rework all code using tags

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

rework all code using tags

Add three utility functions:

tags(): get (and possibly load) the tags mapping
tagslist(): sort tag,node by revision (aka topologically)
nodetags(): return a list of tags associated with a node (also cached)

Update all the code using tags to use these.

Simplify identify code
 make unknown always visible if printed
 don't ignore tip pseudo-tag

manifest hash: e6deb4d545ad465be7735f9ec43227bcb5e238c7
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.0 (GNU/Linux)

iD8DBQFCr+HjywK+sNU5EO8RAh4/AJ90cI0WxmvQAj6Lq2ZiG8LmqZan/QCfR8B5
ltu8tOIEHDa8LhfS9wtBu0k=
=pv3t
-----END PGP SIGNATURE-----

mercurial/commands.py

@@ -126,18 +126,6 @@ def show_changeset(ui, repo, rev=0, changenode=None, filelog=None):
             ui.status("summary:     %s\n" % description[0])
     ui.status("\n")
 
-def tags_load(repo):
-    repo.lookup(0) # prime the cache
-    i = repo.tags.items()
-    n = []
-    for e in i:
-        try:
-            l = repo.changelog.rev(e[1])
-        except KeyError:
-            l = -2
-        n.append((l, e))
-    return n
-
 def help(ui, cmd=None):
     '''show help for a given command or all commands'''
     if cmd:
@@ -328,17 +316,15 @@ def identify(ui, repo):
     """print information about the working copy"""
     (c, a, d, u) = repo.diffdir(repo.root)
     mflag = (c or a or d or u) and "+" or ""
-    parents = [parent for parent in repo.dirstate.parents()
-                      if parent != hg.nullid]
+    parents = [p for p in repo.dirstate.parents() if p != hg.nullid]
     if not parents:
-        ui.note("unknown\n")
+        ui.write("unknown\n")
         return
 
     tstring = ''
     if not ui.quiet:
-        taglist = [e[1] for e in tags_load(repo)]
-        tstring = " %s" % ' + '.join([e[0] for e in taglist
-                                      if e[0] != 'tip' and e[1] in parents])
+        tags = sum(map(repo.nodetags, parents), [])
+        tstring = " " + ' + '.join(tags)
 
     hexfunc = ui.verbose and hg.hex or hg.short
     pstring = '+'.join([hexfunc(parent) for parent in parents])
@@ -544,17 +530,15 @@ def status(ui, repo):
 
 def tags(ui, repo):
     """list repository tags"""
-    n = tags_load(repo)
-
-    n.sort()
-    n.reverse()
-    i = [ e[1] for e in n ]
-    for k, n in i:
+    
+    l = repo.tagslist()
+    l.reverse()
+    for t,n in l:
         try:
             r = repo.changelog.rev(n)
         except KeyError:
             r = "?"
-        print "%-30s %5d:%s" % (k, repo.changelog.rev(n), hg.hex(n))
+        print "%-30s %5d:%s" % (t, repo.changelog.rev(n), hg.hex(n))
 
 def tip(ui, repo):
     """show the tip revision"""

mercurial/hg.py

@@ -334,7 +334,8 @@ class localrepository:
         self.manifest = manifest(self.opener)
         self.changelog = changelog(self.opener)
         self.ignorelist = None
-        self.tags = None
+        self.tagscache = None
+        self.nodetagscache = None
 
         if not self.remote:
             self.dirstate = dirstate(self.opener, ui, self.root)
@@ -355,9 +356,10 @@ class localrepository:
             if pat.search(f): return True
         return False
 
-    def lookup(self, key):
-        if self.tags is None:
-            self.tags = {}
+    def tags(self):
+        '''return a mapping of tag to node'''
+        if not self.tagscache: 
+            self.tagscache = {}
             try:
                 # read each head of the tags file, ending with the tip
                 # and add each tag found to the map, with "newer" ones
@@ -369,11 +371,35 @@ class localrepository:
                     for l in fl.revision(r).splitlines():
                         if l:
                             n, k = l.split(" ")
-                            self.tags[k] = bin(n)
+                            self.tagscache[k] = bin(n)
             except KeyError: pass
-            self.tags['tip'] = self.changelog.tip()
+            self.tagscache['tip'] = self.changelog.tip()
+
+        return self.tagscache
+
+    def tagslist(self):
+        '''return a list of tags ordered by revision'''
+        l = []
+        for t,n in self.tags().items():
+            try:
+                r = self.changelog.rev(n)
+            except:
+                r = -2 # sort to the beginning of the list if unknown
+            l.append((r,t,n))
+        l.sort()
+        return [(t,n) for r,t,n in l]
+
+    def nodetags(self, node):
+        '''return the tags associated with a node'''
+        if not self.nodetagscache:
+            self.nodetagscache = {}
+            for t,n in self.tags().items():
+                self.nodetagscache.setdefault(n,[]).append(t)
+        return self.nodetagscache.get(node, [])
+
+    def lookup(self, key):
         try:
-            return self.tags[key]
+            return self.tags()[key]
         except KeyError:
             return self.changelog.lookup(key)
 

mercurial/hgweb.py

@@ -523,12 +523,8 @@ class hgweb:
         cl = self.repo.changelog
         mf = cl.read(cl.tip())[0]
 
-        self.repo.lookup(0) # prime the cache
-        i = self.repo.tags.items()
-        n = [ (cl.rev(e[1]), e) for e in i ] # sort by revision
-        n.sort()
-        n.reverse()
-        i = [ e[1] for e in n ]
+        i = self.repo.tagslist()
+        i.reverse()
 
         def entries():
             parity = 0