various minor changes suggested by ameba

src/crab/common/frontend/widgets/bios_selection.cr

@@ -36,7 +36,7 @@ class BiosSelection < Resolvable
     ImGui.same_line
     gba_bios_text_buffer_valid = @gba_bios_text_buffer_valid
     ImGui.push_style_color(ImGui::ImGuiCol::Text, RED_TEXT_COL) unless gba_bios_text_buffer_valid
-    ImGui.input_text_with_hint("##gba_bios", "optional", @gba_bios_text_buffer, ImGui::ImGuiInputTextFlags::CallbackAlways) do |data|
+    ImGui.input_text_with_hint("##gba_bios", "optional", @gba_bios_text_buffer, ImGui::ImGuiInputTextFlags::CallbackAlways) do
       @gba_bios_text_buffer_valid = @gba_bios_text_buffer.bytesize == 0 || File.file?(@gba_bios_text_buffer.to_s)
       0 # allow input to proceed
     end

src/crab/gba/bus.cr

@@ -16,7 +16,7 @@ module GBA
     @gpio : GPIO
 
     def initialize(@gba : GBA, bios_path : String)
-      File.open(bios_path) { |file| file.read @bios }
+      File.open(bios_path, &.read(@bios))
       @gpio = GPIO.new(@gba)
     end
 

src/crab/gba/cartridge.cr

@@ -14,7 +14,7 @@ module GBA
     end
 
     def initialize(rom_path : String)
-      File.open(rom_path) { |file| file.read @rom }
+      File.open(rom_path, &.read(@rom))
       # The following logic accounts for improperly dumped ROMs or bad homebrews.
       # All proper ROMs should have a power-of-two size. The handling here is
       # really pretty arbitrary. mGBA chooses to fill the entire ROM address

src/crab/gba/dma.cr

@@ -134,7 +134,7 @@ module GBA
       delta_source = word_size * source_control.delta
       delta_dest = word_size * dest_control.delta
 
-      len.times do |idx|
+      len.times do
         @gba.bus[@dst[channel]] = word_size == 4 ? @gba.bus.read_word(@src[channel]) : @gba.bus.read_half(@src[channel])
         @src[channel] &+= delta_source
         @dst[channel] &+= delta_dest