Add --dot-iex command line option to IEx

It allows one to override the standard locations where .iex is searched and also makes it possible to disable .iex loading completely.

Author: alco

bin/iex

@@ -14,6 +14,8 @@ if [ $# -gt 0 ] && ([ $1 = "--help" ] || [ $1 = "-h" ]); then
  --name \"name\" Makes and assigns a name to the distributed node
  --sname \"name\" Makes and assigns a short name to the distributed node
  --remsh \"name\" Connects to a node using a remote shell
+ --dot-iex \"path\" Overrides default .iex file and uses path instead;
+ path can be empty, then no file will be loaded
 
 ** Options marked with (*) can be given more than once
 ** Options given after the .exs file or -- are passed down to the executed code
@@ -33,4 +35,4 @@ readlink_f () {
 
 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-ELIXIR_NO_CLI=1 exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user Elixir-IEx-CLI" +iex "$@"
+ELIXIR_NO_CLI=1 exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user Elixir-IEx-CLI" +iex "$@"

lib/elixir/lib/kernel/cli.ex

@@ -222,6 +222,12 @@ defmodule Kernel.CLI do
  { config, t }
  end
 
+ # This clause is here so that Kernel.CLI does not error out with "unknown
+ # option"
+ defp process_iex(["--dot-iex",_|t], config) do
+ process_iex t, config
+ end
+
  defp process_iex([opt,_|t], config) when opt in ["--remsh"] do
  process_iex t, config
  end

lib/iex/lib/iex.ex

@@ -1,5 +1,5 @@
 defrecord IEx.Config, binding: nil, cache: '', counter: 1, scope: nil,
- result: nil, load_dot_iex: true
+ result: nil, dot_iex_path: nil
 
 defmodule IEx do
  @moduledoc %B"""
@@ -87,6 +87,9 @@ defmodule IEx do
  iex(1)> value
  13
 
+ It is possible to override the default loading sequence for .iex file by
+ supplying the --dot-iex option to iex. See `iex --help`.
+
  ## Expressions in IEx
 
  As an interactive shell, IEx evalutes expressions. This has some
@@ -206,7 +209,7 @@ defmodule IEx do
  IEx.Config[
  binding: opts[:binding] || [],
  scope: scope,
- load_dot_iex: Keyword.get(opts, :load_dot_iex, true),
+ dot_iex_path: Keyword.get(opts, :dot_iex_path),
  ]
  end
 

lib/iex/lib/iex/cli.ex

@@ -19,7 +19,8 @@ defmodule IEx.CLI do
  else
  :user.start
  IO.puts "Warning: could not run smart terminal, falling back to dumb one"
- IEx.start([], fn -> :elixir.start_cli end)
+ config = [dot_iex_path: find_dot_iex(:init.get_plain_arguments)]
+ IEx.start(config, fn -> :elixir.start_cli end)
  end
  end
 
@@ -37,12 +38,15 @@ defmodule IEx.CLI do
  end
 
  defp tty do
+ plain_args = :init.get_plain_arguments
+
+ config = [dot_iex_path: find_dot_iex(plain_args)]
  function = fn ->
- IEx.start([], fn -> :elixir.start_cli end)
+ IEx.start(config, fn -> :elixir.start_cli end)
  end
 
  args =
- if remote = get_remsh(:init.get_plain_arguments) do
+ if remote = get_remsh(plain_args) do
  unless is_alive do
  function = fn ->
  IO.puts(:stderr, "In order to use --remsh, you need to name the current node using --name or --sname. Aborting...")
@@ -60,6 +64,10 @@ defmodule IEx.CLI do
  :user_drv.start([:"tty_sl -c -e", args])
  end
 
+ defp find_dot_iex(['--dot-iex',h|_]), do: :unicode.characters_to_binary(h)
+ defp find_dot_iex([_|t]), do: find_dot_iex(t)
+ defp find_dot_iex([]), do: nil
+
  defp get_remsh(['--remsh',h|_]), do: list_to_atom(h)
  defp get_remsh([_|t]), do: get_remsh(t)
  defp get_remsh([]), do: nil

lib/iex/lib/iex/server.ex

@@ -10,12 +10,18 @@ defmodule IEx.Server do
 
  """
  def start(config) do
- IO.puts "Interactive Elixir (#{System.version}) - press Ctrl+C to exit (type h() ENTER for help)"
  Process.put :iex_history, []
+
  { _, _, scope } = :elixir.eval('require IEx.Helpers', [], 0, config.scope)
  config = config.scope(scope)
- if config.load_dot_iex, do:
- config = load_dot_iex(config)
+
+ config = case config.dot_iex_path do
+ "" -> config # don't load anything
+ nil -> load_dot_iex(config) # load .iex from predefined locations
+ path -> load_dot_iex(config, path) # load from `path`
+ end
+
+ IO.puts "Interactive Elixir (#{System.version}) - press Ctrl+C to exit (type h() ENTER for help)"
  do_loop(config)
  end
 
@@ -91,8 +97,12 @@ defmodule IEx.Server do
 
  # Locates and loads an .iex file from one of predefined locations. Returns
  # new config.
- defp load_dot_iex(config) do
- candidates = Enum.map [".iex", "~/.iex"], Path.expand(&1)
+ defp load_dot_iex(config, path // nil) do
+ candidates = if path do
+ [path]
+ else
+ Enum.map [".iex", "~/.iex"], Path.expand(&1)
+ end
  path = Enum.find candidates, fn path -> File.regular?(path) end
  if nil?(path) do
  config