add heading command

packages/core/src/Editor.ts

@@ -71,6 +71,7 @@ export class Editor extends EventEmitter {
     this.registerCommand('setContent', require('./commands/setContent').default)
     this.registerCommand('clearContent', require('./commands/clearContent').default)
     this.registerCommand('removeMarks', require('./commands/removeMarks').default)
+    this.registerCommand('toggleBlockType', require('./commands/toggleBlockType').default)
     
     if (this.options.injectCSS) {
       require('./style.css')

packages/core/src/commands/toggleBlockType.ts

@@ -0,0 +1,30 @@
+import { NodeType } from 'prosemirror-model'
+import { setBlockType } from 'prosemirror-commands'
+import { Editor } from '../Editor'
+import nodeIsActive from '../utils/nodeIsActive'
+
+declare module '../Editor' {
+  interface Editor {
+    toggleBlockType(type: NodeType, toggleType: NodeType, attrs?: {}): Editor,
+  }
+}
+
+export default function toggleBlockType(
+  next: Function,
+  editor: Editor,
+  type: NodeType,
+  toggleType: NodeType,
+  attrs?: {},
+): void {
+  const { view, state } = editor
+  const isActive = nodeIsActive(state, type, attrs)
+
+  if (isActive) {
+    setBlockType(toggleType)(view.state, view.dispatch)
+    next()
+    return
+  }
+
+  setBlockType(type, attrs)(view.state, view.dispatch)
+  next()
+}