BackTest: Daylight Savings Fix

[davidlatte]

When running a long backtest that goes across Daylight Savings transitions, lumibot is reporting the start time at 10:30am instead of 9:30am. Basically the DST offset that existed when the backtest began continues through out the entire backtest regardless of DST transitions. The fix is pretty straightforward which is to normalize the time after incrementing it with a timedelta() to ensure that the proper DST accounting takes place.

Additionally, all of the various timezone calls throughout the code have been standardized to use the Lumibot default.

Description by Korbit AI

What change is being made?

Update timezone handling by using a unified timezone configuration LUMIBOT_DEFAULT_PYTZ for better consistency and fix daylight savings time issues in the lumibot codebase.

Why are these changes being made?

These changes address inconsistent timezone management which could lead to errors especially around daylight savings time transitions. By introducing a single source of truth for timezone handling (LUMIBOT_DEFAULT_PYTZ), the codebase improves readability, maintainability, and correctness regarding datetime operations across different modules.

Is this description stale? Ask me to generate a new description by commenting /korbit-generate-pr-description

[korbit-ai]

I've completed my review and didn't find any issues.

Files scanned

​

File Path	Reviewed
lumibot/data_sources/tradier_data.py	✅
lumibot/tools/thetadata_helper.py	✅
lumibot/backtesting/backtesting_broker.py	✅
lumibot/data_sources/interactive_brokers_rest_data.py	✅
lumibot/strategies/_strategy.py	✅

Explore our documentation to understand the languages and file types we support and the files we ignore.

Need a new review? Comment /korbit-review on this PR and I'll review your latest changes.

Korbit Guide: Usage and Customization

Interacting with Korbit

• You can manually ask Korbit to review your PR using the /korbit-review command in a comment at the root of your PR.
• You can ask Korbit to generate a new PR description using the /korbit-generate-pr-description command in any comment on your PR.
• Too many Korbit comments? I can resolve all my comment threads if you use the /korbit-resolve command in any comment on your PR.
• Chat with Korbit on issues we post by tagging @korbit-ai in your reply.
• Help train Korbit to improve your reviews by giving a 👍 or 👎 on the comments Korbit posts.

Customizing Korbit

• Check out our docs on how you can make Korbit work best for you and your team.
• Customize Korbit for your organization through the Korbit Console.

Current Korbit Configuration

General Settings

​

Setting	Value
Review Schedule	Automatic excluding drafts
Max Issue Count	10
Automatic PR Descriptions	✅

Issue Categories

​

Category	Enabled
Naming	✅
Database Operations	✅
Documentation	✅
Logging	✅
Error Handling	✅
Systems and Environment	✅
Objects and Data Structures	✅
Readability and Maintainability	✅
Asynchronous Processing	✅
Design Patterns	✅
Third-Party Libraries	✅
Performance	✅
Security	✅
Functionality	✅

Feedback and Support

• Tell us what you think of Korbit
• Schedule a call with our team
• Email us @ [email protected]