Tag bulmaform now updates widget attrs instead of resetting them.

hshassets/templatetags/bulma.py

@@ -11,13 +11,17 @@ register = template.Library()
 def bulmaform(form):
     """Templatetag to render forms with bulma styles and elements"""
 
-    # because the <input> tag will be rendered by django's internals, it is easier to give the widgets
-    # a css-class rather than render every <input> tag by mysqlf
+    # append bulma css classes to widgets and let django render these widgets
     for field in form:
+        widget_classes = list()
         # not every form element in bulma has the 'input' css class, so we need to differ here
         if getattr(field.field.widget, 'input_type', None) not in ['checkbox', 'radio']:
-            field.field.widget.attrs = {'class': 'input' + (' is-danger' if field.errors else '')}
-
+            widget_classes.append("input")
+        # highlight fields with errors
+        if field.errors:
+            widget_classes.append("is-danger")
+        # done
+        field.field.widget.attrs["class"] = " ".join(widget_classes)
     if getattr(form, 'layout', None):
         output = render_layout(form.layout, form)
     else: