dirstate.walk: factor out directory traversal

This function will be used in upcoming patches.

mercurial/dirstate.py

@@ -754,9 +754,10 b' class dirstate(object):'
 
         skipstep3 = skipstep3 and not (work or dirsnotfound)
         work = [d for d in work if not dirignore(d[0])]
-        wadd = work.append
 
         # step 2: visit subdirectories
+        def traverse(work):
+            wadd = work.append
         while work:
             nd, d = work.pop()
             skip = None
@@ -774,10 +775,11 b' class dirstate(object):'
                 raise
             for f, kind, st in entries:
                 if normalizefile:
-                    # even though f might be a directory, we're only interested
-                    # in comparing it to files currently in the dmap --
-                    # therefore normalizefile is enough
-                    nf = normalizefile(nd and (nd + "/" + f) or f, True, True)
+                        # even though f might be a directory, we're only
+                        # interested in comparing it to files currently in the
+                        # dmap -- therefore normalizefile is enough
+                        nf = normalizefile(nd and (nd + "/" + f) or f, True,
+                                           True)
                     f = d and (d + "/" + f) or f
                 else:
                     nf = nd and (nd + "/" + f) or f
@@ -799,6 +801,8 b' class dirstate(object):'
                     elif nf in dmap and (matchalways or matchfn(nf)):
                         results[nf] = None
 
+        traverse(work)
+
         for s in subrepos:
             del results[s]
         del results['.hg']