deps: Upgrade freetype-sys to version 0.21

[LeoDog896]

Integrate PistonDevelopers/freetype-sys@b785722.

[mrobinson]

I'm not sure that bundling HarfBuzz should imply that FreeType is automatically bundled as well. Perhaps a user only wants to bundle HarfBuzz, but use the system FreeType. This change would make that impossible.

[waywardmonkeys]

Also, IIRC, if you are building harfbuzz with freetype support, it needs the freetype headers, which this wouldn't provide for the build, right?

[waywardmonkeys]

I think that's why I filed #235.

[LeoDog896]

I'm unaware of how to prevent the freetype library from being bundled twice. It only includes the headers 😅 this should be fine then.

[mrobinson]

I don't thin you need another feature for this. Features are additive, so one should just need to make sure that freetype-sys is has the bundled feature when compiling. This is something that someone using rust-harfbuzz can do without having to expose a new feature here.

[LeoDog896]

Should the freetype-bundled feature be exposed in the harfbuzz wrapper only then, since features of subdependencies can't be specified?

[LeoDog896]

I don't believe it's possible in CLI to enable features of sub dependencies (it is possible in Cargo.toml, though!)

[LeoDog896]

Since the packaged freetype version on Ubuntu 20 is 2.11.1 which is lower than the required freetype version for freetype-sys, it should be bundled on CI - though, should it be this CI's responsibility to test freetype from the system rather than its default bundling behavior?

[mrobinson]

I've modified this branch to simply update to version 0.21 of freetype-sys. Changes:

• Use the ubuntu-24.04 GitHub image. The issue here is that the version of FreeType used in ubunut-latest is too old. In addition, the FreeType development package needs to be installed.
• Add the freetype-sys/bundled feature when necessary. It seems that FreeType is used by default even on platforms where it likely doesn't make sense (Windows).
• Added a line in the README explaining that this may be necessary.

[LeoDog896]

Oh! I did not know that feature syntax was possible - though, how should #235 be done?

[mrobinson]

Oh! I did not know that feature syntax was possible - though, how should #235 be done?

This needs a bit of exploration I think. I'm sure other crates have run into this issue and we should check what they do.

[narodnik]

I had to patch harfbuzz_rs to do https://github.com/narodnik/hbrs2/blob/master/build.rs#L22

cfg.define("HAVE_FREETYPE", "1");

Right now this is a blocker for me to switch to harfbuzz_sys