handle empty post

fixes #196

src/js/editor/post.js

@@ -762,6 +762,9 @@ class PostEditor {
    * @private
    */
   insertPost(position, newPost) {
+    if (newPost.isBlank) {
+      return position;
+    }
     const post = this.editor.post;
     const shouldSplitSection = newPost.sections.length > 1;
 

tests/unit/editor/post-test.js

@@ -941,3 +941,25 @@ test('#insertPost multiple sections, insert at middle', (assert) => {
   assert.equal(nextPosition.offset, post1.sections.objectAt(1).length,
             'nextPosition.offset is correct');
 });
+
+test('#insertPost insert empty post does nothing', (assert) => {
+  const build = Helpers.postAbstract.build;
+  let post1, post2;
+  build(({post, markupSection, marker}) => {
+    post1 = post([markupSection('p', [marker('abc')])]);
+    post2 = post();
+  });
+
+  const mockEditor = renderBuiltAbstract(post1);
+  const position = new Position(post1.sections.head, 1);
+
+  postEditor = new PostEditor(mockEditor);
+  let nextPosition = postEditor.insertPost(position, post2);
+  postEditor.complete();
+
+  assert.equal(post1.sections.length, 1, 'still 1 section');
+  assert.equal(post1.sections.head.text, 'abc', 'same section text');
+  assert.ok(nextPosition.section === post1.sections.head,
+            'nextPosition.section correct');
+  assert.equal(nextPosition.offset, 1, 'nextPosition.offset correct');
+});