text: ##########################################################################
  #
  #  Copyright (c) 2011-2012, John Haddon. All rights reserved.
  #  Copyright (c) 2011-2013, Image Engine Design Inc. All rights reserved.
  #
  #  Redistribution and use in source and binary forms, with or without
  #  modification, are permitted provided that the following conditions are
  #  met:
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  #      * Redistributions of source code must retain the above
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  #        disclaimer.
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  #        copyright notice, this list of conditions and the following
  #        disclaimer in the documentation and/or other materials provided with
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  #  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  #  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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  ##########################################################################
  
  import unittest
  import sys
  import weakref
  import gc
  import os
  import shutil
  import stat
  import inspect
  import functools
  import six
  import imath
  
  import IECore
  
  import Gaffer
  import GafferTest
  
  class ScriptNodeTest( GafferTest.TestCase ) :
  
  	def setUp( self ) :
  
  		GafferTest.TestCase.setUp( self )
  
  		ScriptNodeTest.lastNode = None
  		ScriptNodeTest.lastScript = None
  		ScriptNodeTest.lastResult = None
  
  	def test( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertEqual( s.getName(), "ScriptNode" )
  
  		self.assertEqual( s["fileName"].typeName(), "Gaffer::StringPlug" )
  
  	def testExecution( self ) :
  
  		s = Gaffer.ScriptNode()
  		s.execute( "script.addChild( Gaffer.Node( 'child' ) )" )
  		self.assertEqual( s["child"].typeName(), "Gaffer::Node" )
  
  	def testSelection( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertIsInstance( s.selection(), Gaffer.Set )
  
  		n = Gaffer.Node()
  
  		self.assertRaises( Exception, s.selection().add, n )
  
  		s.addChild( n )
  
  		s.selection().add( n )
  
  		self.assertIn( n, s.selection() )
  
  		s.removeChild( n )
  
  		self.assertNotIn( n, s.selection() )
  
  	def testSerialisation( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["a1"] = GafferTest.AddNode()
  		s["a1"]["op1"].setValue( 5 )
  		s["a1"]["op2"].setValue( 6 )
  
  		s["a2"] = GafferTest.AddNode()
  		s["a2"]["op1"].setInput( s["a1"]["sum"] )
  		s["a2"]["op2"].setValue( 10 )
  
  		s2 = Gaffer.ScriptNode()
  		se = s.serialise()
  
  		s2.execute( se )
  
  		self.assertTrue( s2["a2"]["op1"].getInput().isSame( s2["a1"]["sum"] ) )
  
  	def testDynamicPlugSerialisation( self ) :
  
  		s1 = Gaffer.ScriptNode()
  
  		s1["n1"] = GafferTest.AddNode()
  		s1["n2"] = GafferTest.AddNode()
  		s1["n1"]["dynamicPlug"] = Gaffer.IntPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s1["n1"]["dynamicPlug"].setInput( s1["n2"]["sum"] )
  		s1["n1"]["dynamicPlug2"] = Gaffer.IntPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s1["n1"]["dynamicPlug2"].setValue( 100 )
  		s1["n1"]["dynamicStringPlug"] = Gaffer.StringPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s1["n1"]["dynamicStringPlug"].setValue( "hiThere" )
  		s1["n1"]["dynamicOutPlug"] = Gaffer.IntPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic, direction=Gaffer.Plug.Direction.Out )
  		s1["n1"]["dynamicColorOutPlug"] = Gaffer.Color3fPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic, direction=Gaffer.Plug.Direction.Out )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s1.serialise() )
  
  		self.assertTrue( s2["n1"]["dynamicPlug"].getInput().isSame( s2["n2"]["sum"] ) )
  		self.assertEqual( s2["n1"]["dynamicPlug2"].getValue(), 100 )
  		self.assertEqual( s2["n1"]["dynamicStringPlug"].getValue(), "hiThere" )
  		self.assertIsInstance( s2["n1"]["dynamicOutPlug"], Gaffer.IntPlug )
  		self.assertIsInstance( s2["n1"]["dynamicColorOutPlug"], Gaffer.Color3fPlug )
  
  	def testLifetime( self ) :
  
  		s = Gaffer.ScriptNode()
  		w = weakref.ref( s )
  		del s
  		IECore.RefCounted.collectGarbage()
  
  		self.assertEqual( w(), None )
  
  	def testSaveAndLoad( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["a1"] = GafferTest.AddNode()
  		s["a2"] = GafferTest.AddNode()
  
  		s["a1"]["op1"].setValue( 5 )
  		s["a1"]["op2"].setValue( 6 )
  
  		s["a2"] = GafferTest.AddNode()
  		s["a2"]["op1"].setInput( s["a1"]["sum"] )
  		s["a2"]["op2"].setValue( 10 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertTrue( s2["a2"]["op1"].getInput().isSame( s2["a1"]["sum"] ) )
  
  	def testLoadClearsFirst( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["a1"] = GafferTest.AddNode()
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s.load()
  		self.assertNotIn( "a2", s )
  
  	def testSaveFailureHandling( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["a1"] = GafferTest.AddNode()
  
  		s["fileName"].setValue( "/this/directory/doesnt/exist" )
  		self.assertRaises( Exception, s.save )
  
  	def testLoadFailureHandling( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["fileName"].setValue( "/this/file/doesnt/exist" )
  		self.assertRaises( Exception, s.load )
  
  	def testCopyPaste( self ) :
  
  		app = Gaffer.ApplicationRoot()
  
  		s1 = Gaffer.ScriptNode()
  		s2 = Gaffer.ScriptNode()
  
  		app["scripts"]["s1"] = s1
  		app["scripts"]["s2"] = s2
  
  		n1 = GafferTest.AddNode()
  		s1["n1"] = n1
  
  		s1.copy()
  
  		s2.paste()
  
  		self.assertTrue( s1["n1"].isInstanceOf( GafferTest.AddNode.staticTypeId() ) )
  		self.assertTrue( s2["n1"].isInstanceOf( GafferTest.AddNode.staticTypeId() ) )
  
  	def testSerialisationWithKeywords( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n1"] = GafferTest.KeywordPlugNode()
  
  		se = s.serialise()
  		s2 = Gaffer.ScriptNode()
  		s2.execute( se )
  
  	def testSerialisationWithNodeKeywords( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["in"] = Gaffer.Node()
  
  		se = s.serialise()
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( se )
  
  		self.assertEqual( s2["in"].typeName(), "Gaffer::Node" )
  
  	def testDeriveAndOverrideAcceptsChild( self ) :
  
  		class MyScriptNode( Gaffer.ScriptNode ) :
  
  			def __init__( self, name ) :
  
