node-repl-row-counter.ts

function renderLines(lines: number = 2): number {
  const columns = process.stdout.columns

  const resultingText = ("a").repeat((columns * lines))

  const result = resultingText.length / columns // -- in testing this was like 1.99999467 so I ceil it

  return Math.ceil(result) // -- lines
}

function countTextLines(text: string): number {
  const columns = process.stdout.columns

  const result = text.length / columns // -- in testing this was like 1.99999467 so I ceil it

  return Math.ceil(result) // -- lines
}

console.log("Rendering 2 lines\n", renderLines(2)) // - 2
console.log("Rendering 13 lines\n", renderLines(13)) // - 13

console.log("Rendering 4 lines of text and counting lines\n", countTextLines(("a").repeat(process.stdout.columns * 4)))
console.log("Rendering 14 lines of text and counting lines\n", countTextLines(("a").repeat(process.stdout.columns * 14)))