view tests/test-mq-header-from.t @ 26631:e077ce385609

localrepo: restore dirstate to one before rollbacking if not parent-gone

'localrepository.rollback()' explicilty restores dirstate, only if at
least one of current parents of the working directory is removed at
rollbacking (a.k.a "parent-gone").

After DirstateTransactionPlan, 'dirstate.write()' will cause marking
'.hg/dirstate' as a file to be restored at rollbacking.

    https://mercurial.selenic.com/wiki/DirstateTransactionPlan

Then, 'transaction.rollback()' restores '.hg/dirstate' regardless of
parents of the working directory at that time, and this causes
unexpected dirstate changes if not "parent-gone" (e.g.  "hg update" to
another branch after "hg commit" or so, then "hg rollback").

To avoid such situation, this patch restores dirstate to one before
rollbacking if not "parent-gone".

  before:
    b1. restore dirstate explicitly, if "parent-gone"

  after:
    a1. save dirstate before actual rollbacking via dirstateguard
    a2. restore dirstate via 'transaction.rollback()'
    a3. if "parent-gone"
        - discard backup (a1)
        - restore dirstate from 'undo.dirstate'
    a4. otherwise, restore dirstate from backup (a1)

Even though restoring dirstate at (a3) after (a2) seems redundant,
this patch keeps this existing code path, because:

  - it isn't ensured that 'dirstate.write()' was invoked at least once
    while transaction running

    If not, '.hg/dirstate' isn't restored at (a2).

    In addition to it, rude 3rd party extension invoking
    'dirstate.write()' without 'repo' while transaction running (see
    subsequent patches for detail) may break consistency of a file
    backup-ed by transaction.

  - this patch mainly focuses on changes for DirstateTransactionPlan

    Restoring dirstate at (a3) itself should be cheaper enough than
    rollbacking itself. Redundancy will be removed in next step.

Newly added test is almost meaningless at this point. It will be used
to detect regression while implementing delayed dirstate write out.

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH
  $ echo "[diff]" >> $HGRCPATH
  $ echo "nodates=true" >> $HGRCPATH
  $ catlog() {
  >     cat .hg/patches/$1.patch | sed -e "s/^diff \-r [0-9a-f]* /diff -r ... /" \
  >                                    -e "s/^\(# Parent \).*/\1/"
  >     hg log --template "{rev}: {desc} - {author}\n"
  > }
  $ runtest() {
  >     echo ==== init
  >     hg init a
  >     cd a
  >     hg qinit
  > 
  > 
  >     echo ==== qnew -U
  >     hg qnew -U 1.patch
  >     catlog 1
  > 
  >     echo ==== qref
  >     echo "1" >1
  >     hg add
  >     hg qref
  >     catlog 1
  > 
  >     echo ==== qref -u
  >     hg qref -u mary
  >     catlog 1
  > 
  >     echo ==== qnew
  >     hg qnew 2.patch
  >     echo "2" >2
  >     hg add
  >     hg qref
  >     catlog 2
  > 
  >     echo ==== qref -u
  >     hg qref -u jane
  >     catlog 2
  > 
  > 
  >     echo ==== qnew -U -m
  >     hg qnew -U -m "Three" 3.patch
  >     catlog 3
  > 
  >     echo ==== qref
  >     echo "3" >3
  >     hg add
  >     hg qref
  >     catlog 3
  > 
  >     echo ==== qref -m
  >     hg qref -m "Drei"
  >     catlog 3
  > 
  >     echo ==== qref -u
  >     hg qref -u mary
  >     catlog 3
  > 
  >     echo ==== qref -u -m
  >     hg qref -u maria -m "Three (again)"
  >     catlog 3
  > 
  >     echo ==== qnew -m
  >     hg qnew -m "Four" 4.patch
  >     echo "4" >4of t
  >     hg add
  >     hg qref
  >     catlog 4
  > 
  >     echo ==== qref -u
  >     hg qref -u jane
  >     catlog 4
  > 
  > 
  >     echo ==== qnew with HG header
  >     hg qnew --config 'mq.plain=true' 5.patch
  >     hg qpop
  >     echo "# HG changeset patch" >>.hg/patches/5.patch
  >     echo "# User johndoe" >>.hg/patches/5.patch
  >     hg qpush 2>&1 | grep 'now at'
  >     catlog 5
  > 
  >     echo ==== hg qref
  >     echo "5" >5
  >     hg add
  >     hg qref
  >     catlog 5
  > 
  >     echo ==== hg qref -U
  >     hg qref -U
  >     catlog 5
  > 
  >     echo ==== hg qref -u
  >     hg qref -u johndeere
  >     catlog 5
  > 
  > 
  >     echo ==== qnew with plain header
  >     hg qnew --config 'mq.plain=true' -U 6.patch
  >     hg qpop
  >     hg qpush 2>&1 | grep 'now at'
  >     catlog 6
  > 
  >     echo ==== hg qref
  >     echo "6" >6
  >     hg add
  >     hg qref
  >     catlog 6
  > 
  >     echo ==== hg qref -U
  >     hg qref -U
  >     catlog 6
  > 
  >     echo ==== hg qref -u
  >     hg qref -u johndeere
  >     catlog 6
  > 
  > 
  >     echo ==== "qpop -a / qpush -a"
  >     hg qpop -a
  >     hg qpush -a
  >     hg log --template "{rev}: {desc} - {author}\n"
  > }