  				Gaffer.ScriptNode.__init__( self, name )
  
  			def acceptsChild( self, child ) :
  
  				return isinstance( child, GafferTest.AddNode )
  
  		IECore.registerRunTimeTyped( MyScriptNode )
  
  		n = MyScriptNode( "s" )
  
  		c1 = GafferTest.AddNode()
  		c2 = Gaffer.Node()
  
  		n.addChild( c1 )
  		self.assertTrue( c1.parent() is n )
  		self.assertTrue( c1.scriptNode() is n )
  
  		self.assertRaises( RuntimeError, n.addChild, c2 )
  		self.assertIsNone( c2.parent() )
  
  	def testExecutionExceptions( self ) :
  
  		n = Gaffer.ScriptNode()
  
  		self.assertRaises( RuntimeError, n.execute, "raise ValueError" )
  
  	def testVariableScope( self ) :
  
  		# if a variable gets made in one execution, it shouldn't persist in the next.
  
  		n = Gaffer.ScriptNode()
  
  		n.execute( "a = 10" )
  		six.assertRaisesRegex( self, Exception, "NameError: name 'a' is not defined", n.execute, "a * 10" )
  
  	def testClassScope( self ) :
  
  		# this works in a normal python console, so it damn well better work
  		# in a script editor.
  
  		s = inspect.cleandoc(
  			"""
  			class A() :
  
  				def __init__( self ) :
  
  					print( A )
  
  			a = A()
  			"""
  		)
  
  		n = Gaffer.ScriptNode()
  		n.execute( s )
  
  	def testDeselectionOnDelete( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		n1 = GafferTest.AddNode()
  		n2 = GafferTest.AddNode()
  
  		s["n1"] = n1
  		s["n2"] = n2
  
  		s.selection().add( n1 )
  		self.assertIn( n1, s.selection() )
  
  		del s["n1"]
  
  		self.assertNotIn( n1, s.selection() )
  
  	def testContext( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		c = s.context()
  		c.setFrame( 10.0 )
  
  		self.assertEqual( s.context().getFrame(), 10.0 )
  		self.assertTrue( s.context().isSame( c ) )
  
  	def testFrameRange( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		self.assertIsInstance( s["frameRange"]["start"], Gaffer.IntPlug )
  		self.assertIsInstance( s["frameRange"]["end"], Gaffer.IntPlug )
  
  		self.assertEqual( s["frameRange"]["start"].getValue(), 1 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 100 )
  
  		s["frameRange"]["start"].setValue( 110 )
  		self.assertEqual( s["frameRange"]["start"].getValue(), 110 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 110 )
  
  		s["frameRange"]["end"].setValue( 200 )
  		self.assertEqual( s["frameRange"]["start"].getValue(), 110 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 200 )
  
  		s["frameRange"]["end"].setValue( 100 )
  		self.assertEqual( s["frameRange"]["start"].getValue(), 100 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 100 )
  
  	def testFrameRangeLoadAndSave( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["frameRange"]["start"].setValue( 110 )
  		s["frameRange"]["end"].setValue( 200 )
  		self.assertEqual( s["frameRange"]["start"].getValue(), 110 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 200 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( s2["frameRange"]["start"].getValue(), 110 )
  		self.assertEqual( s2["frameRange"]["end"].getValue(), 200 )
  
  	def testApplicationRoot( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertIsNone( s.applicationRoot() )
  
  		a = Gaffer.ApplicationRoot()
  		a["scripts"]["one"] = s
  
  		self.assertTrue( s.applicationRoot().isSame( a ) )
  
  	def testLifeTimeAfterExecution( self ) :
  
  		# the ScriptNode used to keep an internal dictionary
  		# as the context for all script execution. this created the
  		# danger of circular references keeping it alive forever.
  		# that is no longer the case, but this test remains to ensure
  		# that the same problem doesn't crop up in the future.
  
  		a = Gaffer.ApplicationRoot()
  		a["scripts"]["s"] = Gaffer.ScriptNode()
  
  		a["scripts"]["s"].execute( "script.addChild( Gaffer.Node( \"a\" ) )" )
  		a["scripts"]["s"].execute( "circularRef = script.getChild( \"a\" ).parent()" )
  
  		w = weakref.ref( a["scripts"]["s"] )
  
  		del a["scripts"]["s"]
  		IECore.RefCounted.collectGarbage()
  
  		self.assertEqual( w(), None )
  
  	def testDeleteNodes( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = Gaffer.Node()
  		s["n1"] = Gaffer.Node()
  		s["n2"] = Gaffer.Node()
  		self.assertEqual( len( s.children( Gaffer.Node ) ), 3 )
  
  		s.deleteNodes()
  		self.assertEqual( len( s.children( Gaffer.Node ) ), 0 )
  
  	def testDeleteManyNodes( self ) :
  
  		s = Gaffer.ScriptNode()
  		for i in range( 0, 10000 ) :
  			s["c%d"%i] = Gaffer.Node()
  
  		s.deleteNodes()
  
  		self.assertEqual( len( s.children( Gaffer.Node ) ), 0 )
  
  	def testDeleteNodesDoesntRemovePlugs( self ) :
  
  		s = Gaffer.ScriptNode()
  		s.deleteNodes()
  
  		self.assertIn( "fileName", s )
  
  	def testDeleteNodesWithFilter( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = Gaffer.Node()
  		s["n1"] = Gaffer.Node()
  		s["n2"] = Gaffer.Node()
  		self.assertEqual( len( s.children( Gaffer.Node ) ), 3 )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ s["n1"] ] ) )
  		self.assertEqual( len( s.children( Gaffer.Node ) ), 2 )
  		self.assertIn( "n", s )
  		self.assertNotIn( "n1", s )
  		self.assertIn( "n2", s )
  
  	def testDeleteNodesMaintainsConnections( self ) :
  
  		s = Gaffer.ScriptNode()
  		n1 = GafferTest.AddNode()
  		n2 = GafferTest.MultiplyNode()
  		n3 = GafferTest.AddNode()
  		n4 = GafferTest.AddNode()
  
  		s.addChild( n1 )
  		s.addChild( n2 )
  		s.addChild( n3 )
  		s.addChild( n4 )
  
