livebook/lib/live_book/evaluator/string_formatter.ex

defmodule LiveBook.Evaluator.StringFormatter do
  @moduledoc false

  # The formatter used by LiveBook for rendering the results.

  @behaviour LiveBook.Evaluator.Formatter

  @impl true
  def format({:ok, value}) do
    inspected = inspect(value, pretty: true, width: 100, syntax_colors: syntax_colors())
    {:inspect, inspected}
  end

  def format({:error, kind, error, stacktrace}) do
    formatted = Exception.format(kind, error, stacktrace)
    {:error, formatted}
  end

  defp syntax_colors() do
    [
      atom: :blue,
      binary: :light_black,
      boolean: :magenta,
      list: :light_black,
      map: :light_black,
      number: :blue,
      nil: :magenta,
      regex: :red,
      string: :green,
      tuple: :light_black,
      reset: :reset
    ]
  end
end