Rev 338: Simplify fetch code, avoid extra roundtrip when possible. in http://people.samba.org/bzr/jelmer/bzr-svn/bzr.dev

[Jelmer Vernooij]

------------------------------------------------------------
revno: 338
revision-id: jelmer at samba.org-20061230192957-nyzdptkm4iu91jm0
parent: jelmer at samba.org-20061230174926-kprsbiva815mc835
committer: Jelmer Vernooij <jelmer at samba.org>
branch nick: main
timestamp: Sat 2006-12-30 20:29:57 +0100
message:
  Simplify fetch code, avoid extra roundtrip when possible.
modified:
  fetch.py                       fetch.py-20060625004942-x2lfaib8ra707a8p-1
=== modified file 'fetch.py'
--- a/fetch.py	2006-12-30 17:49:26 +0000
+++ b/fetch.py	2006-12-30 19:29:57 +0000
@@ -288,21 +288,15 @@
         # (or youngest_revnum) and call self.target.add_revision() 
         # or self.target.add_inventory() each time
         if revision_id is None:
-            path = None
-            until_revnum = self.source._latest_revnum
+            history_iterator = self.source.follow_history(self.source._latest_revnum)
         else:
             (path, until_revnum) = self.source.parse_revision_id(revision_id)
+            history_iterator = self.source.follow_branch(path, until_revnum)
 
-        repos_root = self.source.transport.get_repos_root()
-        
         needed = []
         parents = {}
         prev_revid = None
-        if path is None:
-            it = self.source.follow_history(until_revnum)
-        else:
-            it = self.source.follow_branch(path, until_revnum)
-        for (branch, revnum) in it:
+        for (branch, revnum) in history_iterator:
             revid = self.source.generate_revision_id(revnum, branch)
 
             if prev_revid is not None:
@@ -313,8 +307,14 @@
             if not self.target.has_revision(revid):
                 needed.append((branch, revnum, revid))
 
+        if len(needed) == 0:
+            # Nothing to fetch
+            return
+
         parents[prev_revid] = None
 
+        repos_root = self.source.transport.get_repos_root()
+
         needed.reverse()
         prev_revid = None
         transport = self.source.transport