  		n2["op1"].setInput( n1["sum"] )
  		n2["op2"].setInput( n1["sum"] )
  		n3["op1"].setInput( n1["sum"] )
  		n3["op2"].setInput( n1["sum"] )
  		n4["op1"].setInput( n2["product"] )
  		n4["op2"].setInput( n3["sum"] )
  		self.assertTrue( n2["op1"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n2["op2"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n3["op1"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n3["op2"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n4["op1"].getInput().isSame( n2["product"] ) )
  		self.assertTrue( n4["op2"].getInput().isSame( n3["sum"] ) )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ n2, n3 ] ) )
  
  		self.assertEqual( n2["op1"].getInput(), None )
  		self.assertEqual( n2["op2"].getInput(), None )
  		self.assertEqual( n3["op1"].getInput(), None )
  		self.assertEqual( n3["op2"].getInput(), None )
  		# None because MultiplyOp does not define enabledPlug()
  		self.assertEqual( n4["op1"].getInput(), None )
  		self.assertTrue( n4["op2"].getInput().isSame( n1["sum"] ) )
  
  		n2["op1"].setInput( n1["sum"] )
  		n2["op2"].setInput( n1["sum"] )
  		n3["op1"].setInput( n1["sum"] )
  		n3["op2"].setInput( n1["sum"] )
  		n4["op1"].setInput( n2["product"] )
  		n4["op2"].setInput( n3["sum"] )
  		s.addChild( n2 )
  		s.addChild( n3 )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ n2, n3 ] ), reconnect = False )
  
  		self.assertEqual( n2["op1"].getInput(), None )
  		self.assertEqual( n2["op2"].getInput(), None )
  		self.assertEqual( n3["op1"].getInput(), None )
  		self.assertEqual( n3["op2"].getInput(), None )
  		self.assertEqual( n4["op1"].getInput(), None )
  		self.assertEqual( n4["op2"].getInput(), None )
  
  	def testDeleteNodesWithEnabledPlugsWithoutCorrespondingInput( self ) :
  
  		class MyAddNode( GafferTest.AddNode ) :
  
  			def correspondingInput( self, output ) :
  
  				return None
  
  		s = Gaffer.ScriptNode()
  		n1 = GafferTest.AddNode()
  		n2 = MyAddNode()
  		n3 = GafferTest.AddNode()
  
  		s.addChild( n1 )
  		s.addChild( n2 )
  		s.addChild( n3 )
  
  		n2["op1"].setInput( n1["sum"] )
  		n2["op2"].setInput( n1["sum"] )
  		n3["op1"].setInput( n2["sum"] )
  		n3["op2"].setInput( n2["sum"] )
  		self.assertTrue( n2["op1"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n2["op2"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n3["op1"].getInput().isSame( n2["sum"] ) )
  		self.assertTrue( n3["op2"].getInput().isSame( n2["sum"] ) )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ n2 ] ) )
  
  		self.assertEqual( n2["op1"].getInput(), None )
  		self.assertEqual( n2["op2"].getInput(), None )
  		self.assertEqual( n3["op1"].getInput(), None )
  		self.assertEqual( n3["op2"].getInput(), None )
  
  	def testReconnectionToFloatingNodes( self ) :
  
  		s = Gaffer.ScriptNode()
  		n1 = GafferTest.AddNode()
  		n2 = GafferTest.AddNode()
  		n3 = GafferTest.AddNode()
  
  		s.addChild( n1 )
  		s.addChild( n2 )
  
  		n2["op1"].setInput( n1["sum"] )
  		n2["op2"].setInput( n1["sum"] )
  
  		n3["op1"].setInput( n2["sum"] )
  		n3["op2"].setInput( n2["sum"] )
  
  		self.assertTrue( n2["op1"].getInput().isSame( n1["sum"] ) )
  		self.assertTrue( n2["op2"].getInput().isSame( n1["sum"] ) )
  
  		self.assertTrue( n3["op1"].getInput().isSame( n2["sum"] ) )
  		self.assertTrue( n3["op2"].getInput().isSame( n2["sum"] ) )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ n2 ] ) )
  
  		# the inputs to n3 shouldn't have been reconnected, as it's not a descendant of the script:
  		self.assertEqual( n3["op1"].getInput(), None )
  		self.assertEqual( n3["op2"].getInput(), None )
  
  	def testDynamicPlugSaveAndLoad( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["customSetting"] = Gaffer.IntPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["customSetting"].setValue( 100 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( s2["customSetting"].getValue(), 100 )
  
  	def testSerialiseCircularConnections( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["n1"] = Gaffer.Node()
  		s["n2"] = Gaffer.Node()
  
  		s["n1"]["in"] = Gaffer.Plug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["n1"]["out"] = Gaffer.Plug( direction = Gaffer.Plug.Direction.Out,  flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  
  		s["n2"]["in"] = Gaffer.Plug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["n2"]["out"] = Gaffer.Plug( direction = Gaffer.Plug.Direction.Out, flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  
  		s["n1"]["in"].setInput( s["n2"]["out"] )
  		s["n2"]["in"].setInput( s["n1"]["out"] )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise() )
  
  		self.assertTrue( s2["n1"]["in"].getInput().isSame( s2["n2"]["out"] ) )
  		self.assertTrue( s2["n2"]["in"].getInput().isSame( s2["n1"]["out"] ) )
  
  	def testSerialiseWithFilter( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  
  		s["n2"]["op1"].setInput( s["n1"]["sum"] )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise( filter = Gaffer.StandardSet( [ s["n2"] ] ) ) )
  
  		self.assertTrue( "n2" in s2 )
  		self.assertTrue( "n1" not in s2 )
  
  		self.assertEqual( s2["n2"]["op1"].getInput(), None )
  
  	def testCopyIgnoresNestedSelections( self ) :
  
  		a = Gaffer.ApplicationRoot()
  		s = Gaffer.ScriptNode()
  		a["scripts"].addChild( s )
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["b"] = Gaffer.Box()
  		s["b"]["n1"] = GafferTest.AddNode()
  
  		s.selection().add( s["n1"] )
  		s.selection().add( s["b"]["n1"] )
  		s.copy( filter = s.selection() )
  
  		s2 = Gaffer.ScriptNode()
  		a["scripts"].addChild( s2 )
  		s2.paste()
  
  		self.assertTrue( "n1" in s2 )
  		self.assertTrue( "b" not in s2 )
  
  		s.selection().clear()
  		s.selection().add( s["b"]["n1"] )
  		s.copy( filter = s.selection() )
  
  		s2 = Gaffer.ScriptNode()
  		a["scripts"].addChild( s2 )
  		s2.paste()
  
  		self.assertTrue( "b" not in s2 )
  		self.assertTrue( "n1" not in s2 )
  
  	def testCopyPasteWithSpecificSourceParent( self ) :
  
