Load system UI font

[colinmarc]

In Webkit, I can use the system-ui family to grab, for example, the San Francisco font on mac.

Is there a way to do that with this library? It would be nice to match the font to the OS, when available.

I tried the following:

select_best_match(
    &[font_kit::family_name::FamilyName::Title(
        "system-ui".to_string(),
    )],
    &font_kit::properties::Properties::new(),
)

But no dice.

[colinmarc]

Looks like on mac, this is available in a newer version of core-text than is currently pinned by this library:

https://github.com/servo/core-foundation-rs/blob/master/core-text/src/font.rs#L240

[jayvdb]

#234 has updated core-text to the latest.