fix cupertino date picker column width calculation - #151142

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@HosamHasanRamadan thanks for contributing! Welcome!
Can you add a test that verifies that this works as expected?

Hi @Piinks
I was trying to add tests to this change, but I didn't know where to start.

• _getColumnWidth is private
• the function depends on flutter_localizations which is not part of flutter package

Can you guide me through ?
Or if there is a similar test that I can read because I didn't find any test in date_picker_test.dart to old code.

Another PR fixing a similar issue with a different implementation was filed here: #151128

Or if there is a similar test that I can read because I didn't find any test in date_picker_test.dart to old code.

This is a tricky thing to test, the person in the other PR is having the same problem. It looks like the test needs to both override the localizations with one that triggers the issue and use a different font then what the tests use by default. The font used by the tests have a standard spacing that may not trigger this issue. See this comment and the one above it.

Thanks @MitchellGoodwin
Using Localizations.override fixes the localization problem and managed to render Arabic months.
Now I have problem with the font , it seems like monospaced font is used during test.
The problem isn't reproducible in this case.
How can I override the font is this situation?

The other PR has the same issue, and looks like they were able to load Roboto. Link to comment on the section. I don't know enough about how the fonts load in the tests to know if it's a safe test though.

@MitchellGoodwin
I managed to add test without exposing any private members in CupertinoDatePicker file.
I used Local('pr') for locale and months values , I didn't manage to test it with Arabic values.

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Going to close this in favor of #151128. Feel free to comment on that PR. If that one is closed for any reason, also feel free to reopen this one.