[PATCH 1 of 5] phases: change phase command change detection

[Durham Goode]

# HG changeset patch
# User Durham Goode <durham at fb.com>
# Date 1412706697 25200
#      Tue Oct 07 11:31:37 2014 -0700
# Node ID 21386e638281d3fe94138c5fb8ea6f6d7aa3a8cd
# Parent  a1eb21f5caea4366310e32aa85248791d5bbfa0c
phases: change phase command change detection

A future patch is going to make phase computation lazy, so the phase command can
no longer read and diff the entire phase list directly. This changes the phase
command to build it's own list for diff purposes.

diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -4854,7 +4854,9 @@ def phase(ui, repo, *revs, **opts):
             if not revs:
                 raise util.Abort(_('empty revision set'))
             nodes = [repo[r].node() for r in revs]
-            olddata = repo._phasecache.getphaserevs(repo)[:]
+            unfi = repo.unfiltered()
+            getphase = unfi._phasecache.phase
+            olddata = [getphase(unfi, r) for r in unfi]
             phases.advanceboundary(repo, tr, targetphase, nodes)
             if opts['force']:
                 phases.retractboundary(repo, tr, targetphase, nodes)
@@ -4865,9 +4867,9 @@ def phase(ui, repo, *revs, **opts):
             lock.release()
         # moving revision from public to draft may hide them
         # We have to check result on an unfiltered repository
-        unfi = repo.unfiltered()
-        newdata = repo._phasecache.getphaserevs(unfi)
-        changes = sum(o != newdata[i] for i, o in enumerate(olddata))
+        getphase = unfi._phasecache.phase
+        newdata = [getphase(unfi, r) for r in unfi]
+        changes = sum(newdata[r] != olddata[r] for r in unfi)
         cl = unfi.changelog
         rejected = [n for n in nodes
                     if newdata[cl.rev(n)] < targetphase]