Reload language config with :config-reload (#5239)

helix-term/src/application.rs

@@ -397,40 +397,51 @@ pub fn handle_config_events(&mut self, config_event: ConfigEvent) {
         self.editor.refresh_config();
     }
 
+    /// refresh language config after config change
+    fn refresh_language_config(&mut self) -> Result<(), Error> {
+        let syntax_config = helix_core::config::user_syntax_loader()
+            .map_err(|err| anyhow::anyhow!("Failed to load language config: {}", err))?;
+
+        self.syn_loader = std::sync::Arc::new(syntax::Loader::new(syntax_config));
+        for document in self.editor.documents.values_mut() {
+            document.detect_language(self.syn_loader.clone());
+        }
+
+        Ok(())
+    }
+
     /// Refresh theme after config change
-    fn refresh_theme(&mut self, config: &Config) {
+    fn refresh_theme(&mut self, config: &Config) -> Result<(), Error> {
         if let Some(theme) = config.theme.clone() {
             let true_color = self.true_color();
-            match self.theme_loader.load(&theme) {
+            let theme = self
-                Ok(theme) => {
+                .theme_loader
+                .load(&theme)
+                .map_err(|err| anyhow::anyhow!("Failed to load theme `{}`: {}", theme, err))?;
+
             if true_color || theme.is_16_color() {
                 self.editor.set_theme(theme);
             } else {
-                        self.editor
+                anyhow::bail!("theme requires truecolor support, which is not available")
-                            .set_error("theme requires truecolor support, which is not available");
-                    }
-                }
-                Err(err) => {
-                    let err_string = format!("failed to load theme `{}` - {}", theme, err);
-                    self.editor.set_error(err_string);
-                }
             }
         }
+
+        Ok(())
     }
 
     fn refresh_config(&mut self) {
-        match Config::load_default() {
+        let mut refresh_config = || -> Result<(), Error> {
-            Ok(config) => {
+            let default_config = Config::load_default()
-                self.refresh_theme(&config);
+                .map_err(|err| anyhow::anyhow!("Failed to load config: {}", err))?;
+            self.refresh_language_config()?;
+            self.refresh_theme(&default_config)?;
+            Ok(())
+        };
 
-                // Store new config
+        if let Err(err) = refresh_config() {
-                self.config.store(Arc::new(config));
-            }
-            Err(err) => {
             self.editor.set_error(err.to_string());
         }
     }
-    }
 
     fn true_color(&self) -> bool {
         self.config.load().editor.true_color || crate::true_color()