themes: add bundled theme registry and picker

crates/assets/Cargo.toml

@@ -10,6 +10,9 @@ anyhow.workspace = true
 rust-embed.workspace = true
 gpui-kit.workspace = true
 
+[dev-dependencies]
+serde_json.workspace = true
+
 # On wasm there is no filesystem to read from, so rust-embed's debug-mode
 # disk loading returns nothing; embed the assets even in debug builds.
 [target.'cfg(target_arch = "wasm32")'.dependencies]

crates/assets/src/lib.rs

@@ -8,6 +8,7 @@ use rust_embed::RustEmbed;
 #[include = "fonts/**/*"]
 #[include = "brand/**/*"]
 #[include = "icons/**/*"]
+#[include = "themes/**/*"]
 #[exclude = "*.DS_Store"]
 pub struct Assets;
 
@@ -74,3 +75,29 @@ impl AssetSource for Assets {
             .collect())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use gpui_kit::component::ThemeSet;
+
+    use super::*;
+
+    /// Every bundled theme file must parse against gpui-kit's schema.
+    #[test]
+    fn bundled_themes_parse() {
+        let mut count = 0;
+
+        for entry in Assets::iter().filter(|p| p.starts_with("themes/")) {
+            let file = Assets::get(&entry).expect("theme file exists");
+            let content = std::str::from_utf8(&file.data).expect("theme is UTF-8");
+            let set: ThemeSet = serde_json::from_str(content).expect("theme parses");
+            assert!(!set.themes.is_empty(), "{entry} has no themes");
+            count += set.themes.len();
+        }
+
+        assert!(
+            count >= 36,
+            "expected the bundled gpui-kit themes, got {count}"
+        );
+    }
+}