Bug? ToLowerCase does not work correctly for the Turkish language

[alwaysbusy]

Searching for a bug in my BANano library, I discovered a bug in the .toLowerCase() for the letter I in the Turkish language.

In the Turkish locale, the Unicode LATIN CAPITAL LETTER I becomes a LATIN SMALL LETTER DOTLESS I. That’s not a lowercase “i”.

To test:

#VirtualMachineArgs: -Duser.language=tr

Dim s As String = "IF"
If s.toLowerCase = "if" Then '  the s.toLowerCase returns ıf (no dot on the i)
        Log("True")
Else
        Log("False")
End If

Result:
returns False

Possible solution, being able to add a Locale:

.toLowerCase2(Locale.ROOT)

Edit: the same goes for .toUpperCase()

Alwaysbusy

 

[Erel]

Have you encountered it without explicitly setting user.language=tr?

 

[alwaysbusy]

yes, it happens on every Windows where the language is set to Turkish. This setting is just to emulate it on a non Turkish windows.

It appears to be a known problem: https://garygregory.wordpress.com/2015/11/03/java-lowercase-conversion-turkey/

 

[Erel]

You can call this method when the app starts to set the default locale to US.

Private Sub SetDefaultLocaleToUS
    Dim jo As JavaObject
    jo.InitializeStatic("java.util.Locale").RunMethod("setDefault", Array(jo.GetField("US")))
End Sub

If you want to keep using the native locale for date related methods then set the date format before calling this method.

 

[alwaysbusy]

Yes, that is also the sort of workaround I use now. But on the long run, I believe this should be resolved within the B4J language (especially since Java has a solution for it with its locale parameter). Those are errors one can spend a lot of time on: in my case I lost more than 2 days on it.

 

[Erel]

I agree. It will be fixed. Note that the framework does handle lower casing correctly. There is a technical issue related to the way the string methods are implemented which makes it more difficult to automatically set the locale.