  		a = Gaffer.ApplicationRoot()
  		s = Gaffer.ScriptNode()
  		a["scripts"].addChild( s )
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["b"] = Gaffer.Box()
  		s["b"]["n3"] = GafferTest.AddNode()
  		s["b"]["n4"] = GafferTest.AddNode()
  
  		s.selection().add( s["n1"] )
  		s.selection().add( s["b"]["n3"] )
  
  		s.copy( parent=s["b"], filter = s.selection() )
  
  		s2 = Gaffer.ScriptNode()
  		a["scripts"].addChild( s2 )
  		s2.paste()
  
  		self.assertTrue( "n1" not in s2 )
  		self.assertTrue( "n2" not in s2 )
  		self.assertTrue( "b" not in s2 )
  		self.assertTrue( "n3" in s2 )
  		self.assertTrue( "n4" not in s2 )
  
  	def testCopyPasteWithSpecificDestinationParent( self ) :
  
  		a = Gaffer.ApplicationRoot()
  		s = Gaffer.ScriptNode()
  		a["scripts"].addChild( s )
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  
  		s.selection().add( s["n1"] )
  		s.copy( filter = s.selection() )
  
  		s2 = Gaffer.ScriptNode()
  		a["scripts"].addChild( s2 )
  		s2["b"] = Gaffer.Box()
  		s2.paste( parent = s2["b"] )
  
  		self.assertTrue( "n1" not in s2 )
  		self.assertTrue( "n2" not in s2 )
  		self.assertTrue( "n1" in s2["b"] )
  		self.assertTrue( "n2" not in s2["b"] )
  
  		self.assertEqual( len( s2.selection() ), 1 )
  		self.assertTrue( s2["b"]["n1"] in s2.selection() )
  
  	def testCutWithSpecificSourceParent( self ) :
  
  		a = Gaffer.ApplicationRoot()
  		s = Gaffer.ScriptNode()
  		a["scripts"].addChild( s )
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["b"] = Gaffer.Box()
  		s["b"]["n3"] = GafferTest.AddNode()
  		s["b"]["n4"] = GafferTest.AddNode()
  
  		s.selection().add( s["n1"] )
  		s.selection().add( s["b"]["n3"] )
  
  		s.cut( parent=s["b"], filter = s.selection() )
  		self.assertTrue( "n1" in s )
  		self.assertTrue( "n2" in s )
  		self.assertTrue( "b" in s )
  		self.assertTrue( "n3" not in s["b"] )
  		self.assertTrue( "n4" in s["b"] )
  
  		s2 = Gaffer.ScriptNode()
  		a["scripts"].addChild( s2 )
  		s2.paste()
  
  		self.assertTrue( "n1" not in s2 )
  		self.assertTrue( "n2" not in s2 )
  		self.assertTrue( "b" not in s2 )
  		self.assertTrue( "n3" in s2 )
  		self.assertTrue( "n4" not in s2 )
  
  	def testActionSignal( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		cs = GafferTest.CapturingSlot( s.actionSignal() )
  
  		# shouldn't trigger anything, because it's not in an undo scope
  		s.addChild( Gaffer.Node() )
  		self.assertEqual( len( cs ), 0 )
  
  		# should trigger something, because it's in an undo scope
  		with Gaffer.UndoScope( s ) :
  			s.addChild( Gaffer.Node( "a" ) )
  
  		self.assertEqual( len( cs ), 1 )
  		self.assertTrue( cs[0][0].isSame( s ) )
  		self.assertTrue( isinstance( cs[0][1], Gaffer.Action ) )
  		self.assertEqual( cs[0][2], Gaffer.Action.Stage.Do )
  
  		# undo should trigger as well
  		s.undo()
  
  		self.assertEqual( len( cs ), 2 )
  		self.assertTrue( cs[1][0].isSame( s ) )
  		self.assertTrue( cs[1][1].isSame( cs[0][1] ) )
  		self.assertEqual( cs[1][2], Gaffer.Action.Stage.Undo )
  
  		# as should redo
  		s.redo()
  
  		self.assertEqual( len( cs ), 3 )
  		self.assertTrue( cs[2][0].isSame( s ) )
  		self.assertTrue( cs[2][1].isSame( cs[0][1] ) )
  		self.assertEqual( cs[2][2], Gaffer.Action.Stage.Redo )
  
  	def testLoadingMovedScriptDoesntKeepOldFileName( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = Gaffer.Node()
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		shutil.move( self.temporaryDirectory() + "/test.gfr", self.temporaryDirectory() + "/test2.gfr" )
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( self.temporaryDirectory() + "/test2.gfr" )
  		s.load()
  
  		self.assertEqual( s["fileName"].getValue(), self.temporaryDirectory() + "/test2.gfr" )
  
  	def testUnsavedChanges( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		# the unsaved changes flag only reacts to undoable changes
  		# so this shouldn't set the flag
  		s["nonUndoableNode"] = GafferTest.AddNode()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		# but this should.
  		with Gaffer.UndoScope( s ) :
  			s["node"] = GafferTest.AddNode()
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		with Gaffer.UndoScope( s ) :
  			s["node"]["op1"].setValue( 10 )
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		with Gaffer.UndoScope( s ) :
  			s["node"]["op1"].setValue( 20 )
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		s.undo()
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		s.redo()
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		with Gaffer.UndoScope( s ) :
  			s["node2"] = GafferTest.AddNode()
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		with Gaffer.UndoScope( s ) :
  			s["node2"]["op1"].setInput( s["node"]["sum"] )
  		self.assertEqual( s["unsavedChanges"].getValue(), True )
  
  		s.save()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  		s.load()
  		self.assertEqual( s["unsavedChanges"].getValue(), False )
  
  	def testSerialiseToFile( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["n2"]["op1"].setInput( s["n1"]["sum"] )
  
  		s.serialiseToFile( self.temporaryDirectory() + "/test.gfr" )
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertTrue( "n1" in s2 )
  		self.assertTrue( "n2" in s2 )
  		self.assertTrue( s2["n2"]["op1"].getInput().isSame( s2["n1"]["sum"] ) )
  
  		s.serialiseToFile( self.temporaryDirectory() + "/test.gfr", filter = Gaffer.StandardSet( [ s["n2"] ] ) )
  
  		s3 = Gaffer.ScriptNode()
  		s3["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s3.load()
  
  		self.assertTrue( "n1" not in s3 )
  		self.assertTrue( "n2" in s3 )
  
  	def testExecuteFile( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["n2"]["op1"].setInput( s["n1"]["sum"] )
  