======= plain headers

  $ echo "[mq]" >> $HGRCPATH
  $ echo "plain=true" >> $HGRCPATH
  $ mkdir sandbox
  $ (cd sandbox ; runtest)
  ==== init
  ==== qnew -U
  From: test
  
  0: [mq]: 1.patch - test
  ==== qref
  adding 1
  From: test
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - test
  ==== qref -u
  From: mary
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - mary
  ==== qnew
  adding 2
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - test
  0: [mq]: 1.patch - mary
  ==== qref -u
  From: jane
  
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -U -m
  From: test
  
  Three
  
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref
  adding 3
  From: test
  
  Three
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -m
  From: test
  
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  From: mary
  
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - mary
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u -m
  From: maria
  
  Three (again)
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -m
  adding 4of
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - test
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  From: jane
  
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with HG header
  popping 5.patch
  now at: 4.patch
  now at: 5.patch
  # HG changeset patch
  # User johndoe
  4: imported patch 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 5
  # HG changeset patch
  # User johndoe
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  # HG changeset patch
  # User test
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - test
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  # HG changeset patch
  # User johndeere
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with plain header
  popping 6.patch
  now at: 5.patch
  now at: 6.patch
  From: test
  
  5: imported patch 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 6
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  From: johndeere
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - johndeere
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qpop -a / qpush -a
  popping 6.patch
  popping 5.patch
  popping 4.patch
  popping 3.patch
  popping 2.patch
  popping 1.patch
  patch queue now empty
  applying 1.patch
  applying 2.patch
  applying 3.patch
  applying 4.patch
  applying 5.patch
  applying 6.patch
  now at: 6.patch
  5: imported patch 6.patch - johndeere
  4: imported patch 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: imported patch 2.patch - jane
  0: imported patch 1.patch - mary
  $ rm -r sandbox

======= hg headers

  $ echo "plain=false" >> $HGRCPATH
  $ mkdir sandbox
  $ (cd sandbox ; runtest)
  ==== init
  ==== qnew -U
  # HG changeset patch
  # User test
  # Parent 
  
  0: [mq]: 1.patch - test
  ==== qref
  adding 1
  # HG changeset patch
  # User test
  # Parent 
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - test
  ==== qref -u
  # HG changeset patch
  # User mary
  # Parent 
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - mary
  ==== qnew
  adding 2
  # HG changeset patch
  # Parent 
  
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - test
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User jane
  # Parent 
  
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -U -m
  # HG changeset patch
  # User test
  # Parent 
  Three
  
