make class method tests arm tests

test/mains/test_class.rb

@@ -0,0 +1,37 @@
+require_relative "helper"
+
+module Mains
+  class ClassTester < MiniTest::Test
+    include MainsHelper
+
+    def test_simple_call
+      @input = code("return Space.get")
+      assert_result 5 , ""
+    end
+
+    def test_inst_get
+      @input = code("return Space.get" , "@inst = 5;return @inst")
+      assert_result 5 , ""
+    end
+
+    def test_inst_set
+      setter = "def self.set(num); @inst = num;end ;"
+      @input = code("Space.set(6);return Space.get" , "return @inst" , setter)
+      assert_result 6 , ""
+    end
+
+    def code( main , get = "return 5" , extra = "")
+      @input = <<MAIN
+      class Space
+        #{extra}
+        def self.get
+          #{get}
+        end
+        def main(arg)
+          #{main}
+        end
+      end
+MAIN
+    end
+  end
+end