hunk.code_window:       )
       }
       // Save the new operations.
       if (save || !previous) {
         this.save({ merge })
       }
  
hunk.labels: keep keep keep replace replace replace keep keep
hunk.after_edit:     // If the save flag isn't set, determine whether we should save.
       if (save == null) {
         save = !isOnlySelections(operations)
  
hunk.file_path: src/models/transform.js
hunk.type: replace
file: 
  export default function (state) {
    const { document, selection } = state
    const texts = document.getTexts()
    const first = texts.first()
    const range = selection.merge({
      anchorKey: first.key,
      anchorOffset: first.length,
      focusKey: first.key,
      focusOffset: first.length
    })
  
    return state
      .transform()
      .splitBlockAtRange(range)
      .apply()
  }
  