1 is out. The pre-release version contains fixes for your issue described here.
https://pypi.org/project/slackclient/2.6.0rc1/

One week later from now, we'll be releasing version 2.6.0 to PyPI.

If you have a chance, could you try the release candidate version out and let us know your feedback? Thank you very much for being patient with this issue.