Prune invalid recipes

src/client/models/crafting/crafting_node.coffee

@@ -57,6 +57,12 @@ module.exports = class CraftingNode
             leave = visitor['onLeaveOtherNode']
             if leave? then leave.call visitor, this
 
+    pruneInvalidChildren: ->
+        @_pruneInvalidChildren()
+
+    removeChild: (index)->
+        @_children.splice index, 1
+
     rotateChildren: ->
         @_children.push @_children.shift()
         @_rotations += 1
@@ -120,3 +126,9 @@ module.exports = class CraftingNode
     # explored for having a useful crafting plan.
     _checkValidity: ->
         throw new Error "#{@constructor.name} must override the _checkValidity method"
+
+    # Subclasses may override this method to remove any children determined to be invalid and therefore unable to be
+    # of any use in finding legitimate crafting plans.
+    _pruneInvalidChildren: ->
+        for child in @children
+            child.pruneInvalidChildren()

src/client/models/crafting/craftsman.coffee

@@ -80,7 +80,9 @@ module.exports = class Craftsman extends BaseModel
             @stageCount = 0
             logger.warning => "Craftsman could not complete a crafting plan."
         else if not @_planBuilder?
+            @_graphBuilder.pruneInvalidNodes()
             logger.debug => "Craftsman finished computing graph:\n#{@_graphBuilder.rootNode}"
+
             @_planBuilder = new PlanBuilder @_graphBuilder.rootNode, @_modPack, have:@_have, want:@_want
             @stage        = @STAGE.PLANNING
             @stageCount   = 0

src/client/models/crafting/graph_builder.coffee

@@ -40,6 +40,9 @@ module.exports = class GraphBuilder
             node.expand @_queue
             @_stepCount += 1
 
+    pruneInvalidNodes: ->
+        @_rootNode.pruneInvalidChildren()
+
     reset: ->
 
     # Property Methods #############################################################################

src/client/models/crafting/item_node.coffee

@@ -74,6 +74,16 @@ module.exports = class ItemNode extends CraftingNode
             return true if child.valid
         return false
 
+    _pruneInvalidChildren: ->
+        index = 0
+        while index < @children.length
+            child = @children[index]
+            if child.valid
+                child.pruneInvalidChildren()
+                index++
+            else
+                @removeChild index
+
     # Object Overrides #############################################################################
 
     toString: (options={})->