avoid .split() in for loops and use tuples instead

avoid .split() in for loops and use tuples instead

split can be more readable for longer lists like the list in
dirstate.invalidate. As dirstate.invalidate is used in wlock() and therefoe
used heavily, I think it's worth avoiding a split there too.

--- a/mercurial/dirstate.py	Mon Dec 06 16:56:06 2010 +0100
+++ b/mercurial/dirstate.py	Thu Dec 02 03:43:06 2010 +0100
@@ -230,7 +230,8 @@
             self._pl = p
 
     def invalidate(self):
-        for a in "_map _copymap _foldmap _branch _pl _dirs _ignore".split():
+        for a in ("_map", "_copymap", "_foldmap", "_branch", "_pl", "_dirs",
+                "_ignore"):
             if a in self.__dict__:
                 delattr(self, a)
         self._dirty = False

--- a/mercurial/localrepo.py	Mon Dec 06 16:56:06 2010 +0100
+++ b/mercurial/localrepo.py	Thu Dec 02 03:43:06 2010 +0100
@@ -733,7 +733,7 @@
         self._branchcachetip = None
 
     def invalidate(self):
-        for a in "changelog manifest".split():
+        for a in ("changelog", "manifest"):
             if a in self.__dict__:
                 delattr(self, a)
         self.invalidatecaches()

--- a/mercurial/util.py	Mon Dec 06 16:56:06 2010 +0100
+++ b/mercurial/util.py	Thu Dec 02 03:43:06 2010 +0100
@@ -1099,7 +1099,7 @@
         if not defaults:
             defaults = {}
         now = makedate()
-        for part in "d mb yY HI M S".split():
+        for part in ("d", "mb", "yY", "HI", "M", "S"):
             if part not in defaults:
                 if part[0] in "HMS":
                     defaults[part] = "00"
@@ -1146,7 +1146,7 @@
 
     def upper(date):
         d = dict(mb="12", HI="23", M="59", S="59")
-        for days in "31 30 29".split():
+        for days in ("31", "30", "29"):
             try:
                 d["d"] = days
                 return parsedate(date, extendeddateformats, d)[0]