SF bug #785222: zlib monotonic test

rhettinger · rhettinger · commit 6d362b25c512 · 2003-08-31T04:35:24.000Z
For smaller datasets, it is not always true the increasing the compression
level always results in better compression.  Removed the test which made
this invalid assumption.
diff --git a/Lib/test/test_zlib.py b/Lib/test/test_zlib.py
@@ -96,17 +96,6 @@ def test_speech128(self):
         x = zlib.compress(data)
         self.assertEqual(zlib.decompress(x), data)
 
-    def test_monotonic(self):
-        # higher compression levels should not expand compressed size
-        data = hamlet_scene * 8 * 16
-        last = length = len(zlib.compress(data, 0))
-        self.failUnless(last > len(data), "compress level 0 always expands")
-        for level in range(10):
-            length = len(zlib.compress(data, level))
-            self.failUnless(length <= last,
-                            'compress level %d more effective than %d!' % (
-                                            level-1, level))
-            last = length
 
 
 