  		s.serialiseToFile( self.temporaryDirectory() + "/test.gfr" )
  
  		s2 = Gaffer.ScriptNode()
  
  		self.assertRaises( RuntimeError, s2.executeFile, "thisFileDoesntExist.gfr" )
  
  		s2.executeFile( self.temporaryDirectory() + "/test.gfr" )
  
  		self.assertTrue( s2["n2"]["op1"].getInput().isSame( s2["n1"]["sum"] ) )
  
  	def testUndoAndRedoOrder( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = Gaffer.Node()
  		s["n"]["p"] = Gaffer.IntPlug()
  
  		values = []
  		def f( plug ) :
  			values.append( plug.getValue() )
  
  		c = s["n"].plugSetSignal().connect( f )
  
  		with Gaffer.UndoScope( s ) :
  			s["n"]["p"].setValue( 10 )
  			s["n"]["p"].setValue( 20 )
  
  		self.assertEqual( values, [ 10, 20 ] )
  
  		s.undo()
  		self.assertEqual( values, [ 10, 20, 10, 0 ] )
  
  		s.redo()
  		self.assertEqual( values, [ 10, 20, 10, 0, 10, 20 ] )
  
  	def testUndoAddedSignal( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		cs = GafferTest.CapturingSlot( s.undoAddedSignal() )
  
  		s["n"] = Gaffer.Node()
  		self.assertEqual( cs, [] )
  
  		with Gaffer.UndoScope( s ) :
  			s["n"]["p"] = Gaffer.IntPlug( flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  			s["n"]["p"].setValue( 100 )
  
  		self.assertEqual( len( cs ), 1 )
  		self.assertTrue( cs[0][0].isSame( s ) )
  
  		with Gaffer.UndoScope( s, mergeGroup = "test" ) :
  			s["n"]["p"].setValue( 200 )
  
  		self.assertEqual( len( cs ), 2 )
  		self.assertTrue( cs[1][0].isSame( s ) )
  
  		with Gaffer.UndoScope( s, mergeGroup = "test" ) :
  			s["n"]["p"].setValue( 300 )
  
  		# undo was merged, so a new one wasn't added
  		self.assertEqual( len( cs ), 2 )
  		self.assertTrue( cs[1][0].isSame( s ) )
  
  	def testCustomVariables( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "test", IECore.IntData( 10 ), flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context().get( "test" ), 10 )
  		p["value"].setValue( 20 )
  		self.assertEqual( s.context().get( "test" ), 20 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( s2["variables"][p.getName()]["value"].getValue(), 20 )
  		self.assertEqual( s2.context().get( "test" ), 20 )
  
  	def testFileNameVariables( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertEqual( s.context().get( "script:name" ), "" )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		self.assertEqual( s.context().get( "script:name" ), "test" )
  
  	def testReloadWithCustomVariables( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["variables"].addChild( Gaffer.NameValuePlug( "test", IECore.IntData( 10 ), flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic ) )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s["variables"][0]["value"].setValue( 100 )
  		s.load()
  
  		self.assertEqual( len( s["variables"] ), 1 )
  		self.assertEqual( s["variables"][0]["value"].getValue(), 10 )
  
  	def testLoadCustomVariablesWithDefaultValues( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "test", IECore.IntData( 10 ), flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context().get( "test" ), 10 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( s2["variables"][p.getName()]["value"].getValue(), 10 )
  		self.assertEqual( s2.context().get( "test" ), 10 )
  
  	def testCurrentActionStage( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = GafferTest.AddNode()
  
  		actionStages = []
  		def f( plug ) :
  
  			actionStages.append( s.currentActionStage() )
  
  			if s.currentActionStage() != Gaffer.Action.Stage.Invalid :
  				self.assertFalse( s.undoAvailable() )
  				self.assertFalse( s.redoAvailable() )
  
  		c = s["n"].plugSetSignal().connect( f )
  
  		self.assertEqual( s.currentActionStage(), Gaffer.Action.Stage.Invalid )
  		self.assertEqual( len( actionStages ), 0 )
  
  		s["n"]["op1"].setValue( 10 )
  
  		self.assertEqual( len( actionStages ), 1 )
  		self.assertEqual( actionStages[-1], Gaffer.Action.Stage.Invalid )
  
  		with Gaffer.UndoScope( s ) :
  			s["n"]["op1"].setValue( 11 )
  
  		self.assertEqual( len( actionStages ), 2 )
  		self.assertEqual( actionStages[-1], Gaffer.Action.Stage.Do )
  
  		s.undo()
  
  		self.assertEqual( len( actionStages ), 3 )
  		self.assertEqual( actionStages[-1], Gaffer.Action.Stage.Undo )
  
  		s.redo()
  
  		self.assertEqual( len( actionStages ), 4 )
  		self.assertEqual( actionStages[-1], Gaffer.Action.Stage.Redo )
  
  		s.undo()
  
  		self.assertEqual( len( actionStages ), 5 )
  		self.assertEqual( actionStages[-1], Gaffer.Action.Stage.Undo )
  
  		self.assertEqual( s.currentActionStage(), Gaffer.Action.Stage.Invalid )
  
  	def testUndoListDoesntCreateReferenceCycles( self ) :
  
  		s = Gaffer.ScriptNode()
  		c = s.refCount()
  
  		s["n"] = Gaffer.Node()
  		s["n"]["p"] = Gaffer.IntPlug()
  
  		with Gaffer.UndoScope( s ) :
  			s.setName( "somethingElse" )
  			self.assertEqual( s.getName(), "somethingElse" )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s["n"].setName( "n2" )
  			self.assertEqual( s["n2"].getName(), "n2" )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			Gaffer.Metadata.registerValue( s, "test", 10 )
  			Gaffer.Metadata.registerValue( s["n2"], "test", 10 )
  			Gaffer.Metadata.registerValue( s["n2"]["p"], "test", 10 )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s["n3"] = Gaffer.Node()
  			n4 = Gaffer.Node( "n4" )
  			s.addChild( n4 )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s["n3"].addChild( s["n2"]["p"] )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s.addChild( s["n3"]["p"] )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s["n3"].addChild( s["p"] )
  		self.assertEqual( s.refCount(), c )
  
  		with Gaffer.UndoScope( s ) :
  			s.removeChild( s["n2"] )
  		self.assertEqual( s.refCount(), c )
  
  	def testErrorTolerantExecution( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["n"] = GafferTest.AddNode()
  
  		with IECore.CapturingMessageHandler() as c :
  			s.execute( 'parent["n"]["op1"].setValue( 101 )\niWillFail(); parent["n"]["op2"].setValue( 102 )', continueOnError=True )
  
