push: restore old behavior of default-push (issue5000)

This effectively backs out dceaef70e410 and 10917b062adf.

We can't handle "default-push" just like "default:pushurl" because it is a
stand-alone named path. Instead, I have two ideas to work around the issue:

 a. two defaults: getpath(dest, default=('default-push', 'default'))
 b. virtual path: getpath(dest, default=':default')

(a) is conservative approach and will have less trouble, but callers have
to specify they need "default-push" or "default". (b) generates hidden
":default" path from "default" and "default-push", and callers request
":default". This will require some tricks and won't work if there are
conflicting sub-options valid for both "pull" and "push".

I'll take (a) for default branch. This patch should NOT BE MERGED to default
except for tests because it would break handling of "pushurl" sub-option.

mercurial/commands.py

@@ -5394,11 +5394,13 b' def push(ui, repo, dest=None, **opts):'
                 # this lets simultaneous -r, -b options continue working
                 opts.setdefault('rev', []).append("null")
 
+    path = ui.paths.getpath(dest, default='default-push')
+    if not path:
     path = ui.paths.getpath(dest, default='default')
     if not path:
         raise error.Abort(_('default repository not configured!'),
                          hint=_('see the "path" section in "hg help config"'))
-    dest, branches = path.pushloc, (path.branch, opts.get('branch') or [])
+    dest, branches = path.loc, (path.branch, opts.get('branch') or [])
     ui.status(_('pushing to %s\n') % util.hidepassword(dest))
     revs, checkout = hg.addbranchrevs(repo, repo, branches, opts.get('rev'))
     other = hg.peer(repo, opts, dest)

tests/test-default-push.t

@@ -46,6 +46,14 b" Push should push to 'default-push' when "
   adding file changes
   added 1 changesets with 1 changes to 1 files
 
+But push should push to 'default' if explicitly specified (issue5000):
+
+  $ hg --cwd b push default
+  pushing to $TESTTMP/a (glob)
+  searching for changes
+  no changes found
+  [1]
+
 Push should push to 'default-push' when 'default' is not set
 
   $ hg -q clone a push-default-only