add keepOnSplit option to attributes

packages/core/src/ExtensionManager.ts

@@ -95,15 +95,18 @@ export default class ExtensionManager {
       .flat()
   }
 
+  get attributes() {
+    return getAttributesFromExtensions(this.extensions)
+  }
+
   get nodeViews() {
     const { editor } = this
     const { nodeExtensions } = splitExtensions(this.extensions)
-    const allAttributes = getAttributesFromExtensions(this.extensions)
 
     return Object.fromEntries(nodeExtensions
       .filter(extension => !!extension.config.addNodeView)
       .map(extension => {
-        const extensionAttributes = allAttributes.filter(attribute => attribute.type === extension.config.name)
+        const extensionAttributes = this.attributes.filter(attribute => attribute.type === extension.config.name)
         const context = {
           options: extension.options,
           editor,

packages/core/src/commands/splitBlock.ts

@@ -15,7 +15,6 @@ function defaultBlockAt(match: ContentMatch) {
 }
 
 export interface SplitBlockOptions {
-  withAttributes: boolean,
   withMarks: boolean,
 }
 
@@ -31,15 +30,35 @@ function keepMarks(state: EditorState) {
 /**
  * Forks a new node from an existing node.
  */
-export const splitBlock = (options: Partial<SplitBlockOptions> = {}): Command => ({ tr, state, dispatch }) => {
+export const splitBlock = (options: Partial<SplitBlockOptions> = {}): Command => ({
+  tr,
+  state,
+  dispatch,
+  editor,
+}) => {
   const defaultOptions: SplitBlockOptions = {
-    withAttributes: false,
     withMarks: true,
   }
   const config = { ...defaultOptions, ...options }
   const { selection, doc } = tr
   const { $from, $to } = selection
 
+  const extensionAttributes = editor.extensionManager.attributes
+    .filter(item => item.type === $from.node().type.name)
+
+  const currentAttributes = $from.node().attrs
+  const newAttributes = Object.fromEntries(Object
+    .entries(currentAttributes)
+    .filter(([name]) => {
+      const extensionAttribute = extensionAttributes.find(item => item.name === name)
+
+      if (!extensionAttribute) {
+        return false
+      }
+
+      return extensionAttribute.attribute.keepOnSplit
+    }))
+
   if (selection instanceof NodeSelection && selection.node.isBlock) {
     if (!$from.parentOffset || !canSplit(doc, $from.pos)) {
       return false
@@ -74,9 +93,7 @@ export const splitBlock = (options: Partial<SplitBlockOptions> = {}): Command =>
     let types = atEnd && deflt
       ? [{
         type: deflt,
-        attrs: config.withAttributes
-          ? $from.node().attrs
-          : {},
+        attrs: newAttributes,
       }]
       : undefined
 
@@ -91,9 +108,7 @@ export const splitBlock = (options: Partial<SplitBlockOptions> = {}): Command =>
       types = deflt
         ? [{
           type: deflt,
-          attrs: config.withAttributes
-            ? $from.node().attrs
-            : {},
+          attrs: newAttributes,
         }]
         : undefined
     }

packages/core/src/helpers/getAttributesFromExtensions.ts

@@ -20,6 +20,7 @@ export default function getAttributesFromExtensions(extensions: Extensions): Ext
     rendered: true,
     renderHTML: null,
     parseHTML: null,
+    keepOnSplit: true,
   }
 
   extensions.forEach(extension => {

packages/core/src/types.ts

@@ -60,6 +60,7 @@ export type Attribute = {
   rendered?: boolean,
   renderHTML?: ((attributes: { [key: string]: any }) => { [key: string]: any } | null) | null,
   parseHTML?: ((element: HTMLElement) => { [key: string]: any } | null) | null,
+  keepOnSplit: boolean,
 }
 
 export type Attributes = {