Add ability to start week span on Sunday

[oakt]

Pull Request Checklist

Thank you for taking the time to improve Arrow! Before submitting your pull request, please check all appropriate boxes:

• [x] 🧪 Added tests for changed code.
• [x] 🛠️ All tests pass when run locally (run tox or make test to find out!).
• [x] 🧹 All linting checks pass when run locally (run tox -e lint or make lint to find out!).
• [ ] 📚 Updated documentation for changed code.
• [x] ⏩ Code is up-to-date with the master branch.

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Description of Changes

Issue #355 fixed

Changed isoweekday function in arrow.py so it takes in extra parameter startSunday, which is a bool (default false) that determines if week should start on Sunday instead of Monday. If true, it returns (1-7) for (Sunday-Saturday) instead of (Monday-Sunday).

Changed span function to also take in startSunday parameter (via kwargs). If startSunday is true, span will call isoweekday(True) instead of isoweekday(), so span('week') will return a week starting on Sunday and ending on Monday.

Close: #355

[codecov-commenter]

Codecov Report

Merging #812 into master will not change coverage. The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #812   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           10        10           
  Lines         1757      1763    +6     
  Branches       300       302    +2     
=========================================
+ Hits          1757      1763    +6     

Impacted Files	Coverage Δ
arrow/arrow.py	100.00% <100.00%> (ø)

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[krisfremen]

Hi @oakt, thanks for the contribution. It seems that the linting CI is failing. Can you run pre-commit run --all-files to fix the issues and push again?

[oakt]

Unfortunately the pre-commit command isn't working on my device (MacOS), however the code did pass "make lint" initially. Is there another command I can try? Thanks

[jadchaar]

Hey @oakt, you need to install pre-commit either globally or in the virtual environment: pip install pre-commit. Or you can install it with home brew!

Running make lint requires pre-commit, so you probably already have it in the virtual env. If it runs, you need to add and commit the changes files.

[systemcatch]

We should probably implement this as an ability to start the week on any day, not just Sunday. Let's revisit this once we have a better implementation strategy.