fix all tests to use space.main

test/register/interpreter/test_add.rb

@@ -5,7 +5,7 @@ class AddTest < MiniTest::Test
 
   def setup
     @string_input = <<HERE
-class Object
+class Space
   int main()
     return 5 + 7
   end

test/register/interpreter/test_if.rb

@@ -5,7 +5,7 @@ class IfTest < MiniTest::Test
 
   def setup
     @string_input = <<HERE
-class Object
+class Space
   int itest(int n)
     if_zero( n - 12)
       "then".putstring()

test/register/interpreter/test_mult.rb

@@ -6,7 +6,7 @@ class MultTest < MiniTest::Test
 
   def setup
     @string_input = <<HERE
-class Object
+class Space
   int main()
     return #{2**31} * #{2**31}
   end

test/register/interpreter/test_plus.rb

@@ -5,7 +5,7 @@ class PlusTest < MiniTest::Test
 
   def setup
     @string_input = <<HERE
-class Object
+class Space
   int main()
     return #{2**62 - 1} + 1
   end

test/register/interpreter/test_puts.rb

@@ -5,7 +5,7 @@ class TestPuts < MiniTest::Test
 
   def setup
       @string_input = <<HERE
-class Object
+class Space
   int main()
     "Hello again".putstring()
   end