view tests/test-shelve.t @ 25703:1a6a117d0b95

import-checker: establish modern import convention

We introduce a new convention for declaring imports and enforce it via
the import checker script.

The new convention is only active when absolute imports are used, which is
currently nowhere. Keying off "from __future__ import absolute_import" to
engage the new import convention seems like the easiest solution. It is
also beneficial for Mercurial to use this mode because it means less work
and ambiguity for the importer and potentially better performance due to
fewer stat() system calls because the importer won't look for modules in
relative paths unless explicitly asked.

Once all files are converted to use absolute import, we can refactor
this code to again only have a single import convention and we can
require use of absolute import in the style checker.

The rules for the new convention are documented in the docstring of the
added function. Tests have been added to test-module-imports.t. Some
tests are sensitive to newlines and source column position, which makes
docstring testing difficult and/or impossible.

  $ cat <<EOF >> $HGRCPATH
  > [extensions]
  > mq =
  > shelve =
  > [defaults]
  > diff = --nodates --git
  > qnew = --date '0 0'
  > EOF

  $ hg init repo
  $ cd repo
  $ mkdir a b
  $ echo a > a/a
  $ echo b > b/b
  $ echo c > c
  $ echo d > d
  $ echo x > x
  $ hg addremove -q

shelve has a help message
  $ hg shelve -h
  hg shelve [OPTION]... [FILE]...
  
  save and set aside changes from the working directory
  
      Shelving takes files that "hg status" reports as not clean, saves the
      modifications to a bundle (a shelved change), and reverts the files so
      that their state in the working directory becomes clean.
  
      To restore these changes to the working directory, using "hg unshelve";
      this will work even if you switch to a different commit.
  
      When no files are specified, "hg shelve" saves all not-clean files. If
      specific files or directories are named, only changes to those files are
      shelved.
  
      Each shelved change has a name that makes it easier to find later. The
      name of a shelved change defaults to being based on the active bookmark,
      or if there is no active bookmark, the current named branch.  To specify a
      different name, use "--name".
  
      To see a list of existing shelved changes, use the "--list" option. For
      each shelved change, this will print its name, age, and description; use "
      --patch" or "--stat" for more details.
  
      To delete specific shelved changes, use "--delete". To delete all shelved
      changes, use "--cleanup".
  
  (use "hg help -e shelve" to show help for the shelve extension)
  
  options ([+] can be repeated):
  
   -A --addremove           mark new/missing files as added/removed before
                            shelving
      --cleanup             delete all shelved changes
      --date DATE           shelve with the specified commit date
   -d --delete              delete the named shelved change(s)
   -e --edit                invoke editor on commit messages
   -l --list                list current shelves
   -m --message TEXT        use text as shelve message
   -n --name NAME           use the given name for the shelved commit
   -p --patch               show patch
   -i --interactive         interactive mode, only works while creating a shelve
      --stat                output diffstat-style summary of changes
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
      --mq                  operate on patch repository
  
  (some details hidden, use --verbose to show complete help)

shelving in an empty repo should be possible
(this tests also that editor is not invoked, if '--edit' is not
specified)

  $ HGEDITOR=cat hg shelve
  shelved as default
  0 files updated, 0 files merged, 5 files removed, 0 files unresolved

  $ hg unshelve
  unshelving change 'default'

  $ hg commit -q -m 'initial commit'

  $ hg shelve
  nothing changed
  [1]

create an mq patch - shelving should work fine with a patch applied

  $ echo n > n
  $ hg add n
  $ hg commit n -m second
  $ hg qnew second.patch

shelve a change that we will delete later

  $ echo a >> a/a
  $ hg shelve
  shelved as default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

set up some more complex changes to shelve

  $ echo a >> a/a
  $ hg mv b b.rename
  moving b/b to b.rename/b (glob)
  $ hg cp c c.copy
  $ hg status -C
  M a/a
  A b.rename/b
    b/b
  A c.copy
    c
  R b/b

prevent some foot-shooting

  $ hg shelve -n foo/bar
  abort: shelved change names may not contain slashes
  [255]
  $ hg shelve -n .baz
  abort: shelved change names may not start with '.'
  [255]

the common case - no options or filenames

  $ hg shelve
  shelved as default-01
  2 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ hg status -C

ensure that our shelved changes exist

  $ hg shelve -l
  default-01      (*)* changes to '[mq]: second.patch' (glob)
  default         (*)* changes to '[mq]: second.patch' (glob)

