start on insertion events and handling

lib/arm/instructions/instruction.rb

@@ -22,10 +22,9 @@ module Arm
     end
 
     def insert(instruction)
-      super
-      my_pos = Risc::Position.get(self)
-      listener = Risc::InstructionListener.new( instruction , my_pos.get_code )
-      my_pos.position_listener(listener)
+      ret = super
+      Risc::Position.get(self).trigger_inserted if Risc::Position.set?(self)
+      ret
     end
   end
 end

lib/risc/position/instruction_listener.rb

@@ -19,6 +19,10 @@ module Risc
       @binary = binary
     end
 
+    # if the position of the instruction before us changes, we need to
+    # adjust the position of this instruction accordingly
+    # Taking into account that BinaryCodes only take 13 instructions,
+    # meaning that chain may have to be extended
     def position_changed(position)
       fix_binary
       my_pos = Position.get(@instruction)
@@ -34,6 +38,32 @@ module Risc
       my_pos.set(next_pos)
     end
 
+    # When this is called, only the actual insert has happened (keeping the
+    # position logic out of the instruction assembly).
+    #
+    # This event happens at the listener that was dependent on the position
+    # before the insert, ie:
+    # position : the arg is the first instruction in the chain where insert happened
+    # position.object.next : is the newly inserted instruction we need to setup
+    # @instruction : previously dependent on position, now on .next's position
+    #
+    # So we need to :
+    # - move the listener of @instruction to listen to the inserted instruction
+    # - add a listener for the new instruction (to listen to the arg)
+    # - set the new position (moving the chain along)
+    def position_inserted(position)
+      inserted = position.object.next
+      raise "uups" unless inserted ## TODO: remove
+      position.remove_position_listener(InstructionListener)
+      new_pos = Position.get(inserted)
+      new_pos.position_listener(old_listener)
+
+      my_pos = Position.get(@instruction)
+      listen = InstructionListener.new(position.object , @binary)
+      my_pos.position_listener(listen)
+
+    end
+
     # check that the binary we use is the one where the current position falls
     # if not move up and register/unregister (soon)
     def fix_binary

lib/risc/position/position.rb

@@ -43,6 +43,11 @@ module Risc
       register_event(:position_changed , listener)
     end
 
+    # When instruction get inserted, we have to move listeners around, remove given
+    def remove_position_listener(list)
+      unregister_event(:position_changed, list)
+    end
+
     # utility to get all registered listeners to the :position_changed event
     # returns an array
     def position_listeners
@@ -68,6 +73,10 @@ module Risc
       int
     end
 
+    def trigger_inserted
+      event_table[:position_changed].each { |handler| handler.position_inserted( self) }
+    end
+
     def +(offset)
       offset = offset.at if offset.is_a?(Position)
       @at + offset

test/risc/position/helper.rb

@@ -14,5 +14,10 @@ module Risc
     def initialize(nekst = nil)
       @next = nekst
     end
+    def insert(instruction)
+      ret = super
+      Position.get(self).trigger_inserted if Position.set?(self)
+      ret
+    end
   end
 end

test/risc/position/test_instruction_listener.rb

@@ -53,24 +53,4 @@ module Risc
       assert_equal Branch , at_8.object.class
     end
   end
-  class TestInstructionListenerBig < MiniTest::Test
-    def setup
-      Risc.machine.boot
-      @binary = Parfait::BinaryCode.new(1)
-      @bin_pos = Position.new(@binary,0)
-      @instruction = DummyInstruction.new
-      13.times {@instruction.last.insert(DummyInstruction.new) }
-      @position = InstructionListener.init(@instruction , @binary)
-      @position.set(8)
-    end
-    def test_padding
-      assert_equal 64 , @binary.padded_length
-    end
-    def test_last
-      assert_equal 72 , Position.get(@instruction.last).at
-    end
-    def test_next
-      assert @binary.next
-    end
-  end
 end

test/risc/position/test_instruction_listener1.rb

@@ -0,0 +1,32 @@
+require_relative "helper"
+
+module Risc
+  class TestInstructionListenerBig < MiniTest::Test
+    def setup
+      Risc.machine.boot
+      @binary = Parfait::BinaryCode.new(1)
+      @bin_pos = Position.new(@binary,0)
+      @instruction = DummyInstruction.new
+      13.times {@instruction.last.insert(DummyInstruction.new) }
+      @position = InstructionListener.init(@instruction , @binary)
+      @position.set(8)
+    end
+    def test_padding
+      assert_equal 64 , @binary.padded_length
+    end
+    def test_last
+      assert_equal 72 , Position.get(@instruction.last).at
+    end
+    def test_next
+      assert @binary.next
+    end
+    def test_insert_initializes
+      @instruction.insert DummyInstruction.new
+      assert Position.get(@instruction.next)
+    end
+    def pest_insert_pushes
+      @instruction.insert DummyInstruction.new
+      assert_equal 76 , Position.get(@instruction.last).at
+    end
+  end
+end

test/risc/position/test_position.rb

@@ -24,6 +24,9 @@ module Risc
     def test_has_listeners_helper
       assert_equal Array , @pos.position_listeners.class
     end
+    def test_has_trigger_inserted
+      assert_equal [] , @pos.trigger_inserted
+    end
     def test_listeners_empty
       assert @pos.position_listeners.empty?
     end
@@ -80,7 +83,7 @@ module Risc
     def test_can_unregister
       listener = PositionListener.new(self)
       assert @position.position_listener(listener)
-      assert @position.unregister_event(:position_changed ,listener)
+      assert @position.remove_position_listener(listener)
     end
     def test_fires
       @object = @instruction
@@ -92,13 +95,22 @@ module Risc
       @object = @instruction
       Position.new(self, 10)
       assert @position.register_event(:position_changed , self)
-      assert @position.unregister_event(:position_changed ,self)
+      assert @position.remove_position_listener(self)
       @position.trigger(:position_changed , @position)
       assert_nil @trigger
     end
+    def test_can_trigger_inserted
+      @object = @instruction
+      @position.register_event(:position_changed , self)
+      @position.trigger_inserted
+      assert_equal @position , @trigger
+    end
     def position_changed(pos)
       @trigger = pos
     end
+    def position_inserted(pos)
+      @trigger = pos
+    end
   end
 end