fix: keep empty line between lists

apps/editor/src/__test__/unit/convertor.spec.ts

@@ -1098,4 +1098,34 @@ describe('Convertor', () => {
 
     expect(result).toBe(`<strong>"test"</strong>a`);
   });
+
+  it('should convert empty line which is between lists of wysiwig to <br>', () => {
+    const wwNodeJson = {
+      type: 'doc',
+      content: [
+        {
+          type: 'bulletList',
+          content: [
+            {
+              type: 'listItem',
+              content: [
+                { type: 'paragraph', content: [{ type: 'text', text: 'test_1' }] },
+                { type: 'paragraph', content: [] },
+              ],
+            },
+            {
+              type: 'listItem',
+              content: [{ type: 'paragraph', content: [{ type: 'text', text: 'test_2' }] }],
+            },
+          ],
+        },
+      ],
+    };
+
+    const wwNode = Node.fromJSON(schema, wwNodeJson);
+
+    const result = convertor.toMarkdownText(wwNode);
+
+    expect(result).toBe(`* test\\_1\n<br>\n* test\\_2`);
+  });
 });

apps/editor/src/convertors/toMarkdown/toMdConvertorState.ts

@@ -78,6 +78,14 @@ export default class ToMdConvertorState {
     return '';
   }
 
+  setDelim(delim: string) {
+    this.delim = delim;
+  }
+
+  getDelim() {
+    return this.delim;
+  }
+
   flushClose(size?: number) {
     if (!this.stopNewline && this.closed) {
       if (!this.isInBlank()) {

apps/editor/src/convertors/toMarkdown/toMdNodeTypeWriters.ts

@@ -83,6 +83,14 @@ export const nodeTypeWriters: ToMdNodeTypeWriterMap = {
       if (emptyNode && prevEmptyNode) {
         state.write('<br>\n');
       } else if (emptyNode && !prevEmptyNode && !firstChildNode) {
+        if (parent?.type.name === 'listItem') {
+          const prevDelim = state.getDelim();
+
+          state.setDelim('');
+          state.write('<br>');
+
+          state.setDelim(prevDelim);
+        }
         state.write('\n');
       } else {
         state.convertInline(node);

apps/editor/types/convertor.d.ts

@@ -45,6 +45,8 @@ export type FirstDelimFn = (index: number) => string;
 export interface ToMdConvertorState {
   stopNewline: boolean;
   inTable: boolean;
+  getDelim(): string;
+  setDelim(delim: string): void;
   flushClose(size?: number): void;
   wrapBlock(delim: string, firstDelim: string | null, node: ProsemirrorNode, fn: () => void): void;
   ensureNewLine(): void;