fix error on checkbox checked change

Author: andrewfan

src/__test__/plugin.test.js

@@ -438,7 +438,10 @@ describe("draft-js-markdown-plugin", () => {
           expect(renderer.component).toBe(CheckableListItem);
           expect(typeof renderer.props.onChangeChecked).toBe("function");
           expect(renderer.props.checked).toBe(true);
-          renderer.props.onChangeChecked();
+          const event = new Event("change", { bubbles: true });
+
+          event.simulated = true;
+          renderer.props.onChangeChecked(event);
           expect(spyOnChangeChecked).toHaveBeenCalledWith(
             currentEditorState,
             block

src/index.js

@@ -297,10 +297,12 @@ const createMarkdownPlugin = (_config = {}) => {
           return {
             component: CheckableListItem,
             props: {
-              onChangeChecked: () =>
+              onChangeChecked: e => {
+                e.preventDefault();
                 setEditorState(
                   CheckableListItemUtils.toggleChecked(getEditorState(), block)
-                ),
+                );
+              },
               checked: !!block.getData().get("checked"),
             },
           };