Fix dbg on Erlang/OTP 25- (#12697)

Author: josevalim

bin/elixir

@@ -94,6 +94,7 @@ starts_with () {
 }
 
 ERL_EXEC="erl"
+MODE="cli"
 I=1
 E=0
 LENGTH=$#
@@ -104,9 +105,13 @@ while [ $I -le $LENGTH ]; do
   S=0
   C=0
   case "$1" in
-    +elixirc|+iex)
+    +elixirc)
         C=1
         ;;
+    +iex)
+        C=1
+        MODE="iex"
+        ;;
     -v|--no-halt|--dbg)
         C=1
         ;;
@@ -223,7 +228,7 @@ fi
 ERTS_BIN=
 ERTS_BIN="$ERTS_BIN"
 
-set -- "$ERTS_BIN$ERL_EXEC" -noshell -elixir_root "$SCRIPT_PATH"/../lib -pa "$SCRIPT_PATH"/../lib/elixir/ebin $ELIXIR_ERL_OPTIONS -s elixir start_cli $ERL "$@"
+set -- "$ERTS_BIN$ERL_EXEC" -noshell -elixir_root "$SCRIPT_PATH"/../lib -pa "$SCRIPT_PATH"/../lib/elixir/ebin $ELIXIR_ERL_OPTIONS -s elixir start_$MODE $ERL "$@"
 
 if [ -n "$RUN_ERL_PIPE" ]; then
   ESCAPED=""

bin/elixir.bat

@@ -82,7 +82,7 @@ rem Option which determines whether the loop is over
 set endLoop=0
 
 rem Designates which mode / Elixir component to run as
-set runMode="elixir"
+set runMode="cli"
 
 rem Designates the path to the current script
 set SCRIPT_PATH=%~dp0
@@ -106,7 +106,7 @@ if !endLoop! == 1 (
 )
 rem ******* EXECUTION OPTIONS **********************
 if !par!=="--werl"   (set useWerl=1 && goto startloop)
-if !par!=="+iex" (set parsElixir=!parsElixir! +iex && goto startloop)
+if !par!=="+iex"     (set parsElixir=!parsElixir! +iex && set runMode="iex" && goto startloop)
 if !par!=="+elixirc" (set parsElixir=!parsElixir! +elixirc && goto startloop)
 rem ******* EVAL PARAMETERS ************************
 if ""==!par:-e=! (
@@ -164,8 +164,13 @@ reg query HKCU\Console /v VirtualTerminalLevel 2>nul | findstr /e "0x1" >nul 2>n
 if %errorlevel% == 0 (
   set beforeExtra=-elixir ansi_enabled true !beforeExtra!
 )
+if !runMode! == "iex" (
+  set beforeExtra=-s elixir start_iex !beforeExtra!
+) else (
+  set beforeExtra=-s elixir start_cli !beforeExtra!
+)
 
-set beforeExtra=-noshell -elixir_root "!SCRIPT_PATH!..\lib" -pa "!SCRIPT_PATH!..\lib\elixir\ebin" -s elixir start_cli !beforeExtra!
+set beforeExtra=-noshell -elixir_root "!SCRIPT_PATH!..\lib" -pa "!SCRIPT_PATH!..\lib\elixir\ebin" !beforeExtra!
 
 if defined ELIXIR_CLI_DRY_RUN (
    if defined useWerl (

bin/iex

@@ -30,4 +30,4 @@ readlink_f () {
 
 SELF=$(readlink_f "$0")
 SCRIPT_PATH=$(dirname "$SELF")
-exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user elixir" -e ":elixir.start_iex()" +iex "$@"
+exec "$SCRIPT_PATH"/elixir --no-halt --erl "-user elixir" +iex "$@"

bin/iex.bat

@@ -24,6 +24,6 @@ goto end
 
 :run
 if defined IEX_WITH_WERL (set __ELIXIR_IEX_FLAGS=--werl) else (set __ELIXIR_IEX_FLAGS=)
-call "%~dp0\elixir.bat" --no-halt --erl "-user elixir" -e ":elixir.start_iex()" +iex %__ELIXIR_IEX_FLAGS% %*
+call "%~dp0\elixir.bat" --no-halt --erl "-user elixir" +iex %__ELIXIR_IEX_FLAGS% %*
 :end
 endlocal

lib/elixir/src/elixir.erl

@@ -192,7 +192,8 @@ start_cli() ->
   'Elixir.Kernel.CLI':main(init:get_plain_arguments()),
   elixir_config:booted().
 
