commands: inline definition of localrepo.parents() and drop the method (API)

localrepo.parents() has relatively few users, and most of those were
actually implicitly looking at the wctx, which is now made explicit
via repo[None].

hgext/rebase.py

@@ -441,7 +441,7 b' def rebase(ui, repo, **opts):'
                                              targetancestors)
                 storestatus(repo, originalwd, target, state, collapsef, keepf,
                             keepbranchesf, external, activebookmark)
-                if len(repo.parents()) == 2:
+                if len(repo[None].parents()) == 2:
                     repo.ui.debug('resuming interrupted rebase\n')
                 else:
                     try:
@@ -930,7 +930,7 b' def restorestatus(repo):'
 def needupdate(repo, state):
     '''check whether we should `update --clean` away from a merge, or if
     somehow the working dir got forcibly updated, e.g. by older hg'''
-    parents = [p.rev() for p in repo.parents()]
+    parents = [p.rev() for p in repo[None].parents()]
 
     # Are we in a merge state at all?
     if len(parents) < 2:

mercurial/commands.py

@@ -1190,7 +1190,7 b' def branch(ui, repo, label=None, **opts)'
             ui.status(_('reset working directory to branch %s\n') % label)
         elif label:
             if not opts.get('force') and label in repo.branchmap():
-                if label not in [p.branch() for p in repo.parents()]:
+                if label not in [p.branch() for p in repo[None].parents()]:
                     raise error.Abort(_('a branch of the same name already'
                                        ' exists'),
                                      # i18n: "it" refers to an existing branch
@@ -1600,8 +1600,8 b' def commit(ui, repo, *pats, **opts):'
         if not bheads:
             raise error.Abort(_('can only close branch heads'))
         elif opts.get('amend'):
-            if repo.parents()[0].p1().branch() != branch and \
-                    repo.parents()[0].p2().branch() != branch:
+            if repo[None].parents()[0].p1().branch() != branch and \
+                    repo[None].parents()[0].p2().branch() != branch:
                 raise error.Abort(_('can only close branch heads'))
 
     if opts.get('amend'):
@@ -4545,7 +4545,7 b' def import_(ui, repo, patch1=None, *patc'
                 tr = repo.transaction('import')
             else:
                 dsguard = cmdutil.dirstateguard(repo, 'import')
-            parents = repo.parents()
+            parents = repo[None].parents()
             for patchurl in patches:
                 if patchurl == '-':
                     ui.status(_('applying patch from stdin\n'))
@@ -4565,7 +4565,7 b' def import_(ui, repo, patch1=None, *patc'
                         haspatch = True
                         ui.note(msg + '\n')
                     if update or opts.get('exact'):
-                        parents = repo.parents()
+                        parents = repo[None].parents()
                     else:
                         parents = [repo[node]]
                     if rej:

mercurial/localrepo.py

@@ -852,10 +852,6 b' class localrepository(object):'
     def changectx(self, changeid):
         return self[changeid]
 
-    def parents(self, changeid=None):
-        '''get list of changectxs for parents of changeid'''
-        return self[changeid].parents()
-
     def setparents(self, p1, p2=nullid):
         self.dirstate.beginparentchange()
         copies = self.dirstate.setparents(p1, p2)
@@ -1170,7 +1166,7 b' class localrepository(object):'
                         % self.dirstate.branch())
 
             self.dirstate.invalidate()
-            parents = tuple([p.rev() for p in self.parents()])
+            parents = tuple([p.rev() for p in self[None].parents()])
             if len(parents) > 1:
                 ui.status(_('working directory now based on '
                             'revisions %d and %d\n') % parents)