  		self.assertEqual( s["n"]["op1"].getValue(), 101 )
  		self.assertEqual( s["n"]["op2"].getValue(), 102 )
  
  		self.assertEqual( len( c.messages ), 1 )
  		self.assertEqual( c.messages[0].level, IECore.Msg.Level.Error )
  		self.assertTrue( "Line 2" in c.messages[0].context )
  		self.assertTrue( "name 'iWillFail' is not defined" in c.messages[0].message )
  
  	def testExecuteReturnValue( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		self.assertEqual( s.execute( "a = 10" ), False )
  		self.assertEqual( s.execute( "a = 10", continueOnError=True ), False )
  
  		with IECore.CapturingMessageHandler() : # suppress error reporting, to avoid confusing test output
  			self.assertEqual( s.execute( "a = iDontExist", continueOnError=True ), True )
  
  	def testExecuteExceptionsIncludeLineNumber( self ) :
  
  		s = Gaffer.ScriptNode()
  		six.assertRaisesRegex( self, RuntimeError, "Line 2 .* name 'iDontExist' is not defined", s.execute, "a = 10\na=iDontExist" )
  
  	def testFileVersioning( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:milestoneVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:majorVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:minorVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:patchVersion" ), None )
  
  		s.serialiseToFile( self.temporaryDirectory() + "/test.gfr" )
  
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:milestoneVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:majorVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:minorVersion" ), None )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:patchVersion" ), None )
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:milestoneVersion" ), Gaffer.About.milestoneVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:majorVersion" ), Gaffer.About.majorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:minorVersion" ), Gaffer.About.minorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:patchVersion" ), Gaffer.About.patchVersion() )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2.load()
  
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:milestoneVersion" ), Gaffer.About.milestoneVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:majorVersion" ), Gaffer.About.majorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:minorVersion" ), Gaffer.About.minorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:patchVersion" ), Gaffer.About.patchVersion() )
  
  	def testFileVersioningUpdatesOnSave( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( os.path.dirname( __file__ ) + "/scripts/previousSerialisationVersion.gfr" )
  		s.load()
  
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:milestoneVersion" ), 0 )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:majorVersion" ), 14 )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:minorVersion" ), 0 )
  		self.assertEqual( Gaffer.Metadata.value( s, "serialiser:patchVersion" ), 0 )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s.save()
  
  		s2 = Gaffer.ScriptNode()
  		s2["fileName"].setValue( self.temporaryDirectory() + "/test.gfr" )
  		s2.load()
  
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:milestoneVersion" ), Gaffer.About.milestoneVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:majorVersion" ), Gaffer.About.majorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:minorVersion" ), Gaffer.About.minorVersion() )
  		self.assertEqual( Gaffer.Metadata.value( s2, "serialiser:patchVersion" ), Gaffer.About.patchVersion() )
  
  	def testFramesPerSecond( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertEqual( s["framesPerSecond"].getValue(), 24.0 )
  		self.assertEqual( s.context().getFramesPerSecond(), 24.0 )
  
  		s["framesPerSecond"].setValue( 48.0 )
  		self.assertEqual( s.context().getFramesPerSecond(), 48.0 )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise() )
  		self.assertEqual( s2["framesPerSecond"].getValue(), 48.0 )
  		self.assertEqual( s2.context().getFramesPerSecond(), 48.0 )
  
  	def testFrame( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertEqual( s["frame"].getValue(), 1 )
  		self.assertEqual( s.context().getFrame(), 1.0 )
  
  		s["frame"].setValue( 2.0 )
  		self.assertEqual( s.context().getFrame(), 2.0 )
  
  		s.context().setFrame( 4.0 )
  		self.assertEqual( s["frame"].getValue(), 4.0 )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise() )
  		self.assertEqual( s2["frame"].getValue(), 4.0 )
  		self.assertEqual( s2.context().getFrame(), 4.0 )
  
  	def testFrameRange( self ) :
  
  		s = Gaffer.ScriptNode()
  		self.assertEqual( s["frameRange"]["start"].getValue(), 1 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 100 )
  		self.assertEqual( s.context().get( "frameRange:start" ), 1 )
  		self.assertEqual( s.context().get( "frameRange:end" ), 100 )
  
  		s["frameRange"]["start"].setValue( 20 )
  		s["frameRange"]["end"].setValue( 50 )
  		self.assertEqual( s.context().get( "frameRange:start" ), 20 )
  		self.assertEqual( s.context().get( "frameRange:end" ), 50 )
  
  		# frame range remains valid
  		s["frameRange"]["end"].setValue( 15 )
  		self.assertEqual( s["frameRange"]["start"].getValue(), 15 )
  		self.assertEqual( s["frameRange"]["end"].getValue(), 15 )
  		self.assertEqual( s.context().get( "frameRange:start" ), 15 )
  		self.assertEqual( s.context().get( "frameRange:end" ), 15 )
  
  		s["frameRange"]["end"].setValue( 150 )
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise() )
  		self.assertEqual( s2["frameRange"]["start"].getValue(), 15 )
  		self.assertEqual( s2["frameRange"]["end"].getValue(), 150 )
  		self.assertEqual( s2.context().get( "frameRange:start" ), 15 )
  		self.assertEqual( s2.context().get( "frameRange:end" ), 150 )
  
  	def testLineNumberForExecutionSyntaxError( self ) :
  
  		s = Gaffer.ScriptNode()
  		six.assertRaisesRegex( self,
  			IECore.Exception,
  			"^Line 2",
  			s.execute,
  			inspect.cleandoc(
  				"""
  				a = 10
  				i am a syntax error
  				b = 20
  				"""
  			)
  		)
  
  	def testFileNameInExecutionError( self ) :
  
  		fileName = self.temporaryDirectory() + "/test.gfr"
  		with open( fileName, "w" ) as f :
  			f.write( "a = 10\n" )
  			f.write( "a = iDontExist\n" )
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( fileName )
  
  		for method in ( s.load, functools.partial( s.executeFile, fileName ) ) :
  
  			six.assertRaisesRegex( self,
  				RuntimeError,
  				"Line 2 of " + fileName + " : NameError: name 'iDontExist' is not defined",
  				method
  			)
  
  			with IECore.CapturingMessageHandler() as mh :
  				method( continueOnError = True )
  
  			self.assertEqual( len( mh.messages ), 1 )
  			self.assertEqual( mh.messages[0].context, "Line 2 of " + fileName )
  			self.assertTrue( "NameError: name 'iDontExist' is not defined" in mh.messages[0].message )
  
  	def testIsExecuting( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		self.assertFalse( s.isExecuting() )
  
  		self.__wasExecuting = []
  		def f( script, child ) :
  			self.__wasExecuting.append( script.isExecuting() )
  
  		c = s.childAddedSignal().connect( f )
  
  		s["n"] = GafferTest.AddNode()
  
