Fixes to EditorJSSoupElement attribute addition with class (styles NY…

…I yet), add tool_name as class on wagtail blocks.Block 'div' wrapper

README.md

@@ -148,7 +148,7 @@ class TextBlock(EditorJSFeatureStructBlock):
 
     class Meta:
         template = "myapp/text_block.html"
-        allowed_tags = ["div", "h1", "h2", "p"]
+        allowed_tags = ["h1", "h2", "p"]
         # Html looks like:
         #  <h1>{{ self.heading.title }}</h1>
         #  <h2>{{ self.heading.subtitle }}</h2>
@@ -166,6 +166,18 @@ def register_editor_js_features(registry: EditorJSFeatures):
     )
 ```
 
+The block will then be rendered as any structblock, but it will be wrapped in a div with the class `wagtail-text-block` (the feature name).
+
+Example:
+
+    ```html
+    <div class="wagtail-text-block">
+        <h1>My title</h1>
+        <h2>My subtitle</h2>
+        <p>My body</p>
+    </div>
+    ```
+
 ## Settings
 
 ### `EDITORJS_CLEAN_HTML`

wagtail_editorjs/features/blocks.py

@@ -356,10 +356,21 @@ def allowed_tags(self):
     @property
     def allowed_attributes(self):
         if hasattr(self.block, "allowed_attributes"):
-            return self.block.allowed_attributes or {}
-        if hasattr(self.block.meta, "allowed_attributes"):
-            return self.block.meta.allowed_attributes or {}
-        return super().allowed_attributes or {}
+            d = self.block.allowed_attributes
+        elif hasattr(self.block.meta, "allowed_attributes"):
+            d = self.block.meta.allowed_attributes
+        else:
+            d = super().allowed_attributes
+
+        d = d or {}
+
+        class_d = d.setdefault("class", [])
+        if isinstance(class_d, str):
+            class_d = [class_d]
+
+        class_d.append(self.tool_name)
+
+        return d
 
     @property
     def js(self):
@@ -371,7 +382,7 @@ def js(self):
     def render_block_data(self, block: EditorJSBlock, context=None) -> EditorJSElement:
         prefix = block["data"].get("__prefix__") or ""
         value: blocks.StructValue = self.block.value_from_datadict(block["data"].get("block", {}), {}, prefix)
-        return EditorJSSoupElement(f"<div>{ self.block.render(value) }</div>")
+        return EditorJSSoupElement(f"<div class=\"{self.tool_name}\">{ self.block.render(value) }</div>")
 
     @property
     def css(self):

wagtail_editorjs/registry/element/element.py

@@ -104,9 +104,15 @@ def append(self, element: "EditorJSElement"):
 
     def add_attributes(self, **attrs: Union[str, list[str], dict[str, Any]]):
         for key, value in attrs.items():
-            if key == "class_":
-                key = "class"
-            self.soupContent[key] = str(value)
+            if key == "class_" or key == "class":
+                classList = self.soupContent.get("class", [])
+                if isinstance(value, str):
+                    classList.append(value)
+                elif isinstance(value, list):
+                    classList.extend(value)
+                self.soupContent["class"] = classList
+            else:
+                self.soupContent[key] = value
 
 
 def wrapper(element: EditorJSElement, attrs: dict[str, EditorJSElementAttribute] = None, tag: str = "div"):