  $ hg shelve -l -p default
  default         (*)* changes to '[mq]: second.patch' (glob)
  
  diff --git a/a/a b/a/a
  --- a/a/a
  +++ b/a/a
  @@ -1,1 +1,2 @@
   a
  +a

  $ hg shelve --list --addremove
  abort: options '--list' and '--addremove' may not be used together
  [255]

delete our older shelved change

  $ hg shelve -d default
  $ hg qfinish -a -q

local edits should not prevent a shelved change from applying

  $ printf "z\na\n" > a/a
  $ hg unshelve --keep
  unshelving change 'default-01'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 4:4702e8911fe0 "changes to '[mq]: second.patch'" (tip)
  merging a/a

  $ hg revert --all -q
  $ rm a/a.orig b.rename/b c.copy

apply it and make sure our state is as expected

  $ hg unshelve
  unshelving change 'default-01'
  $ hg status -C
  M a/a
  A b.rename/b
    b/b
  A c.copy
    c
  R b/b
  $ hg shelve -l

  $ hg unshelve
  abort: no shelved changes to apply!
  [255]
  $ hg unshelve foo
  abort: shelved change 'foo' not found
  [255]

named shelves, specific filenames, and "commit messages" should all work
(this tests also that editor is invoked, if '--edit' is specified)

  $ hg status -C
  M a/a
  A b.rename/b
    b/b
  A c.copy
    c
  R b/b
  $ HGEDITOR=cat hg shelve -q -n wibble -m wat -e a
  wat
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: shelve@localhost
  HG: branch 'default'
  HG: changed a/a

expect "a" to no longer be present, but status otherwise unchanged

  $ hg status -C
  A b.rename/b
    b/b
  A c.copy
    c
  R b/b
  $ hg shelve -l --stat
  wibble          (*)    wat (glob)
   a/a |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)

and now "a/a" should reappear

  $ cd a
  $ hg unshelve -q wibble
  $ cd ..
  $ hg status -C
  M a/a
  A b.rename/b
    b/b
  A c.copy
    c
  R b/b

cause unshelving to result in a merge with 'a' conflicting

  $ hg shelve -q
  $ echo c>>a/a
  $ hg commit -m second
  $ hg tip --template '{files}\n'
  a/a

add an unrelated change that should be preserved

  $ mkdir foo
  $ echo foo > foo/foo
  $ hg add foo/foo

force a conflicted merge to occur

  $ hg unshelve
  unshelving change 'default'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 5:4702e8911fe0 "changes to '[mq]: second.patch'" (tip)
  merging a/a
  warning: conflicts during merge.
  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
  [1]

ensure that we have a merge with unresolved conflicts

  $ hg heads -q --template '{rev}\n'
  5
  4
  $ hg parents -q --template '{rev}\n'
  4
  5
  $ hg status
  M a/a
  M b.rename/b
  M c.copy
  R b/b
  ? a/a.orig
  $ hg diff
  diff --git a/a/a b/a/a
  --- a/a/a
  +++ b/a/a
  @@ -1,2 +1,6 @@
   a
  +<<<<<<< dest:   *  - shelve: pending changes temporary commit (glob)
   c
  +=======
  +a
  +>>>>>>> source: 4702e8911fe0 - shelve: changes to '[mq]: second.patch'
  diff --git a/b/b b/b.rename/b
  rename from b/b
  rename to b.rename/b
  diff --git a/c b/c.copy
  copy from c
  copy to c.copy
  $ hg resolve -l
  U a/a

  $ hg shelve
  abort: unshelve already in progress
  (use 'hg unshelve --continue' or 'hg unshelve --abort')
  [255]

abort the unshelve and be happy

  $ hg status
  M a/a
  M b.rename/b
  M c.copy
  R b/b
  ? a/a.orig
  $ hg unshelve -a
  rebase aborted
  unshelve of 'default' aborted
  $ hg heads -q
  3:2e69b451d1ea
  $ hg parents
  changeset:   3:2e69b451d1ea
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     second
  
  $ hg resolve -l
  $ hg status
  A foo/foo
  ? a/a.orig

try to continue with no unshelve underway

  $ hg unshelve -c
  abort: no unshelve operation underway
  [255]
  $ hg status
  A foo/foo
  ? a/a.orig

redo the unshelve to get a conflict

  $ hg unshelve -q
  warning: conflicts during merge.
  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
  [1]

attempt to continue

  $ hg unshelve -c
  abort: unresolved conflicts, can't continue
  (see 'hg resolve', then 'hg unshelve --continue')
  [255]

