Add live preview to theme picker

helix-term/src/application.rs

@@ -67,26 +67,24 @@ impl Application {
             std::sync::Arc::new(theme::Loader::new(&conf_dir, &helix_loader::runtime_dir()));
 
         let true_color = config.editor.true_color || crate::true_color();
-        let theme = config
-            .theme
-            .as_ref()
-            .and_then(|theme| {
-                theme_loader
-                    .load(theme)
+
+        let theme = match config.theme.as_ref() {
+            Some(theme_name) => {
+                match theme_loader
+                    .load(theme_name)
                     .map_err(|e| {
-                        log::warn!("failed to load theme `{}` - {}", theme, e);
+                        log::warn!("failed to load theme `{}` - {}", theme_name, e);
                         e
                     })
                     .ok()
                     .filter(|theme| (true_color || theme.is_16_color()))
-            })
-            .unwrap_or_else(|| {
-                if true_color {
-                    theme_loader.default()
-                } else {
-                    theme_loader.base16_default()
+                {
+                    Some(theme) => theme,
+                    None => Application::default_theme(theme_loader.clone(), true_color),
                 }
-            });
+            }
+            None => Application::default_theme(theme_loader.clone(), true_color),
+        };
 
         let syn_loader_conf = user_syntax_loader().unwrap_or_else(|err| {
             eprintln!("Bad language config: {}", err);
@@ -103,6 +101,7 @@ impl Application {
             theme_loader.clone(),
             syn_loader.clone(),
             config.editor.clone(),
+            theme.name.clone(),
         );
 
         let editor_view = Box::new(ui::EditorView::new(std::mem::take(&mut config.keys)));
@@ -183,6 +182,14 @@ impl Application {
         Ok(app)
     }
 
+    fn default_theme(theme_loader: Arc<theme::Loader>, true_color: bool) -> theme::Theme {
+        if true_color {
+            theme_loader.default()
+        } else {
+            theme_loader.base16_default()
+        }
+    }
+
     fn render(&mut self) {
         let mut cx = crate::compositor::Context {
             editor: &mut self.editor,