correct flattening for moms if

lib/mom/if_statement.rb

@@ -11,7 +11,17 @@ module Mom
     end
 
     def flatten
-      self
+      head = hoisted.flatten
+      true_label = Label.new( "true_label_#{object_id}")
+      false_label = Label.new( "false_label_#{object_id}")
+      merge_label = Label.new( "merge_label_#{object_id}")
+      head.append condition.flatten( true_label: true_label , false_label: false_label)
+      head.append true_label
+      head.append if_true.flatten( merge_label: merge_label)
+      head.append false_label
+      head.append if_false.flatten( merge_label: merge_label)
+      head.append merge_label
+      head
     end
   end
 

lib/mom/statement.rb

@@ -1,7 +1,7 @@
 module Mom
   class Statement
     # flattening will change the structure from a tree to a linked list (and use
-    # next_instruction to do so)
+    # nekst to do so)
     def flatten
       raise "not implemented for #{self}"
     end
@@ -10,9 +10,14 @@ module Mom
   class Statements < Statement
     include Common::Statements
 
-    def flatten
+    def flatten( options = {}  )
-      @statements.each{ |s| s.flatten }
+      flat = @statements.pop.flatten
+      while( nekst = @statements.pop )
+        flat.append nekst.flatten()
+      end
+      flat
     end
+
   end
 
 end

test/mom/test_if_simple.rb

@@ -0,0 +1,27 @@
+
+require_relative "helper"
+
+module Mom
+  class TestConditionIfMom < MiniTest::Test
+    include MomCompile
+
+    def setup
+      Risc.machine.boot
+      @stats = compile_first_method_flat( "if(@a == 5)  ; 5.mod4 ; else; 4.mod4 ; end")
+      @first = @stats.next
+    end
+
+    def test_if_compiles
+      assert IfStatement != @stats.class , @stats
+    end
+    def test_check
+      assert_equal TruthCheck , @first.class
+    end
+    def test_condition_is_slot
+      assert_equal SlotDefinition , @first.condition.class , @first
+    end
+    def test_length
+      assert_equal 9 , @stats.length
+    end
+  end
+end