add tests (#3535)

packages/slate/test/interfaces/Node/first/success.js

@@ -0,0 +1,19 @@
+/** @jsx jsx  */
+
+import { Node } from 'slate'
+import { jsx } from 'slate-hyperscript'
+
+export const input = (
+  <editor>
+    <element>
+      <text key="a" />
+      <text key="b" />
+    </element>
+  </editor>
+)
+
+export const test = value => {
+  return Node.first(value, [0])
+}
+
+export const output = [<text key="a" />, [0, 0]]

packages/slate/test/interfaces/Node/last/success.js

@@ -0,0 +1,19 @@
+/** @jsx jsx  */
+
+import { Node } from 'slate'
+import { jsx } from 'slate-hyperscript'
+
+export const input = (
+  <editor>
+    <element>
+      <text key="a" />
+      <text key="b" />
+    </element>
+  </editor>
+)
+
+export const test = value => {
+  return Node.last(value, [0])
+}
+
+export const output = [<text key="b" />, [0, 1]]