hgweb: pass nodefunc to the revnav object

The issue between hgweb and filtering lay in this function. Moving it into the
object itself helps to abstract the erroneous bit.

mercurial/hgweb/webcommands.py

@@ -242,7 +242,7 b' def changelog(web, req, tmpl, shortlog=F'
     pos = end - 1
     parity = paritygen(web.stripecount, offset=start - end)
 
-    changenav = webutil.revnav().gen(pos, revcount, count, web.repo.changectx)
+    changenav = webutil.revnav(web.repo.changectx).gen(pos, revcount, count)
 
     return tmpl(shortlog and 'shortlog' or 'changelog', changenav=changenav,
                 node=ctx.hex(), rev=pos, changesets=count,
@@ -772,7 +772,7 b' def filelog(web, req, tmpl):'
             yield e
 
     nodefunc = lambda x: fctx.filectx(fileid=x)
-    nav = webutil.revnav().gen(end - 1, revcount, count, nodefunc)
+    nav = webutil.revnav(nodefunc).gen(end - 1, revcount, count)
     return tmpl("filelog", file=f, node=fctx.hex(), nav=nav,
                 entries=lambda **x: entries(latestonly=False, **x),
                 latestentry=lambda **x: entries(latestonly=True, **x),
@@ -851,7 +851,7 b' def graph(web, req, tmpl):'
 
     uprev = min(max(0, count - 1), rev + revcount)
     downrev = max(0, rev - revcount)
-    changenav = webutil.revnav().gen(pos, revcount, count, web.repo.changectx)
+    changenav = webutil.revnav(web.repo.changectx).gen(pos, revcount, count)
 
     dag = graphmod.dagwalker(web.repo, range(start, end)[::-1])
     tree = list(graphmod.colored(dag, web.repo))

mercurial/hgweb/webutil.py

@@ -41,13 +41,19 b' def _navseq(step, firststep=None):'
 
 class revnav(object):
 
-    def gen(self, pos, pagelen, limit, nodefunc):
+    def __init__(self, nodefunc):
+        """Navigation generation object
+
+        :nodefun: factory for a changectx from a revision
+        """
+        self.nodefunc = nodefunc
+
+    def gen(self, pos, pagelen, limit):
         """computes label and revision id for navigation link
 
         :pos: is the revision relative to which we generate navigation.
         :pagelen: the size of each navigation page
         :limit: how far shall we link
-        :nodefun: factory for a changectx from a revision
 
         The return is:
             - a single element tuple
@@ -63,13 +69,15 b' class revnav(object):'
             if f > limit:
                 break
             if pos + f < limit:
-                navafter.append(("+%d" % f, hex(nodefunc(pos + f).node())))
+                navafter.append(("+%d" % f,
+                                 hex(self.nodefunc(pos + f).node())))
             if pos - f >= 0:
-                navbefore.insert(0, ("-%d" % f, hex(nodefunc(pos - f).node())))
+                navbefore.insert(0, ("-%d" % f,
+                                     hex(self.nodefunc(pos - f).node())))
 
         navafter.append(("tip", "tip"))
         try:
-            navbefore.insert(0, ("(0)", hex(nodefunc(0).node())))
+            navbefore.insert(0, ("(0)", hex(self.nodefunc(0).node())))
         except error.RepoError:
             pass