Add --color for easy enabling and disabling of coloring (#14183)

Author: josevalim

Diff for: bin/elixir

@@ -18,6 +18,7 @@ Usage: $(basename "$0") [options] [.exs file] [data]
   -pz "PATH"                   Appends the given path to Erlang code path (*)
   -v, --version                Prints Erlang/OTP and Elixir versions (standalone)
 
+  --color BOOL                 Enables or disables ANSI coloring
   --erl "SWITCHES"             Switches to be passed down to Erlang (*)
   --eval "COMMAND"             Evaluates the given command, same as -e (*)
   --logger-otp-reports BOOL    Enables or disables OTP reporting
@@ -114,7 +115,7 @@ while [ $I -le $LENGTH ]; do
     -v|--no-halt)
         C=1
         ;;
-    -e|-r|-pr|-pa|-pz|--eval|--remsh|--dot-iex|--dbg)
+    -e|-r|-pr|-pa|-pz|--eval|--remsh|--dot-iex|--dbg|--color)
         C=2
         ;;
     --rpc-eval)

Diff for: bin/elixir.bat

@@ -24,6 +24,7 @@ echo   -pa "PATH"                   Prepends the given path to Erlang code path
 echo   -pz "PATH"                   Appends the given path to Erlang code path (*)
 echo   -v, --version                Prints Erlang/OTP and Elixir versions (standalone)
 echo.
+echo   --color BOOL                 Enables or disables ANSI coloring
 echo   --erl "SWITCHES"             Switches to be passed down to Erlang (*)
 echo   --eval "COMMAND"             Evaluates the given command, same as -e (*)
 echo   --logger-otp-reports BOOL    Enables or disables OTP reporting
@@ -110,6 +111,7 @@ if ""==!par:--no-halt=!   (goto startloop)
 if ""==!par:--remsh=!     (shift && goto startloop)
 if ""==!par:--dot-iex=!   (shift && goto startloop)
 if ""==!par:--dbg=!       (shift && goto startloop)
+if ""==!par:--color=!     (shift && goto startloop)
 rem ******* ERLANG PARAMETERS **********************
 if ""==!par:--boot=!                (set "parsErlang=!parsErlang! -boot "%~1"" && shift && goto startloop)
 if ""==!par:--boot-var=!            (set "parsErlang=!parsErlang! -boot_var "%~1" "%~2"" && shift && shift && goto startloop)

Diff for: bin/elixir.ps1

@@ -26,6 +26,7 @@ Usage: $scriptName [options] [.exs file] [data]
   -pz "PATH"                   Appends the given path to Erlang code path (*)
   -v, --version                Prints Erlang/OTP and Elixir versions (standalone)
 
+  --color                      Enables or disables ANSI coloring
   --erl "SWITCHES"             Switches to be passed down to Erlang (*)
   --eval "COMMAND"             Evaluates the given command, same as -e (*)
   --logger-otp-reports BOOL    Enables or disables OTP reporting
@@ -106,7 +107,7 @@ $runErlLog = $null
   $private:arg = $allArgs[$i]
 
   switch -exact ($arg) {
-    { $_ -in @("-e", "-r", "-pr", "-pa", "-pz", "--eval", "--remsh", "--dot-iex", "--dbg") } {
+    { $_ -in @("-e", "-r", "-pr", "-pa", "-pz", "--eval", "--remsh", "--dot-iex", "--dbg", "--color") } {
       ++$i
       break
     }

Diff for: lib/elixir/lib/kernel/cli.ex

@@ -295,6 +295,24 @@ defmodule Kernel.CLI do
     parse_argv(t, %{config | commands: [{:parallel_require, h} | config.commands]})
   end
 
+  defp parse_argv([~c"--color", value | t], config) do
+    config =
+      case value do
+        ~c"true" ->
+          Application.put_env(:elixir, :ansi_enabled, true)
+          config
+
+        ~c"false" ->
+          Application.put_env(:elixir, :ansi_enabled, false)
+          config
+
+        _ ->
+          %{config | errors: ["--color : must be a boolean" | config.errors]}
+      end
+
+    parse_argv(t, config)
+  end
+
   ## Compiler
 
   defp parse_argv([~c"-o", h | t], %{mode: :elixirc} = config) do