JavaScript: improved indentation in multi-line expressions

src/source.cc

@@ -2073,15 +2073,30 @@ bool Source::View::on_key_press_event_bracket_language(GdkEventKey* key) {
       // return (\n
       // ReactDOM.render(\n  <div>\n
       if(open_non_curly_bracket_iter_found && (*open_non_curly_bracket_iter=='[' || *open_non_curly_bracket_iter=='(')) {
-        if(condition_iter.get_line()==open_non_curly_bracket_iter.get_line())
-          tabs=get_line_before(start_iter)+tab;
+        // If next line should have an extra tab:
+        if(condition_iter.get_line()==open_non_curly_bracket_iter.get_line()) {
+          get_buffer()->insert_at_cursor("\n"+tabs+tab);
+          scroll_to(get_buffer()->get_insert());
+          return true;
+        }
+        // Indent as in current or next line:
         else {
-          start_iter=get_tabs_end_iter(get_buffer()->get_iter_at_line(condition_iter.get_line()));
-          tabs=get_line_before(start_iter);
+          auto start_iter=get_tabs_end_iter(get_buffer()->get_iter_at_line(condition_iter.get_line()));
+          auto tabs=get_line_before(start_iter);
+          
+          int line_nr=iter.get_line();
+          if(iter.ends_line() && (line_nr+1)<get_buffer()->get_line_count()) {
+            auto next_line_tabs=get_line_before(get_tabs_end_iter(line_nr+1));
+            if(next_line_tabs.size()>tabs.size()) {
+              get_buffer()->insert_at_cursor("\n"+next_line_tabs);
+              scroll_to(get_buffer()->get_insert());
+              return true;
+            }
+          }
+          get_buffer()->insert_at_cursor("\n"+tabs);
+          scroll_to(get_buffer()->get_insert());
+          return true;
         }
-        get_buffer()->insert_at_cursor("\n"+tabs);
-        scroll_to(get_buffer()->get_insert());
-        return true;
       }
     }