Add a check to prevent we make path data longer by "optimization"

scour/scour.py

@@ -2286,6 +2286,10 @@ def cleanPath(element, options) :
    path = newPath
 
    newPathStr = serializePath(path, options)
+
+   # if for whatever reason we actually made the path longer don't use it
+   # TODO: maybe we could compare path lengths after each optimization step and use the shortest
+   if len(newPathStr) <= len(oldPathStr):
       numBytesSavedInPathData += ( len(oldPathStr) - len(newPathStr) )
       element.setAttribute('d', newPathStr)
 

testscour.py

@@ -685,6 +685,14 @@ class ChangeQuadToShorthandInPath(unittest.TestCase):
 		self.assertEqual(path.getAttribute('d'), 'm10 100q50-50 100 0t100 0',
 			'Did not change quadratic curves into shorthand curve segments in path')
 
+class DoNotOptimzePathIfLarger(unittest.TestCase):
+	def runTest(self):
+		p = scour.scourXmlFile('unittests/path-no-optimize.svg').getElementsByTagNameNS(SVGNS, 'path')[0];
+		self.assertTrue(len(p.getAttribute('d')) <= len("M100,100 L200.12345,200.12345 C215,205 185,195 200.12,200.12 Z"),
+			'Made path data longer during optimization')
+        # this was the scoured path data as of 2016-08-31 without the length check in cleanPath(): 
+        #    d="m100 100l100.12 100.12c14.877 4.8766-15.123-5.1234-0.00345-0.00345z"
+
 class HandleEncodingUTF8(unittest.TestCase):
 	def runTest(self):
 		doc = scour.scourXmlFile('unittests/encoding-utf8.svg')

unittests/path-no-optimize.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="210" height="210">
+  <path stroke="yellow" fill="red" d="M100,100 L200.12345,200.12345 C215,205 185,195 200.12,200.12 Z"/>
+</svg>