  $ hg revert -r . a/a
  $ hg resolve -m a/a
  (no more unresolved files)

  $ hg commit -m 'commit while unshelve in progress'
  abort: unshelve already in progress
  (use 'hg unshelve --continue' or 'hg unshelve --abort')
  [255]

  $ hg unshelve -c
  rebasing 5:4702e8911fe0 "changes to '[mq]: second.patch'" (tip)
  unshelve of 'default' complete

ensure the repo is as we hope

  $ hg parents
  changeset:   3:2e69b451d1ea
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     second
  
  $ hg heads -q
  3:2e69b451d1ea

  $ hg status -C
  A b.rename/b
    b/b
  A c.copy
    c
  A foo/foo
  R b/b
  ? a/a.orig

there should be no shelves left

  $ hg shelve -l

#if execbit

ensure that metadata-only changes are shelved

  $ chmod +x a/a
  $ hg shelve -q -n execbit a/a
  $ hg status a/a
  $ hg unshelve -q execbit
  $ hg status a/a
  M a/a
  $ hg revert a/a

#endif

#if symlink

  $ rm a/a
  $ ln -s foo a/a
  $ hg shelve -q -n symlink a/a
  $ hg status a/a
  $ hg unshelve -q symlink
  $ hg status a/a
  M a/a
  $ hg revert a/a

#endif

set up another conflict between a commit and a shelved change

  $ hg revert -q -C -a
  $ rm a/a.orig b.rename/b c.copy
  $ echo a >> a/a
  $ hg shelve -q
  $ echo x >> a/a
  $ hg ci -m 'create conflict'
  $ hg add foo/foo

if we resolve a conflict while unshelving, the unshelve should succeed

  $ HGMERGE=true hg unshelve
  unshelving change 'default'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 6:c5e6910e7601 "changes to 'second'" (tip)
  merging a/a
  note: rebase of 6:c5e6910e7601 created no changes to commit
  $ hg parents -q
  4:33f7f61e6c5e
  $ hg shelve -l
  $ hg status
  A foo/foo
  $ cat a/a
  a
  c
  x

test keep and cleanup

  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg shelve --list
  default         (*)    changes to 'create conflict' (glob)
  $ hg unshelve --keep
  unshelving change 'default'
  $ hg shelve --list
  default         (*)    changes to 'create conflict' (glob)
  $ hg shelve --cleanup
  $ hg shelve --list

  $ hg shelve --cleanup --delete
  abort: options '--cleanup' and '--delete' may not be used together
  [255]
  $ hg shelve --cleanup --patch
  abort: options '--cleanup' and '--patch' may not be used together
  [255]
  $ hg shelve --cleanup --message MESSAGE
  abort: options '--cleanup' and '--message' may not be used together
  [255]

test bookmarks

  $ hg bookmark test
  $ hg bookmark
   * test                      4:33f7f61e6c5e
  $ hg shelve
  shelved as test
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg bookmark
   * test                      4:33f7f61e6c5e
  $ hg unshelve
  unshelving change 'test'
  $ hg bookmark
   * test                      4:33f7f61e6c5e

shelve should still work even if mq is disabled

  $ hg --config extensions.mq=! shelve
  shelved as test
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg --config extensions.mq=! shelve --list
  test            (*)    changes to 'create conflict' (glob)
  $ hg --config extensions.mq=! unshelve
  unshelving change 'test'

shelve should leave dirstate clean (issue4055)

  $ cd ..
  $ hg init shelverebase
  $ cd shelverebase
  $ printf 'x\ny\n' > x
  $ echo z > z
  $ hg commit -Aqm xy
  $ echo z >> x
  $ hg commit -Aqm z
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ printf 'a\nx\ny\nz\n' > x
  $ hg commit -Aqm xyz
  $ echo c >> z
  $ hg shelve
  shelved as default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg rebase -d 1 --config extensions.rebase=
  rebasing 2:323bfa07f744 "xyz" (tip)
  merging x
  saved backup bundle to $TESTTMP/shelverebase/.hg/strip-backup/323bfa07f744-78114325-backup.hg (glob)
  $ hg unshelve
  unshelving change 'default'
  rebasing shelved changes
  rebasing 4:b8fefe789ed0 "changes to 'xyz'" (tip)
  $ hg status
  M z

