--- a/mercurial/context.py
+++ b/mercurial/context.py
@@ -203,7 +203,7 @@ class filectx(object):
     def data(self): return self._filelog.read(self._filenode)
     def renamed(self): return self._filelog.renamed(self._filenode)
     def path(self): return self._path
-    def size(self): return self._filelog.len(self._filerev)
+    def size(self): return self._filelog.size(self._filerev)
 
     def cmp(self, text): return self._filelog.cmp(self._filenode, text)
 

--- a/mercurial/filelog.py
+++ b/mercurial/filelog.py
@@ -65,15 +65,15 @@ class filelog(revlog):
             return (m["copy"], bin(m["copyrev"]))
         return False
 
-    def len(self, rev):
-        """return the len of a given revision"""
+    def size(self, rev):
+        """return the size of a given revision"""
 
         # for revisions with renames, we have to go the slow way
         node = self.node(rev)
         if self.renamed(node):
             return len(self.read(node))
 
-        return self.size(rev)
+        return revlog.size(self, rev)
 
     def cmp(self, node, text):
         """compare text with a given file revision"""

--- a/mercurial/hgweb/hgweb_mod.py
+++ b/mercurial/hgweb/hgweb_mod.py
@@ -441,13 +441,13 @@ class hgweb(object):
 
         files = {}
 
-        p = path[1:]
-        if p and p[-1] != "/":
-            p += "/"
-        l = len(p)
+        if path and path[-1] != "/":
+            path += "/"
+        l = len(path)
+        abspath = "/" + path
 
         for f,n in mf.items():
-            if f[:l] != p:
+            if f[:l] != path:
                 continue
             remain = f[l:]
             if "/" in remain:
@@ -483,15 +483,15 @@ class hgweb(object):
                     continue
 
                 yield {"parity": self.stripes(parity),
-                       "path": os.path.join(path, f),
+                       "path": os.path.join(abspath, f),
                        "basename": f[:-1]}
                 parity += 1
 
         yield self.t("manifest",
                      rev=ctx.rev(),
                      node=hex(node),
-                     path=path,
-                     up=_up(path),
+                     path=abspath,
+                     up=_up(abspath),
                      fentries=filelist,
                      dentries=dirlist,
                      archives=self.archivelist(hex(node)))
@@ -639,6 +639,7 @@ class hgweb(object):
     # find tag, changeset, file
 
     def cleanpath(self, path):
+        path = path.lstrip('/')
         return util.canonpath(self.repo.root, '', path)
 
     def run(self):
@@ -865,16 +866,15 @@ class hgweb(object):
         self.do_changeset(req)
 
     def do_file(self, req):
-        path = req.form.get('file', [''])[0]
+        path = self.cleanpath(req.form.get('file', [''])[0])
         if path:
             try:
                 req.write(self.filerevision(self.filectx(req)))
                 return
             except hg.RepoError:
                 pass
-            path = self.cleanpath(path)
 
-        req.write(self.manifest(self.changectx(req), '/' + path))
+        req.write(self.manifest(self.changectx(req), path))
 
     def do_diff(self, req):
         self.do_filediff(req)

--- a/mercurial/merge.py
+++ b/mercurial/merge.py
@@ -384,13 +384,9 @@ def update(repo, node, branchmerge, forc
         if branchmerge:
             raise util.Abort(_("there is nothing to merge, just use "
                                "'hg update' or look at 'hg heads'"))
-    elif not branchmerge:
-        if not overwrite:
-            if wc.files():
-                raise util.Abort(_("outstanding uncommited changes, use "
-                                   "'hg update -C' to lose changes"))
-            else:
-                overwrite = True
+    elif not (overwrite or branchmerge):
+        raise util.Abort(_("update spans branches, use 'hg merge' "
+                           "or 'hg update -C' to lose changes"))
     if branchmerge and not forcemerge:
         if wc.files():
             raise util.Abort(_("outstanding uncommitted changes"))

--- a/tests/test-merge5
+++ b/tests/test-merge5
@@ -12,13 +12,9 @@ hg commit -m"comment #1" -d "1000000 0"
 hg update 0
 rm b
 hg commit -A -m"comment #2" -d "1000000 0"
-
-echo This is file a > a
 # in theory, we shouldn't need the "-y" below, but it prevents
 # this test from hanging when "hg update" erroneously prompts the
 # user for "keep or delete"
-hg update -y 1 # should fail (unclean repo)
-hg revert a
 hg update -y 1
 
 exit 0

--- a/tests/test-merge5.out
+++ b/tests/test-merge5.out
@@ -1,4 +1,3 @@
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 removing b
-abort: outstanding uncommited changes, use 'hg update -C' to lose changes
-1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+abort: update spans branches, use 'hg merge' or 'hg update -C' to lose changes

--- a/tests/test-up-local-change.out
+++ b/tests/test-up-local-change.out
@@ -93,7 +93,7 @@ user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     2
 
-abort: outstanding uncommited changes, use 'hg update -C' to lose changes
+abort: update spans branches, use 'hg merge' or 'hg update -C' to lose changes
 failed
 abort: outstanding uncommitted changes
 failed