add getSplittedAttributes helper

packages/core/src/commands/splitBlock.ts

@@ -2,6 +2,7 @@ import { canSplit } from 'prosemirror-transform'
 import { ContentMatch, Fragment } from 'prosemirror-model'
 import { EditorState, NodeSelection, TextSelection } from 'prosemirror-state'
 import { Command } from '../types'
+import getSplittedAttributes from '../helpers/getSplittedAttributes'
 
 function defaultBlockAt(match: ContentMatch) {
   for (let i = 0; i < match.edgeCount; i + 1) {
@@ -42,22 +43,12 @@ export const splitBlock = (options: Partial<SplitBlockOptions> = {}): Command =>
   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
-    }))
+  const newAttributes = getSplittedAttributes(
+    extensionAttributes,
+    $from.node().type.name,
+    $from.node().attrs,
+  )
 
   if (selection instanceof NodeSelection && selection.node.isBlock) {
     if (!$from.parentOffset || !canSplit(doc, $from.pos)) {

packages/core/src/commands/splitListItem.ts

@@ -8,6 +8,7 @@ import { canSplit } from 'prosemirror-transform'
 import { TextSelection } from 'prosemirror-state'
 import { Command } from '../types'
 import getNodeType from '../helpers/getNodeType'
+import getSplittedAttributes from '../helpers/getSplittedAttributes'
 
 /**
  * Splits one list item into two list items.
@@ -32,6 +33,8 @@ export const splitListItem = (typeOrName: string | NodeType): Command => ({
     return false
   }
 
+  const extensionAttributes = editor.extensionManager.attributes
+
   if ($from.parent.content.size === 0 && $from.node(-1).childCount === $from.indexAfter(-1)) {
     // In an empty block. If this is a nested list, the wrapping
     // list item should be split. Otherwise, bail out and let next
@@ -55,7 +58,12 @@ export const splitListItem = (typeOrName: string | NodeType): Command => ({
       }
 
       // Add a second list item with an empty default start node
-      const nextType = type.contentMatch.defaultType?.createAndFill($from.node().attrs) || undefined
+      const newNextTypeAttributes = getSplittedAttributes(
+        extensionAttributes,
+        $from.node().type.name,
+        $from.node().attrs,
+      )
+      const nextType = type.contentMatch.defaultType?.createAndFill(newNextTypeAttributes) || undefined
       wrap = wrap.append(Fragment.from(type.createAndFill(null, nextType) || undefined))
 
       tr
@@ -75,35 +83,16 @@ export const splitListItem = (typeOrName: string | NodeType): Command => ({
     ? grandParent.contentMatchAt(0).defaultType
     : null
 
-  const extensionAttributes = editor.extensionManager.attributes
-  const currentTypeAttributes = grandParent.attrs
-  const currentNextTypeAttributes = $from.node().attrs
-  const newTypeAttributes = Object.fromEntries(Object
-    .entries(currentTypeAttributes)
-    .filter(([name]) => {
-      const extensionAttribute = extensionAttributes.find(item => {
-        return item.type === grandParent.type.name && item.name === name
-      })
-
-      if (!extensionAttribute) {
-        return false
-      }
-
-      return extensionAttribute.attribute.keepOnSplit
-    }))
-  const newNextTypeAttributes = Object.fromEntries(Object
-    .entries(currentNextTypeAttributes)
-    .filter(([name]) => {
-      const extensionAttribute = extensionAttributes.find(item => {
-        return item.type === $from.node().type.name && item.name === name
-      })
-
-      if (!extensionAttribute) {
-        return false
-      }
-
-      return extensionAttribute.attribute.keepOnSplit
-    }))
+  const newTypeAttributes = getSplittedAttributes(
+    extensionAttributes,
+    grandParent.type.name,
+    grandParent.attrs,
+  )
+  const newNextTypeAttributes = getSplittedAttributes(
+    extensionAttributes,
+    $from.node().type.name,
+    $from.node().attrs,
+  )
 
   tr.delete($from.pos, $to.pos)
 

packages/core/src/helpers/getSplittedAttributes.ts

@@ -0,0 +1,21 @@
+import { AnyObject, ExtensionAttribute } from '../types'
+
+export default function getSplittedAttributes(
+  extensionAttributes: ExtensionAttribute[],
+  typeName: string,
+  attributes: AnyObject,
+): AnyObject {
+  return Object.fromEntries(Object
+    .entries(attributes)
+    .filter(([name]) => {
+      const extensionAttribute = extensionAttributes.find(item => {
+        return item.type === typeName && item.name === name
+      })
+
+      if (!extensionAttribute) {
+        return false
+      }
+
+      return extensionAttribute.attribute.keepOnSplit
+    }))
+}