...

spec/clim/compile_time_error_spec/files/main_command_default_help.cr

@@ -0,0 +1,22 @@
+require "./../../../../src/clim"
+
+class MyCli < Clim
+  main_command do
+    run do |opts, args|
+    end
+    sub_command "sub_command" do
+      desc "sub_comand."
+      option "-n NUM", type: Int32, desc: "Number.", default: 0
+      run do |opts, args|
+      end
+      sub_command "sub_sub_command" do
+        desc "sub_sub_comand description."
+        option "-p PASSWORD", type: String, desc: "Password.", required: true
+        run do |opts, args|
+        end
+      end
+    end
+  end
+end
+
+MyCli.start(ARGV)

spec/clim/compile_time_error_spec/stdout_spec.cr

@@ -15,6 +15,27 @@ describe "STDOUT spec, " do
         sub_sub_command   sub_sub_comand description.
 
 
+    DISPLAY
+  end
+  it "display main_command help." do
+    `crystal run spec/clim/compile_time_error_spec/files/main_command_default_help.cr --no-color -- sub_command --help`.should eq <<-DISPLAY
+
+      sub_comand.
+
+      Usage:
+
+        sub_command [options] [arguments]
+
+      Options:
+
+        -n NUM                           Number. [type:Int32] [default:0]
+        --help                           Show this help.
+
+      Sub Commands:
+
+        sub_sub_command   sub_sub_comand description.
+
+
     DISPLAY
   end
 end