ColorChooser : Don't emit signals with inconsistent internal state

Changes.md

@@ -18,6 +18,7 @@ Fixes
 - Cycles : Fixed rendering to the Catalogue using the batch Render node (#5905). Note that rendering a mixture of Catalogue and file outputs is still not supported, and in this case any file outputs will be ignored.
 - CodeWidget : Fixed bug that could prevent changes from being committed while the completion menu was visible.
 - Loop : Fixed handling of empty `indexVariable`. This now disables the Loop instead of creating an unnamed context variable.
+- ColorChooser : Fixed emission of `colorChangedSignal()` while the widget was in an inconsistent internal state.
 
 API
 ---

python/GafferUI/ColorChooser.py

@@ -257,15 +257,12 @@ def __setColorInternal( self, color, reason, hsv = False ) :
 			GafferUI.NumericWidget.ValueChangedReason.DragEnd,
 		)
 
-		previousColor = self.__colorHSV if hsv else self.__color
+		colorChanged = color != ( self.__colorHSV if hsv else self.__color )
 
-		if color != previousColor or dragBeginOrEnd :
-			# we never optimise away drag begin or end, because it's important
-			# that they emit in pairs.
+		if colorChanged :
 			colorRGB = color.hsv2rgb() if hsv else color
 			self.__color = colorRGB
 			self.__colorSwatch.setColor( colorRGB )
-			self.__colorChangedSignal( self, reason )
 
 			hsv = color if hsv else color.rgb2hsv()
 
@@ -281,6 +278,11 @@ def __setColorInternal( self, color, reason, hsv = False ) :
 		# in NumericWidget.
 		self.__updateUIFromColor()
 
+		if colorChanged or dragBeginOrEnd :
+			# We never optimise away drag begin or end, because it's important
+			# that they emit in pairs.
+			self.__colorChangedSignal( self, reason )
+
 	def __updateUIFromColor( self ) :
 
 		with Gaffer.Signals.BlockedConnection( self.__componentValueChangedConnections ) :