assertColumnEquality truncates long columns

[MrPowers]

Here's some example code:

it("provides a good error message for wide columns") {
  val df = spark.createDF(
    List(
      ("this is a really really really really long sentence", "this is a really really really really long sentence and the diff is hidden"),
      ("animation", "animation"),
      ("bill", "bill")
    ), List(
      ("sentence1", StringType, true),
      ("sentence2", StringType, true)
    )
  )

  assertColumnEquality(df, "sentence1", "sentence2")
}

It'll output this error message:

assertColumnEquality should at least provide an option so the output doesn't truncate. Something like assertColumnEquality(df, "sentence1", "sentence2", truncate=false).