Implement 'mix escript' task

Author: alco

lib/mix/lib/mix/local.ex

@@ -13,6 +13,15 @@ defmodule Mix.Local do
  Path.join(Mix.Utils.mix_home, "archives")
  end
 
+ @doc """
+ The path for local escripts.
+
+ Check `mix escript` for info.
+ """
+ def escripts_path do
+ Path.join(Mix.Utils.mix_home, "escripts")
+ end
+
  @doc """
  Appends archives paths into Erlang code path.
  """

lib/mix/lib/mix/tasks/archive.ex

@@ -1,13 +1,13 @@
 defmodule Mix.Tasks.Archive do
  use Mix.Task
 
- @shortdoc "Lists all archives"
+ @shortdoc "Lists installed archives"
 
  @moduledoc """
  Lists all installed archives.
 
  Archives are typically installed at `~/.mix/archives`
- although the installation path can be customize by
+ although the installation path can be customized by
  setting the `MIX_ARCHIVES` environment variable.
 
  Since archives are specific to Elixir versions, it is

lib/mix/lib/mix/tasks/escript.ex

@@ -0,0 +1,48 @@
+defmodule Mix.Tasks.Escript do
+ use Mix.Task
+
+ @shortdoc "List installed escripts."
+
+ @moduledoc ~S"""
+ Lists all installed escripts.
+
+ Escripts are installed at `~/.mix/escripts`. Add that path to your `PATH` environment variable
+ to be able to run installed escripts from any directory.
+ """
+
+ use Bitwise
+
+ @spec run(OptionParser.argv) :: :ok
+ def run(_) do
+ escripts_path = Mix.Local.escripts_path
+
+ escripts =
+ escripts_path
+ |> list_dir
+ |> Enum.filter(fn filename -> executable?(Path.join([escripts_path, filename])) end)
+
+ if escripts == [] do
+ Mix.shell.info "No escripts currently installed."
+ else
+ Enum.each escripts, fn filename ->
+ Mix.shell.info "* #{filename}"
+ end
+
+ Mix.shell.info "Escripts installed at: #{escripts_path}"
+ end
+ end
+
+ defp list_dir(path) do
+ case File.ls(path) do
+ {:ok, list} -> list
+ _ -> []
+ end
+ end
+
+ defp executable?(path) do
+ owner_exec_bit = 0o00100
+ group_exec_bit = 0o00010
+ other_exec_bit = 0o00001
+ (File.stat!(path).mode &&& (owner_exec_bit ||| group_exec_bit ||| other_exec_bit)) != 0
+ end
+end