  		# add a reference so we guarantee it works with nested loads
  		s["n1"] = GafferTest.AddNode()
  		s["n2"] = GafferTest.AddNode()
  		s["n2"]["op1"].setInput( s["n1"]["sum"] )
  		b = Gaffer.Box.create( s, Gaffer.StandardSet( [ s["n1"] ] ) )
  		Gaffer.PlugAlgo.promote( b["n1"]["op1"] )
  
  		b.exportForReference( self.temporaryDirectory() + "/test.grf" )
  
  		s["r"] = Gaffer.Reference()
  		s["r"].load( self.temporaryDirectory() + "/test.grf" )
  
  		s["r"]["op1"].setInput( s["n"]["sum"] )
  
  		s["x"] = GafferTest.AddNode()
  		self.assertFalse( any( self.__wasExecuting ) )
  
  		self.__wasExecuting = []
  
  		# connecting n to r and then to x guarantees the order of serialisation
  		s["x"]["op1"].setInput( s["r"]["sum"] )
  
  		ss = s.serialise( filter = Gaffer.StandardSet( [ s["n"], s["r"], s["x"] ] ) )
  		s.execute( ss )
  		self.assertTrue( all( self.__wasExecuting ) )
  
  		self.__wasExecuting = []
  		self.assertRaises( RuntimeError, s.execute, ss + "\nsyntaxError" )
  		self.assertFalse( s.isExecuting() )
  
  	def testReconnectionOfChildPlug( self ) :
  
  		class NestedPlugsNode( Gaffer.DependencyNode ) :
  
  			def __init__( self, name = "NestedOutputNode" ) :
  
  				Gaffer.DependencyNode.__init__( self, name )
  
  				self["in"] = Gaffer.Plug()
  				self["in"]["a"] = Gaffer.IntPlug()
  				self["in"]["b"] = Gaffer.IntPlug()
  
  				self["out"] = Gaffer.Plug( direction = Gaffer.Plug.Direction.Out )
  				self["out"]["a"] = Gaffer.IntPlug( direction = Gaffer.Plug.Direction.Out )
  				self["out"]["b"] = Gaffer.IntPlug( direction = Gaffer.Plug.Direction.Out )
  
  			def correspondingInput( self, output ) :
  
  				if output.isSame( self["out"] ) :
  					return self["in"]
  
  				if output.isSame( self["out"]["a"] ) :
  					return self["in"]["a"]
  
  				if output.isSame( self["out"]["b"] ) :
  					return self["in"]["b"]
  
  				return Gaffer.DependencyNode.correspondingInput( self, output )
  
  		s = Gaffer.ScriptNode()
  
  		s["n1"] = NestedPlugsNode()
  		s["n2"] = NestedPlugsNode()
  		s["n3"] = NestedPlugsNode()
  
  		# check top level connection
  		s["n2"]["in"].setInput( s["n1"]["out"] )
  		s["n3"]["in"].setInput( s["n2"]["out"] )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ s["n2"] ] ) )
  		self.assertTrue( s["n3"]["in"].getInput().isSame( s["n1"]["out"] ) )
  
  		# check connection for nested plug
  		s["n4"] = NestedPlugsNode()
  		s["n3"]["in"].setInput( None )
  		s["n3"]["in"]["a"].setInput( s["n1"]["out"]["a"] )
  		s["n4"]["in"]["a"].setInput( s["n3"]["out"]["a"] )
  
  		s.deleteNodes( filter = Gaffer.StandardSet( [ s["n3"] ] ) )
  		self.assertTrue( s["n4"]["in"]["a"].getInput().isSame( s["n1"]["out"]["a"] ) )
  
  	def testPasteWithContinueOnError( self ) :
  
  		app = Gaffer.ApplicationRoot()
  		script = Gaffer.ScriptNode()
  
  		app["scripts"]["s"] = script
  
  		app.setClipboardContents( IECore.StringData(
  			inspect.cleandoc(
  				"""
  				iAmAnError
  				parent.addChild( Gaffer.Node() )
  				"""
  			)
  		) )
  
  		six.assertRaisesRegex( self, RuntimeError, "iAmAnError", script.paste )
  		self.assertEqual( len( script.children( Gaffer.Node ) ), 0 )
  
  		with IECore.CapturingMessageHandler() as mh :
  			script.paste( continueOnError = True )
  
  		self.assertEqual( len( mh.messages ), 1 )
  		self.assertEqual( mh.messages[0].level, IECore.Msg.Level.Error )
  		self.assertTrue( "iAmAnError" in mh.messages[0].message )
  		self.assertEqual( len( script.children( Gaffer.Node ) ), 1 )
  
  	def testErrorTolerantExecutionWithSyntaxError( self ) :
  
  		script = Gaffer.ScriptNode()
  
  		with IECore.CapturingMessageHandler() as mh :
  			script.execute( "import", continueOnError = True )
  
  		self.assertEqual( len( mh.messages ), 1 )
  		self.assertIn( "SyntaxError: invalid syntax", mh.messages[0].message )
  
  	def testImport( self ) :
  
  		s1 = Gaffer.ScriptNode()
  
  		s1["n1"] = GafferTest.AddNode()
  		s1["n2"] = GafferTest.AddNode()
  		s1["n2"]["op1"].setInput( s1["n1"]["sum"] )
  
  		s1["p"] = Gaffer.Plug()
  		s1["frameRange"]["start"].setValue( -10 )
  		s1["frameRange"]["end"].setValue( 101 )
  		s1["variables"].addChild( Gaffer.NameValuePlug( "test", "test" ) )
  
  		fileName = self.temporaryDirectory() + "/toImport.gfr"
  		s1.serialiseToFile( fileName )
  
  		s2 = Gaffer.ScriptNode()
  		s2.importFile( fileName )
  
  		self.assertIn( "n1", s2 )
  		self.assertIn( "n2", s2 )
  		self.assertTrue( s2["n2"]["op1"].getInput().isSame( s2["n1"]["sum"] ) )
  
  		self.assertNotIn( "p", s2 )
  		self.assertEqual( len( s2["variables"] ), 0 )
  
  	def testReadOnlyMetadata( self ) :
  
