Add unit test for testing insertTextByKey with marks

test/transforms/fixtures/by-key/insert-text-by-key/middle-text-with-marks/index.js

@@ -0,0 +1,29 @@
+
+import assert from 'assert'
+
+export default function (state) {
+  const { document, selection } = state
+  const texts = document.getTexts()
+  const firstText = texts.first()
+  const secondText = texts.get(1)
+
+  const nextSelection = selection.merge({
+      anchorKey: firstText.key,
+      focusKey: firstText.key,
+      anchorOffset: 2,
+      focusOffset: 2
+  })
+
+  const next = state
+    .transform()
+    .moveTo(nextSelection)
+    .insertTextByKey(secondText.key, 2, 'XX', [ { type: 'bold' } ])
+    .apply()
+
+    assert.deepEqual(
+      next.selection.toJS(),
+      nextSelection.toJS()
+    )
+
+  return next
+}

test/transforms/fixtures/by-key/insert-text-by-key/middle-text-with-marks/input.yaml

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+
+nodes:
+  - kind: block
+    type: paragraph
+    nodes:
+      - kind: text
+        text: outside
+  - kind: block
+    type: paragraph
+    nodes:
+      - kind: text
+        text: hello

test/transforms/fixtures/by-key/insert-text-by-key/middle-text-with-marks/output.yaml

@@ -0,0 +1,17 @@
+
+nodes:
+  - kind: block
+    type: paragraph
+    nodes:
+      - kind: text
+        text: outside
+  - kind: block
+    type: paragraph
+    nodes:
+      - kind: text
+        ranges:
+          - text: he
+          - text: XX
+            marks:
+              - type: bold
+          - text: llo