stormlicht: use features instead of cfg to select chromes

Technically features are supposed to be additive, which the
chrome selection is not. However, the interaction between
cfg parameters and cargo is so incredibly annoying that
its better to just use them anyways.

Fixes #21

python/build.py

@@ -48,14 +48,13 @@ def run_stormlicht(args, unknown_args):
     if not args.no_backtrace:
         environment["RUST_BACKTRACE"] = "1"
 
-    environment["RUSTFLAGS"] = (
-        environment.get("RUSTFLAGS", "") + f'--cfg chrome="{args.chrome}"'
-    )
-
     if args.miri:
         arguments = ["miri", "run"]
     else:
         arguments = ["run"]
+
+    if args.chrome == "glazier":
+        arguments += ["--no-default-features", "--features=chrome-glazier"]
 
     cmd = (
         util.Command.create("cargo")
@@ -167,7 +166,7 @@ def run():
     parser_run.add_argument(
         "--chrome",
         choices=["glazier", "gtk"],
-        default="glazier",
+        default="gtk",
         help="Which browser chrome to use",
     )
     parser_run.set_defaults(handler=run_stormlicht)

stormlicht/Cargo.toml

@@ -22,16 +22,24 @@ image = { workspace = true }
 sl-std = { workspace = true }
 settings = { workspace = true }
 
-[target.'cfg(chrome = "glazier")'.dependencies]
-glazier = { git = "https://github.com/linebender/glazier" }
-softbuffer = { version = "0.2" }
+# Glazier-only dependencies
+glazier = { git = "https://github.com/linebender/glazier", optional = true }
+softbuffer = { version = "0.2", optional = true }
 
-[target.'cfg(chrome = "gtk")'.dependencies]
-gtk = { package = "gtk4", version = "0.8", features = ["v4_10"] }
-adw = { version = "0.6", package = "libadwaita" }
+# GTK-only dependencies
+gtk = { package = "gtk4", version = "0.8", features = [
+    "v4_10",
+], optional = true }
+adw = { version = "0.6", package = "libadwaita", optional = true }
 
-[target.'cfg(chrome = "gtk")'.build-dependencies]
-glib-build-tools = "0.18.0"
+[features]
+default = ["chrome-gtk"]
+chrome-gtk = ["dep:gtk", "dep:adw", "dep:glib-build-tools"]
+chrome-glazier = ["dep:glazier", "dep:softbuffer"]
+
+
+[build-dependencies]
+glib-build-tools = { version = "0.18.0", optional = true }
 
 [lints]
 workspace = true

stormlicht/build.rs

@@ -6,7 +6,7 @@ fn main() {
 
     get_environment_info();
 
-    #[cfg(chrome = "gtk")]
+    #[cfg(feature = "chrome-gtk")]
     compile_glib_resources();
 }
 
@@ -28,7 +28,7 @@ fn get_environment_info() {
     );
 }
 
-#[cfg(chrome = "gtk")]
+#[cfg(feature = "chrome-gtk")]
 fn compile_glib_resources() {
     glib_build_tools::compile_resources(
         &["resources"],

stormlicht/src/chrome/mod.rs

@@ -1,9 +1,9 @@
 cfg_match! {
-    cfg(chrome = "glazier") => {
+    cfg(feature = "chrome-glazier") => {
         mod glazier;
         pub use glazier::run;
     }
-    cfg(chrome = "gtk") => {
+    cfg(feature = "chrome-gtk") => {
         mod gtk;
         pub use gtk::run;
     }