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref
  adding 3
  # HG changeset patch
  # User test
  # Parent 
  Three
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -m
  # HG changeset patch
  # User test
  # Parent 
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User mary
  # Parent 
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - mary
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u -m
  # HG changeset patch
  # User maria
  # Parent 
  Three (again)
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -m
  adding 4of
  # HG changeset patch
  # Parent 
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - test
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User jane
  # Parent 
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with HG header
  popping 5.patch
  now at: 4.patch
  now at: 5.patch
  # HG changeset patch
  # User johndoe
  4: imported patch 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 5
  # HG changeset patch
  # User johndoe
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  # HG changeset patch
  # User test
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - test
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  # HG changeset patch
  # User johndeere
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with plain header
  popping 6.patch
  now at: 5.patch
  now at: 6.patch
  From: test
  
  5: imported patch 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 6
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  From: johndeere
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - johndeere
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qpop -a / qpush -a
  popping 6.patch
  popping 5.patch
  popping 4.patch
  popping 3.patch
  popping 2.patch
  popping 1.patch
  patch queue now empty
  applying 1.patch
  applying 2.patch
  applying 3.patch
  applying 4.patch
  applying 5.patch
  applying 6.patch
  now at: 6.patch
  5: imported patch 6.patch - johndeere
  4: imported patch 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: imported patch 2.patch - jane
  0: imported patch 1.patch - mary
  $ rm -r sandbox
  $ runtest
  ==== init
  ==== qnew -U
  # HG changeset patch
  # User test
  # Parent 
  
  0: [mq]: 1.patch - test
  ==== qref
  adding 1
  # HG changeset patch
  # User test
  # Parent 
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - test
  ==== qref -u
  # HG changeset patch
  # User mary
  # Parent 
  
  diff -r ... 1
  --- /dev/null
  +++ b/1
  @@ -0,0 +1,1 @@
  +1
  0: [mq]: 1.patch - mary
  ==== qnew
  adding 2
  # HG changeset patch
  # Parent 
  
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - test
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User jane
  # Parent 
  
  diff -r ... 2
  --- /dev/null
  +++ b/2
  @@ -0,0 +1,1 @@
  +2
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -U -m
  # HG changeset patch
  # User test
  # Parent 
  Three
  
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref
  adding 3
  # HG changeset patch
  # User test
  # Parent 
  Three
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -m
  # HG changeset patch
  # User test
  # Parent 
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - test
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User mary
  # Parent 
  Drei
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Drei - mary
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u -m
  # HG changeset patch
  # User maria
  # Parent 
  Three (again)
  
  diff -r ... 3
  --- /dev/null
  +++ b/3
  @@ -0,0 +1,1 @@
  +3
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew -m
  adding 4of
  # HG changeset patch
  # Parent 
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - test
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qref -u
  # HG changeset patch
  # User jane
  # Parent 
  Four
  
  diff -r ... 4of
  --- /dev/null
  +++ b/4of
  @@ -0,0 +1,1 @@
  +4 t
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with HG header
  popping 5.patch
  now at: 4.patch
  now at: 5.patch
  # HG changeset patch
  # User johndoe
  4: imported patch 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 5
  # HG changeset patch
  # User johndoe
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndoe
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  # HG changeset patch
  # User test
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - test
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  # HG changeset patch
  # User johndeere
  # Parent 
  
  diff -r ... 5
  --- /dev/null
  +++ b/5
  @@ -0,0 +1,1 @@
  +5
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qnew with plain header
  popping 6.patch
  now at: 5.patch
  now at: 6.patch
  From: test
  
  5: imported patch 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref
  adding 6
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -U
  From: test
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - test
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== hg qref -u
  From: johndeere
  
  diff -r ... 6
  --- /dev/null
  +++ b/6
  @@ -0,0 +1,1 @@
  +6
  5: [mq]: 6.patch - johndeere
  4: [mq]: 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: [mq]: 2.patch - jane
  0: [mq]: 1.patch - mary
  ==== qpop -a / qpush -a
  popping 6.patch
  popping 5.patch
  popping 4.patch
  popping 3.patch
  popping 2.patch
  popping 1.patch
  patch queue now empty
  applying 1.patch
  applying 2.patch
  applying 3.patch
  applying 4.patch
  applying 5.patch
  applying 6.patch
  now at: 6.patch
  5: imported patch 6.patch - johndeere
  4: imported patch 5.patch - johndeere
  3: Four - jane
  2: Three (again) - maria
  1: imported patch 2.patch - jane
  0: imported patch 1.patch - mary

  $ cd ..