  		fileName = self.temporaryDirectory() + "/test.gfr"
  
  		s = Gaffer.ScriptNode()
  		self.assertFalse( Gaffer.MetadataAlgo.getReadOnly( s ) )
  
  		s["fileName"].setValue( fileName )
  		self.assertFalse( Gaffer.MetadataAlgo.getReadOnly( s ) )
  		s.save()
  		self.assertFalse( Gaffer.MetadataAlgo.getReadOnly( s ) )
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( fileName )
  		s.load()
  		self.assertFalse( Gaffer.MetadataAlgo.getReadOnly( s ) )
  
  		os.chmod( s["fileName"].getValue(), stat.S_IREAD | stat.S_IRGRP | stat.S_IROTH )
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( fileName )
  		s.load()
  		self.assertTrue( Gaffer.MetadataAlgo.getReadOnly( s ) )
  
  		s["fileName"].setValue( self.temporaryDirectory() + "/test2.gfr" )
  		self.assertFalse( Gaffer.MetadataAlgo.getReadOnly( s ) )
  
  	def testDisableContextVariable( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "test", 10, defaultEnabled = True, name = "test", flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context()["test"], 10 )
  
  		p["enabled"].setValue( False )
  		self.assertNotIn( "test", s.context() )
  
  		s2 = Gaffer.ScriptNode()
  		s2.execute( s.serialise() )
  		self.assertNotIn( "test", s2.context() )
  		s2["variables"]["test"]["enabled"].setValue( True )
  		self.assertEqual( s2.context()["test"], 10 )
  
  	def testDeleteContextVariable( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "test", 10, defaultEnabled = True, name = "test", flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context()["test"], 10 )
  
  		s["variables"].removeChild( p )
  		self.assertNotIn( "test", s.context() )
  
  	def testCompoundNumericContextVariable( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "test", imath.V3i( 1, 2, 3 ), flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context()["test"], imath.V3i( 1, 2, 3 ) )
  
  		p["value"]["y"].setValue( 10 )
  		self.assertEqual( s.context()["test"], imath.V3i( 1, 10, 3 ) )
  
  	def testDuplicateContextVariables( self ) :
  
  		# We don't want people to specify the same context variable twice,
  		# but if they do, we want to implement a simple rule : last enabled
  		# one in the list wins. This is the same rule used for CompoundDataPlugs
  		# everywhere.
  
  		s = Gaffer.ScriptNode()
  
  		p1 = Gaffer.NameValuePlug( "test", 1, defaultEnabled = True, flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		p2 = Gaffer.NameValuePlug( "test", 2, defaultEnabled = True, flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p1 )
  		s["variables"].addChild( p2 )
  		self.assertEqual( s.context()["test"], 2 )
  
  		p1["value"].setValue( 10 )
  		self.assertEqual( s.context()["test"], 2 )
  
  		p2["enabled"].setValue( False )
  		self.assertEqual( s.context()["test"], 10 )
  
  		p2["enabled"].setValue( True )
  		self.assertEqual( s.context()["test"], 2 )
  
  		s["variables"].removeChild( p2 )
  		self.assertEqual( s.context()["test"], 10 )
  
  		s["variables"].removeChild( p1 )
  		self.assertNotIn( "test", s.context() )
  
  	def testExternalContextVariable( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		# We don't really want people to manipulate the context directly like
  		# this; we want them to use `ScriptNode::variablesPlug()` instead. But
  		# it seems plausible that people would do this to implement a sort of
  		# non-persistent "context pinning" for interactive use. Until we support
  		# such a feature natively, make sure that we don't remove variables we
  		# know nothing about.
  		s.context()["externalTest"] = 10
  
  		p = Gaffer.NameValuePlug( "test", 1, defaultEnabled = True, flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertEqual( s.context()["externalTest"], 10 )
  		self.assertEqual( s.context()["test"], 1 )
  
  		p["enabled"].setValue( False )
  		self.assertEqual( s.context()["externalTest"], 10 )
  		self.assertNotIn( "test", s.context() )
  
  		p["enabled"].setValue( True )
  		self.assertEqual( s.context()["externalTest"], 10 )
  		self.assertEqual( s.context()["test"], 1 )
  
  		s["variables"].removeChild( p )
  		self.assertEqual( s.context()["externalTest"], 10 )
  		self.assertNotIn( "test", s.context() )
  
  	def testChangeContextVariableName( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		p = Gaffer.NameValuePlug( "", 1, defaultEnabled = True, flags = Gaffer.Plug.Flags.Default | Gaffer.Plug.Flags.Dynamic )
  		s["variables"].addChild( p )
  		self.assertNotIn( "", s.context() )
  
  		p["name"].setValue( "test" )
  		self.assertEqual( s.context()["test"], 1 )
  
  		p["name"].setValue( "testTwo" )
  		self.assertEqual( s.context()["testTwo"], 1 )
  		self.assertNotIn( "test", s.context() )
  
  		p["name"].setValue( "" )
  		self.assertNotIn( "testTwo", s.context() )
  
  	def testCancellationDuringLoad( self ) :
  
  		s = Gaffer.ScriptNode()
  		s["fileName"].setValue( os.path.join( os.path.dirname( __file__ ), "scripts", "previousSerialisationVersion.gfr" ) )
  
  		context = Gaffer.Context()
  		canceller = IECore.Canceller()
  		with Gaffer.Context( context, canceller ) :
  			canceller.cancel()
  			with self.assertRaises( IECore.Cancelled ) :
  				s.load()
  
  	def testCancellationDuringExecute( self ) :
  
  		s = Gaffer.ScriptNode()
  
  		context = Gaffer.Context()
  		canceller = IECore.Canceller()
  		with Gaffer.Context( context, canceller ) :
  			canceller.cancel()
  			# Execution is done all in one go, and there's no point cancelling
  			# at the end when we've done all of the work anyway.
  			s.execute( "script.addChild( Gaffer.Node() )", continueOnError = False )
  			with self.assertRaises( IECore.Cancelled ) :
  				# Execution is done line-by-line, so making regular cancellation
  				# checks makes sense.
  				s.execute( "script.addChild( Gaffer.Node() )", continueOnError = True )
  
  	def testCancellationDuringSerialise( self ) :
  
  		s = Gaffer.ScriptNode()
  		context = Gaffer.Context()
  		canceller = IECore.Canceller()
  		with Gaffer.Context( context, canceller ) :
  			canceller.cancel()
  			with self.assertRaises( IECore.Cancelled ) :
  				s.serialise()
  
  if __name__ == "__main__":
  	unittest.main()
  