Remove duplicate gradient stops and update unit tests

scour.py

@@ -29,7 +29,6 @@
 #
 # * Specify a limit to the precision of all positional elements.
 # * Clean up Definitions
-#  * Remove duplicate gradient stops
 #  * Collapse duplicate gradient definitions
 #  * Remove gradients that are only referenced by one other gradient
 # * Clean up CSS
@@ -47,11 +46,11 @@
 
 # Next Up:
 # + Remove unnecessary nested <g> elements
-# - Remove duplicate gradient stops (same offset, stop-color, stop-opacity)
+# + Remove duplicate gradient stops (same offset, stop-color, stop-opacity)
 # - Convert all colors to #RRGGBB format
 # - Reduce #RRGGBB format to #RGB format when possible
 # - rework command-line argument processing so that options are configurable
-# - remove unreferenced patterns? https://bugs.edge.launchpad.net/ubuntu/+source/human-icon-theme/+bug/361667/
+https://bugs.edge.launchpad.net/ubuntu/+source/human-icon-theme/+bug/361667/
 
 # Some notes to not forget:
 # - removing unreferenced IDs loses some semantic information
@@ -309,8 +308,33 @@ def removeNestedGroups(node):
 	# now recurse for children
 	for child in node.childNodes:
 		if child.nodeType == 1:
-			num += removeNestedGroups(child)
-		
+			num += removeNestedGroups(child)		
+	return num
+
+def removeDuplicateGradientStops(doc):
+	global numElemsRemoved
+	num = 0
+	
+	for gradType in ['linearGradient', 'radialGradient']:
+		for grad in doc.getElementsByTagNameNS(NS['SVG'], gradType):
+			stops = {}
+			stopsToRemove = []
+			for stop in grad.getElementsByTagNameNS(NS['SVG'], 'stop'):
+				offset = string.atof(stop.getAttribute('offset'))
+				color = stop.getAttribute('stop-color')
+				opacity = stop.getAttribute('stop-opacity')
+				if stops.has_key(offset) :
+					oldStop = stops[offset]
+					if oldStop[0] == color and oldStop[1] == opacity:
+						stopsToRemove.append(stop)
+				stops[offset] = [color, opacity]
+				
+			for stop in stopsToRemove:
+				stop.parentNode.removeChild(stop)
+				num += 1
+				numElemsRemoved += 1
+	
+	# linear gradients
 	return num
 
 coord = re.compile("\\-?\\d+\\.?\\d*")
@@ -668,6 +692,9 @@ def scourString(in_string):
 	while removeNestedGroups(doc.documentElement) > 0:
 		pass
 
+	while removeDuplicateGradientStops(doc) > 0:
+		pass
+	
 	# clean path data
 	for elem in doc.documentElement.getElementsByTagNameNS(NS['SVG'], 'path') :
 		cleanPath(elem)

testscour.py

@@ -139,13 +139,21 @@ class RemoveUselessNestedGroups(unittest.TestCase):
 		self.assertEquals(len(doc.getElementsByTagNameNS(SVGNS, 'g')), 1,
 			'Useless nested groups not removed' )
 
-# These tests will fail at present
-class RemoveDuplicateGradientStops(unittest.TestCase):
+class RemoveDuplicateLinearGradientStops(unittest.TestCase):
 	def runTest(self):
 		doc = scour.scourXmlFile('unittests/duplicate-gradient-stops.svg')
-		self.assertEquals(len(doc.getElementsByTagNameNS(SVGNS, 'stop')), 3,
-			'Duplicate gradient stops not removed' )
+		grad = doc.getElementsByTagNameNS(SVGNS, 'linearGradient')
+		self.assertEquals(len(grad[0].getElementsByTagNameNS(SVGNS, 'stop')), 3,
+			'Duplicate linear gradient stops not removed' )
 
+class RemoveDuplicateRadialGradientStops(unittest.TestCase):
+	def runTest(self):
+		doc = scour.scourXmlFile('unittests/duplicate-gradient-stops.svg')
+		grad = doc.getElementsByTagNameNS(SVGNS, 'radialGradient')
+		self.assertEquals(len(grad[0].getElementsByTagNameNS(SVGNS, 'stop')), 3,
+			'Duplicate radial gradient stops not removed' )
+
+# These tests will fail at present
 #class NoInkscapeAttributes(unittest.TestCase):
 #	def runTest(self):
 #		self.assertNotEquals(walkTree(scour.scourXmlFile('unittests/inkscape.svg').documentElement,

unittests/duplicate-gradient-stops.svg

@@ -1,11 +1,18 @@
 <svg xmlns="http://www.w3.org/2000/svg">
   <defs>
-    <linearGradient id="grad" x1="0" y1="0" x2="0" y2="1">
+    <linearGradient id="lingrad" x1="0" y1="0" x2="0" y2="1">
       <stop offset="0" stop-color="red" />
       <stop offset="0.5" stop-color="blue" />
       <stop offset="0.5" stop-color="blue" />
       <stop offset="1.0" stop-color="green" />
     </linearGradient>
+    <radialGradient id="radgrad">
+      <stop offset="0" stop-color="red" />
+      <stop offset="0.5" stop-color="blue" />
+      <stop offset="0.5" stop-color="blue" />
+      <stop offset="1.0" stop-color="green" />
+    </radialGradient>
   </defs>
-  <rect width="300" height="300" fill="url(#grad)" />
+  <rect width="300" height="300" fill="url(#lingrad)" />
+  <rect width="300" height="300" fill="url(#radgrad)" />
 </svg>