Fix editor above with point (#5235)

* Fix Editor.above with point

Editor.above should ignore checking text nodes (they're never above
anything) and continue looking for ancestors.
Otherwise it won't be able to find any above nodes when starting to look
from a text node.

* Add changeset

.changeset/wet-tigers-double.md

@@ -0,0 +1,5 @@
+---
+'slate': patch
+---
+
+Fixed Editor.above method that always returned undefined with Point location

packages/slate/src/interfaces/editor.ts

@@ -359,7 +359,7 @@ export const Editor: EditorInterface = {
       match,
       reverse,
     })) {
-      if (Text.isText(n)) return
+      if (Text.isText(n)) continue
       if (Range.isRange(at)) {
         if (
           Path.isAncestor(p, at.anchor.path) &&

packages/slate/test/interfaces/Editor/above/point.tsx

@@ -0,0 +1,18 @@
+/** @jsx jsx */
+
+import { Editor } from 'slate'
+import { jsx } from '../../..'
+
+export const input = (
+  <editor>
+    <block>
+      <block>one</block>
+    </block>
+  </editor>
+)
+
+export const test = editor => {
+  return Editor.above(editor, { at: { path: [0, 0, 0], offset: 1 } })
+}
+
+export const output = [<block>one</block>, [0, 0]]