[iOS/HybridGlobalization] No space between time and AM/PM designator

[tipa]

Description

When using hybrid globalization on iOS and using the short time specifier, there is no space in front of the "AM" or "PM".

Reproduction Steps

var date = DateTime.Today + TimeSpan.FromHours(15) + TimeSpan.FromMinutes(15);
var culture = new CultureInfo("en-US");
System.Diagnostics.Debug.WriteLine(date.ToString("t", culture));

Expected behavior

3:15 PM

Actual behavior

3:15PM

Regression?

No response

Known Workarounds

No response

Configuration

macos 14.2.8053/8.0.100 SDK 8.0.200
ios 17.2.8053/8.0.100 SDK 8.0.200

iOS 17.2

Other information

The same problem happens when using the long time format specified ("T").
The space is present as expected when not using hybrid globalization

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[ilonatommy]

@mkhamoyan, in

runtime/src/native/libs/System.Globalization.Native/pal_locale.m

Line 698 in 43b7b53

const char* GlobalizationNative_GetLocaleTimeFormatNative(const char* localeName, int shortFormat)

we are using methods that according to the documentation:
https://developer.apple.com/documentation/foundation/nsdateformatterstyle/nsdateformattershortstyle
https://developer.apple.com/documentation/foundation/nsdateformatterstyle/nsdateformattermediumstyle
should return formats with the space. Is it possible that we format it on the fly? Or might it be a behavioral change between iOS's ICU version?

[mkhamoyan]

We see bahavioural change as there was a fix in ICU flow ( see #83589) and now

runtime/src/libraries/System.Private.CoreLib/src/System/Globalization/CultureData.Icu.cs

Line 338 in 0c64e66

private static string ConvertIcuTimeFormatString(ReadOnlySpan<char> icuFormatString)

and

runtime/src/libraries/System.Private.CoreLib/src/System/Globalization/CultureData.iOS.cs

Line 79 in 0c64e66

private static string ConvertNativeTimeFormatString(string nativeFormatString)

have different implementations.
I will open a PR to use same function for both flows.

[vitek-karas]

@matouskozak fyi

[mkhamoyan]

I am not able to reproduce this issue in the .NET 8 repo (works as expected on .Net 9 also).
@tipa Could you please specify whether you created the project using dotnet new maui or dotnet new ios?

[tipa]

I can still reproduce this with .NET 8. I am using dotnet new ios.
It only happens when using <HybridGlobalization>true</HybridGlobalization>

[mkhamoyan]

Thanks! I can reproduce with dotnet new ios

[kalin-todorov]

I can still reproduce this with .NET 8. I am using dotnet new ios. It only happens when using <HybridGlobalization>true</HybridGlobalization>

I'm reproducing the issue in .Net 9 project without setting HybridGlobalization. The project was created with dotnet new ios and I'm using the latest preview 4.

[mkhamoyan]

In .NET 9 HybridGlobalization is the default and only mode.
I was previously unable to reproduce the issue because I was targeting an iOS device running version 16.7.8, which uses an older ICU version.

It appears that recent ICU versions have introduced a change where regular spaces are replaced with non-breaking spaces (NBSP / \u00A0) or narrow non-breaking spaces (NNBSP / \u202F). For more details, see the related ICU change.

I will open a PR to handle these cases properly.