amend gvar $shell to lvar shell && make Shell.simply_question singleton method

Author: hasumikin

mrbgems/picoruby-bin-r2p2/tools/mrblib/app.rb

@@ -8,9 +8,9 @@
 
   Shell.bootstrap("../etc/init.d/r2p2")
 
-  $shell = Shell.new
-  $shell.show_logo
-  $shell.start
+  shell = Shell.new
+  shell.show_logo
+  shell.start
 rescue => e
   puts e.message
   exit

mrbgems/picoruby-shell/mrblib/shell.rb

@@ -143,13 +143,7 @@ def self.setup_sdcard(spi)
     end
   end
 
-  def initialize(clean: false)
-    require 'editor' # To save memory
-    clean and IO.wait_terminal(timeout: 2) and IO.clear_screen
-    @editor = Editor::Line.new
-  end
-
-  def simple_question(question, &block)
+  def self.simple_question(question, &block)
     while true
       print question
       answer = ""
@@ -167,6 +161,12 @@ def simple_question(question, &block)
     end
   end
 
+  def initialize(clean: false)
+    require 'editor' # To save memory
+    clean and IO.wait_terminal(timeout: 2) and IO.clear_screen
+    @editor = Editor::Line.new
+  end
+
   LOGO_COLOR = "\e[32;1m"
   AUTHOR_COLOR = "\e[36;1m"
   if RUBY_ENGINE == "mruby/c"

mrbgems/picoruby-shell/shell_executables/setup_rtc.rb

@@ -3,7 +3,7 @@
 # TODO: move /etc/init.c/r2p2-rtc
 i2c_unit, sda, scl = :RP2040_I2C0, 4, 5
 
-$shell.simple_question("Do you have RTC? (sda:#{sda}, scl:#{scl}) [y/N] ") do |answer|
+Shell.simple_question("Do you have RTC? (sda:#{sda}, scl:#{scl}) [y/N] ") do |answer|
   case answer
   when "y", "Y"
     i2c = I2C.new(unit: i2c_unit, sda_pin: sda, scl_pin: scl)

mrbgems/picoruby-shell/shell_executables/setup_sdcard.rb

@@ -3,7 +3,7 @@
 # TODO: move /etc/init.c/r2p2-sdcard
 spi_unit, sck, cipo, copi, cs = :RP2040_SPI0, 22, 20, 23, 21
 
-$shell.simple_question("Do you have SD card? (sck:#{sck}, cipo:#{cipo}, copi:#{copi}, cs:#{cs}) [y/N] ") do |answer|
+Shell.simple_question("Do you have SD card? (sck:#{sck}, cipo:#{cipo}, copi:#{copi}, cs:#{cs}) [y/N] ") do |answer|
   case answer
   when "y", "Y"
     spi = SPI.new(frequency: 5_000_000, unit: spi_unit,

mrbgems/picoruby-shell/sig/shell.rbs

@@ -3,11 +3,6 @@
 # Revealed types
 #  /home/hasumi/work/prk_firmware/lib/picoruby/mrbgems/picoruby-shell/mrblib/command.rb:69 #=> nil
 
-type rtc_t = PCF8523
-
-$shell: Shell
-$sandbox: Sandbox
-
 # Classes
 
 $LOAD_PATH: Array[String]
@@ -28,9 +23,9 @@ class Shell
   def self.ensure_system_file: (String path, String code, ?(Integer | nil) crc) -> void
   def self.setup_system_files: (?(String | nil) root, ?force: bool) -> void
   def self.bootstrap: (String file) -> bool
+  def self.simple_question: (String question) { (String answer) -> boolish } -> void
 
   def initialize: (?clean: bool) -> void
-  def simple_question: (String question) { (String answer) -> boolish } -> void
   def show_logo: -> nil
   def start: (?Symbol mode) -> nil
   def run_shell: -> void