const DEFAULT_STATE = {
  searchTerm: ''
}

const rootReducer = (state = DEFAULT_STATE, action) => {
  switch (action.type) {

  }
}

export default rootReducer

@@ -119,16 +119,47 @@
 type) %7B%0A
+    default:%0A      return state
 %0A  %7D%0A%7D%0A%0A

Add default case for switch statement