-%% TODO: Delete prim_tty branches and -user on Erlang/OTP 26.
+%% TODO: Delete prim_tty branches and -user on Erlang/OTP 26
+%% and add "-e :elixir.start_iex" to bin/iex instead of $MODE.
 start() ->
   case code:ensure_loaded(prim_tty) of
     {module, _} ->
@@ -207,6 +208,7 @@ start() ->
 start_iex() ->
   case code:ensure_loaded(prim_tty) of
     {module, _} ->
+      start_cli(),
       spawn(fun() ->
         elixir_config:wait_until_booted(),
         (shell:whereis() =:= undefined) andalso 'Elixir.IEx':cli()

lib/iex/lib/iex.ex

@@ -536,6 +536,9 @@ defmodule IEx do
 
   @doc """
   Returns `true` if IEx was started, `false` otherwise.
+
+  This means the IEx application was started, but not
+  that its CLI interface is running.
   """
   @spec started?() :: boolean()
   def started? do
@@ -857,6 +860,8 @@ defmodule IEx do
 
   # This is a callback invoked by Erlang shell utilities
   # when someone presses Ctrl+G and adds `s 'Elixir.IEx'`.
+  # Let's consider exposing this as iex:start() and rename
+  # elixir:start_iex() to iex:cli().
   @doc false
   def start(opts \\ [], mfa \\ {IEx, :dont_display_result, []}) do
     # TODO: Keep only this branch, delete optional args and mfa,
@@ -869,10 +874,13 @@ defmodule IEx do
       end)
     else
       spawn(fn ->
-        {:ok, _} = Application.ensure_all_started(:elixir)
-        System.wait_until_booted()
-        :ok = :io.setopts(binary: true, encoding: :unicode)
+        case :init.notify_when_started(self()) do
+          :started -> :ok
+          _ -> :init.wait_until_started()
+        end
+
         {:ok, _} = Application.ensure_all_started(:iex)
+        :ok = :io.setopts(binary: true, encoding: :unicode)
         _ = for fun <- Enum.reverse(after_spawn()), do: fun.()
         IEx.Server.run_from_shell(opts, mfa)
       end)

lib/iex/lib/iex/cli.ex

@@ -6,7 +6,7 @@ defmodule IEx.CLI do
 
   def deprecated do
     if tty_works?() do
-      :user_drv.start([:"tty_sl -c -e", old_tty_args()])
+      :user_drv.start([:"tty_sl -c -e", tty_args()])
     else
       if get_remsh(:init.get_plain_arguments()) do
         IO.puts(
@@ -20,14 +20,10 @@ defmodule IEx.CLI do
       # IEx.Broker is capable of considering all groups under user_drv but
       # when we use :user.start(), we need to explicitly register it instead.
       # If we don't register, pry doesn't work.
-      IEx.start([register: true] ++ options())
+      IEx.start([register: true] ++ options(), {:elixir, :start_cli, []})
     end
   end
 
-  def prompt(_n) do
-    []
-  end
-
   # Check if tty works. If it does not, we fall back to the
   # simple/dumb terminal. This is starting the linked in
   # driver twice, it would be nice and appropriate if we had
@@ -41,7 +37,7 @@ defmodule IEx.CLI do
     end
   end
 
-  defp old_tty_args do
+  defp tty_args do
     if remote = get_remsh(:init.get_plain_arguments()) do
       remote = List.to_atom(append_hostname(remote))
 
@@ -77,7 +73,7 @@ defmodule IEx.CLI do
   end
 
   defp local_start_mfa do
-    {IEx, :start, [options()]}
+    {IEx, :start, [options(), {:elixir, :start_cli, []}]}
   end
 
   def remote_start(parent, ref) do