  $ cd ..

shelve should only unshelve pending changes (issue4068)

  $ hg init onlypendingchanges
  $ cd onlypendingchanges
  $ touch a
  $ hg ci -Aqm a
  $ touch b
  $ hg ci -Aqm b
  $ hg up -q 0
  $ touch c
  $ hg ci -Aqm c

  $ touch d
  $ hg add d
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg up -q 1
  $ hg unshelve
  unshelving change 'default'
  rebasing shelved changes
  rebasing 3:0cae6656c016 "changes to 'c'" (tip)
  $ hg status
  A d

unshelve should work on an ancestor of the original commit

  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg up 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg unshelve
  unshelving change 'default'
  rebasing shelved changes
  rebasing 3:be58f65f55fb "changes to 'b'" (tip)
  $ hg status
  A d

test bug 4073 we need to enable obsolete markers for it

  $ cat >> $HGRCPATH << EOF
  > [experimental]
  > evolution=createmarkers
  > EOF
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg debugobsolete `hg --debug id -i -r 1`
  $ hg unshelve
  unshelving change 'default'

unshelve should leave unknown files alone (issue4113)

  $ echo e > e
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg status
  ? e
  $ hg unshelve
  unshelving change 'default'
  $ hg status
  A d
  ? e
  $ cat e
  e

unshelve should keep a copy of unknown files

  $ hg add e
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ echo z > e
  $ hg unshelve
  unshelving change 'default'
  $ cat e
  e
  $ cat e.orig
  z


unshelve and conflicts with tracked and untracked files

 preparing:

  $ rm *.orig
  $ hg ci -qm 'commit stuff'
  $ hg phase -p null:

 no other changes - no merge:

  $ echo f > f
  $ hg add f
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo g > f
  $ hg unshelve
  unshelving change 'default'
  $ hg st
  A f
  ? f.orig
  $ cat f
  f
  $ cat f.orig
  g

 other uncommitted changes - merge:

  $ hg st
  A f
  ? f.orig
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg log -G --template '{rev}  {desc|firstline}  {author}' -R bundle://.hg/shelved/default.hg -r 'bundle()'
  o  4  changes to 'commit stuff'  shelve@localhost
  |
  $ hg log -G --template '{rev}  {desc|firstline}  {author}'
  @  3  commit stuff  test
  |
  | o  2  c  test
  |/
  o  0  a  test
  
  $ mv f.orig f
  $ echo 1 > a
  $ hg unshelve --date '1073741824 0'
  unshelving change 'default'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 5:23b29cada8ba "changes to 'commit stuff'" (tip)
  merging f
  warning: conflicts during merge.
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
  [1]
  $ hg log -G --template '{rev}  {desc|firstline}  {author}  {date|isodate}'
  @  5  changes to 'commit stuff'  shelve@localhost  1970-01-01 00:00 +0000
  |
  | @  4  pending changes temporary commit  shelve@localhost  2004-01-10 13:37 +0000
  |/
  o  3  commit stuff  test  1970-01-01 00:00 +0000
  |
  | o  2  c  test  1970-01-01 00:00 +0000
  |/
  o  0  a  test  1970-01-01 00:00 +0000
  
  $ hg st
  M f
  ? f.orig
  $ cat f
  <<<<<<< dest:   5f6b880e719b  - shelve: pending changes temporary commit
  g
  =======
  f
  >>>>>>> source: 23b29cada8ba - shelve: changes to 'commit stuff'
  $ cat f.orig
  g
  $ hg unshelve --abort
  rebase aborted
  unshelve of 'default' aborted
  $ hg st
  M a
  ? f.orig
  $ cat f.orig
  g
  $ hg unshelve
  unshelving change 'default'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 5:23b29cada8ba "changes to 'commit stuff'" (tip)
  $ hg st
  M a
  A f
  ? f.orig

 other committed changes - merge:

  $ hg shelve f
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg ci a -m 'intermediate other change'
  $ mv f.orig f
  $ hg unshelve
  unshelving change 'default'
  rebasing shelved changes
  rebasing 5:23b29cada8ba "changes to 'commit stuff'" (tip)
  merging f
  warning: conflicts during merge.
  merging f incomplete! (edit conflicts, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
  [1]
  $ hg st
  M f
  ? f.orig
  $ cat f
  <<<<<<< dest:   *  - test: intermediate other change (glob)
  g
  =======
  f
  >>>>>>> source: 23b29cada8ba - shelve: changes to 'commit stuff'
  $ cat f.orig
  g
  $ hg unshelve --abort
  rebase aborted
  unshelve of 'default' aborted
  $ hg st
  ? f.orig
  $ cat f.orig
  g
  $ hg shelve --delete default

