# HG changeset patch
# User Alexander Plavin <me@aplavin.ru>
# Date 1374704559 -14400
#      Thu Jul 25 02:22:39 2013 +0400
# Branch stable
# Node ID 002b711a3e8af864b2a284b057320a777b4ee147
# Parent  02c71f96eb6c7af66131c9a17973b64d2dfa8a5b
hgweb: fix incorrect way to count revisions in log (issue3977)

Actual amount of revisions is used now instead of their numbers in the repo
before to deal with skipped numbers correctly.
This iterates starting from the newest revision (which is shown on top)
yielding up to the specified count, instead of the reversed order used before.
Effect of this change on efficiency is negligible, when the same changesets are
returned.

diff --git a/mercurial/hgweb/webcommands.py b/mercurial/hgweb/webcommands.py
--- a/mercurial/hgweb/webcommands.py
+++ b/mercurial/hgweb/webcommands.py
@@ -200,38 +200,37 @@
             return _search(web, req, tmpl) # XXX redirect to 404 page?
 
     def changelist(latestonly, **map):
-        l = [] # build a list in forward order for efficiency
         revs = []
-        if start < end:
-            revs = web.repo.changelog.revs(start, end - 1)
+        if pos != -1:
+            revs = web.repo.changelog.revs(pos, 0)
         if latestonly:
-            for r in revs:
-                pass
-            revs = (r,)
+            revs = (next(revs),)
+        curcount = 0
         for i in revs:
             ctx = web.repo[i]
             n = ctx.node()
             showtags = webutil.showtag(web.repo, tmpl, 'changelogtag', n)
             files = webutil.listfilediffs(tmpl, ctx.files(), n, web.maxfiles)
 
-            l.append({"parity": parity.next(),
-                      "author": ctx.user(),
-                      "parent": webutil.parents(ctx, i - 1),
-                      "child": webutil.children(ctx, i + 1),
-                      "changelogtag": showtags,
-                      "desc": ctx.description(),
-                      "extra": ctx.extra(),
-                      "date": ctx.date(),
-                      "files": files,
-                      "rev": i,
-                      "node": hex(n),
-                      "tags": webutil.nodetagsdict(web.repo, n),
-                      "bookmarks": webutil.nodebookmarksdict(web.repo, n),
-                      "inbranch": webutil.nodeinbranch(web.repo, ctx),
-                      "branches": webutil.nodebranchdict(web.repo, ctx)
-                     })
-        for e in reversed(l):
-            yield e
+            curcount += 1
+            if curcount > revcount:
+                break
+            yield {"parity": parity.next(),
+                   "author": ctx.user(),
+                   "parent": webutil.parents(ctx, i - 1),
+                   "child": webutil.children(ctx, i + 1),
+                   "changelogtag": showtags,
+                   "desc": ctx.description(),
+                   "extra": ctx.extra(),
+                   "date": ctx.date(),
+                   "files": files,
+                   "rev": i,
+                   "node": hex(n),
+                   "tags": webutil.nodetagsdict(web.repo, n),
+                   "bookmarks": webutil.nodebookmarksdict(web.repo, n),
+                   "inbranch": webutil.nodeinbranch(web.repo, ctx),
+                   "branches": webutil.nodebranchdict(web.repo, ctx)
+            }
 
     revcount = shortlog and web.maxshortchanges or web.maxchanges
     if 'revcount' in req.form:
@@ -246,9 +245,7 @@
 
     count = len(web.repo)
     pos = ctx.rev()
-    start = max(0, pos - revcount + 1)
-    end = pos + 1
-    parity = paritygen(web.stripecount, offset=start - end)
+    parity = paritygen(web.stripecount)
 
     changenav = webutil.revnav(web.repo).gen(pos, revcount, count)