lib/mix/tasks/hex_latest.ex

hex_latest.ex

defmodule Mix.Tasks.Hex.Latest do
  @doc """
  ## Example usage:
  
  `mix hex.latest jason`
  
  Or you can copy the output with `pbcopy` like this:
  
  `mix hex.latest jason | pbcopy`
  """
  use Mix.Task

  @shortdoc "Get the latest version of hex package"
  @impl Mix.Task
  def run([package]) do
    with {output, 0} <- System.cmd("mix", ["hex.info", package], stderr_to_stdout: true),
         [_all, match] <- Regex.run(~r/Config: ({.*})/, output) do
      Mix.Shell.IO.info(match <> ",")
    else
      {error_message, error_code} when is_integer(error_code) ->
        error_message
        |> String.trim()
        |> Mix.Shell.IO.error()
    end
  end

  def run(_) do
    Mix.raise("""
    Invalid arguments. Expected:

    mix hex.latest [PACKAGE]
    """)
  end
end