tests/test-diffdir.t

sshpeer: only print out 'running ssh' messages in debug mode (BC)

Previously, if another command was run with --verbose, and for whatever reason
that invoked sshpeer, we'd get a 'running ssh' message from sshpeer. This extra
line would interfere with that command's output and cause dumb parsers to
break.

For example, hg annotate can be run with --verbose to get full usernames. This,
combined with the third-party remotefilelog extension which can cause ssh
connections to be created, leads to an extra 'running ssh' line that breaks
most parsers.

This patch is (BC) because hg pull --verbose will no longer print out exactly
what ssh command it is running.

No tests are affected by this change.

  $ hg init
  $ touch a
  $ hg add a
  $ hg ci -m "a"

  $ echo 123 > b
  $ hg add b
  $ hg diff --nodates
  diff -r 3903775176ed b
  --- /dev/null
  +++ b/b
  @@ -0,0 +1,1 @@
  +123

  $ hg diff --nodates -r tip
  diff -r 3903775176ed b
  --- /dev/null
  +++ b/b
  @@ -0,0 +1,1 @@
  +123

  $ echo foo > a
  $ hg diff --nodates
  diff -r 3903775176ed a
  --- a/a
  +++ b/a
  @@ -0,0 +1,1 @@
  +foo
  diff -r 3903775176ed b
  --- /dev/null
  +++ b/b
  @@ -0,0 +1,1 @@
  +123

  $ hg diff -r ""
  hg: parse error: empty query
  [255]
  $ hg diff -r tip -r ""
  hg: parse error: empty query
  [255]