other micro optimisations

Author: tomato42

tlslite/utils/codec.py

@@ -318,11 +318,12 @@ def getFixBytes(self, lengthBytes):
 
         :rtype: bytearray
         """
-        if self.index + lengthBytes > len(self.bytes):
+        end = self.index + lengthBytes
+        if end > len(self.bytes):
             raise DecodeError("Read past end of buffer")
-        bytes = self.bytes[self.index : self.index+lengthBytes]
+        ret = self.bytes[self.index : end]
         self.index += lengthBytes
-        return bytes
+        return ret
 
     def skip_bytes(self, length):
         """Move the internal pointer ahead length bytes."""

tlslite/utils/rsakey.py

@@ -534,11 +534,10 @@ def _addPKCS1Padding(self, bytes, blockType):
             pad = bytearray(0)
             while len(pad) < padLength:
                 padBytes = getRandomBytes(padLength * 2)
-                pad = [b for b in padBytes if b != 0]
+                pad = [b for b in padBytes if b]
                 pad = pad[:padLength]
         else:
             raise AssertionError()
 
         padding = bytearray([0,blockType] + pad + [0])
-        paddedBytes = padding + bytes
-        return paddedBytes
+        return padding + bytes