Recreate some conflict again

  $ cd ../repo
  $ hg up -C -r 3
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (leaving bookmark test)
  $ echo y >> a/a
  $ hg shelve
  shelved as default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg up test
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (activating bookmark test)
  $ hg unshelve
  unshelving change 'default'
  rebasing shelved changes
  rebasing 5:4b555fdb4e96 "changes to 'second'" (tip)
  merging a/a
  warning: conflicts during merge.
  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
  [1]

Test that resolving all conflicts in one direction (so that the rebase
is a no-op), works (issue4398)

  $ hg revert -a -r .
  reverting a/a (glob)
  $ hg resolve -m a/a
  (no more unresolved files)
  $ hg unshelve -c
  rebasing 5:4b555fdb4e96 "changes to 'second'" (tip)
  note: rebase of 5:4b555fdb4e96 created no changes to commit
  unshelve of 'default' complete
  $ hg diff
  $ hg status
  ? a/a.orig
  ? foo/foo
  $ hg summary
  parent: 4:33f7f61e6c5e tip
   create conflict
  branch: default
  bookmarks: *test
  commit: 2 unknown (clean)
  update: (current)
  phases: 5 draft

  $ hg shelve --delete --stat
  abort: options '--delete' and '--stat' may not be used together
  [255]
  $ hg shelve --delete --name NAME
  abort: options '--delete' and '--name' may not be used together
  [255]

Test interactive shelve
  $ cat <<EOF >> $HGRCPATH
  > [ui]
  > interactive = true
  > EOF
  $ echo 'a' >> a/b
  $ cat a/a >> a/b
  $ echo 'x' >> a/b
  $ mv a/b a/a
  $ echo 'a' >> foo/foo
  $ hg st
  M a/a
  ? a/a.orig
  ? foo/foo
  $ cat a/a
  a
  a
  c
  x
  x
  $ cat foo/foo
  foo
  a
  $ hg shelve --interactive << EOF
  > y
  > y
  > n
  > EOF
  diff --git a/a/a b/a/a
  2 hunks, 2 lines changed
  examine changes to 'a/a'? [Ynesfdaq?] y
  
  @@ -1,3 +1,4 @@
  +a
   a
   c
   x
  record change 1/2 to 'a/a'? [Ynesfdaq?] y
  
  @@ -1,3 +2,4 @@
   a
   c
   x
  +x
  record change 2/2 to 'a/a'? [Ynesfdaq?] n
  
  shelved as test
  merging a/a
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  $ cat a/a
  a
  c
  x
  x
  $ cat foo/foo
  foo
  a
  $ hg st
  M a/a
  ? foo/foo
  $ hg unshelve
  unshelving change 'test'
  temporarily committing pending changes (restore with 'hg unshelve --abort')
  rebasing shelved changes
  rebasing 6:65b5d1c34c34 "changes to 'create conflict'" (tip)
  merging a/a
  $ cat a/a
  a
  a
  c
  x
  x

shelve --patch and shelve --stat should work with a single valid shelfname

  $ hg up --clean .
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg shelve --list
  $ echo 'patch a' > shelf-patch-a
  $ hg add shelf-patch-a
  $ hg shelve
  shelved as default
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo 'patch b' > shelf-patch-b
  $ hg add shelf-patch-b
  $ hg shelve
  shelved as default-01
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg shelve --patch default default-01
  abort: --patch expects a single shelf
  [255]
  $ hg shelve --stat default default-01
  abort: --stat expects a single shelf
  [255]
  $ hg shelve --patch default
  default         (* ago)    changes to 'create conflict' (glob)
  
  diff --git a/shelf-patch-a b/shelf-patch-a
  new file mode 100644
  --- /dev/null
  +++ b/shelf-patch-a
  @@ -0,0 +1,1 @@
  +patch a
  $ hg shelve --stat default
  default         (* ago)    changes to 'create conflict' (glob)
   shelf-patch-a |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  $ hg shelve --patch nonexistentshelf
  abort: cannot find shelf nonexistentshelf
  [255]
  $ hg shelve --stat nonexistentshelf
  abort: cannot find shelf nonexistentshelf
  [255]