git-clean: Display more accurate delete messages

(1) Only print out the names of the files and directories that got
    actually deleted. Also do not mention that we are not removing
    directories when the user did not ask us to do so with '-d'.
(2) Show ignore message for skipped untracked git repositories.

Consider the following repo layout:

  test.git/
    |-- tracked_dir/
    |     |-- some_tracked_file
    |     |-- some_untracked_file
    |-- tracked_file
    |-- untracked_file
    |-- untracked_foo/
    |     |-- bar/
    |     |     |-- bar.txt
    |     |-- emptydir/
    |     |-- frotz.git/
    |           |-- frotz.tx
    |-- untracked_some.git/
          |-- some.txt

Suppose the user issues 'git clean -fd' from the test.git directory.

When -d option is used and untracked directory 'foo' contains a
subdirectory 'frotz.git' that is managed by a different git repository
therefore it will not be removed.

  $ git clean -fd
  Removing tracked_dir/some_untracked_file
  Removing untracked_file
  Removing untracked_foo/
  Removing untracked_some.git/

The message displayed to the user is slightly misleading. The foo/
directory has not been removed because of foo/frotz.git still exists.
On the other hand the subdirectories 'bar' and 'emptydir' have been
deleted but they're not mentioned anywhere. Also, untracked_some.git
has not been removed either.

This behaviour is the result of the way the deletion of untracked
directories are reported. In the current implementation they are
deleted recursively but only the name of the top most directory is
printed out. The calling function does not know about any
subdirectories that could not be removed during the recursion.

Improve the way the deleted directories are reported back to
the user:
  (1) Create a recursive delete function 'remove_dirs' in builtin/clean.c
      to run in both dry_run and delete modes with the delete logic as
      follows:
        (a) Check if the current directory to be deleted is an untracked
            git repository. If it is and --force --force option is not set
            do not touch this directory, print ignore message, set dir_gone
            flag to false for the caller and return.
        (b) Otherwise for each item in current directory:
              (i)   If current directory cannot be accessed, print warning,
                    set dir_gone flag to false and return.
              (ii)  If the item is a subdirectory recurse into it,
                    check for the returned value of the dir_gone flag.
                    If the subdirectory is gone, add the name of the deleted
                    directory to a list of successfully removed items 'dels'.
                    Else set the dir_gone flag as the current directory
                    cannot be removed because we have at least one subdirectory
                    hanging around.
              (iii) If it is a file try to remove it. If success add the
                    file name to the 'dels' list, else print error and set
                    dir_gone flag to false.
        (c) After we finished deleting all items in the current directory and
            the dir_gone flag is still true, remove the directory itself.
            If failed set the dir_gone flag to false.

        (d) If the current directory cannot be deleted because the dir_gone flag
            has been set to false, print out all the successfully deleted items
            for this directory from the 'dels' list.
        (e) We're done with the current directory, return.

  (2) Modify the cmd_clean() function to:
        (a) call the recursive delete function 'remove_dirs()' for each
            topmost directory it wants to remove
        (b) check for the returned value of dir_gone flag. If it's true
            print the name of the directory as being removed.

Consider the output of the improved version:

  $ git clean -fd
  Removing tracked_dir/some_untracked_file
  Removing untracked_file
  Skipping repository untracked_foo/frotz.git
  Removing untracked_foo/bar
  Removing untracked_foo/emptydir
  Skipping repository untracked_some.git/

Now it displays only the file and directory names that got actually
deleted and shows the name of the untracked git repositories it ignored.

Reported-by: Soren Brinkmann <soren.brinkmann@xilinx.com>

Signed-off-by: Zoltan Klinger <zoltan.klinger@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
[SQUASH???] style fixes
Merge branch 'zk/clean-report-failure' into pu

"git clean" states what it is going to remove and then goes on to
remove it, but sometimes it only discovers things that cannot be
removed after recursing into a directory, which makes the output
confusing and even wrong.

Expecting a response to $gmane/212860.

* zk/clean-report-failure:
  [SQUASH???] style fixes
  git-clean: Display more accurate delete messages
Merge branch 'rt/commit-cleanup-config' into pu

Add a configuration variable to set default clean-up mode other
than "strip".

* rt/commit-cleanup-config:
  commit: make default of "cleanup" option configurable
Merge branch 'jc/custom-comment-char' into pu

An illustration to show codepaths that need to be touched to change
the hint lines in the edited text to begin with something other
than '#'.

* jc/custom-comment-char:
  Allow custom "comment char"
Merge branch 'jn/maint-trim-vim-contrib' into pu

Will merge to 'next'.

* jn/maint-trim-vim-contrib:
  contrib/vim: simplify instructions for old vim support
### Expecting a reroll
Merge branch 'mb/remote-default-nn-origin' into pu

When the user does not specify what remote to interact with, we
often attempt to use 'origin'.  This can now be customized via a
configuration variable.

Expecting a reroll.
$gmane/210151

"The first remote becomes the default" bit is better done as a
separate step.

* mb/remote-default-nn-origin:
  Teach get_default_remote to respect remote.default.
  Test that plain "git fetch" uses remote.default when on a detached HEAD.
  Teach clone to set remote.default.
  Teach "git remote" about remote.default.
  Teach remote.c about the remote.default configuration setting.
  Rename remote.c's default_remote_name static variables.

Conflicts:
	builtin/remote.c
	t/t5505-remote.sh
Merge branch 'mb/gitweb-highlight-link-target' into pu

Expecting a reroll.
$gmane/211935

* mb/gitweb-highlight-link-target:
  Highlight the link target line in Gitweb using CSS
Merge branch 'bc/append-signed-off-by' into pu

Expecting a reroll.
$gmane/212507

* bc/append-signed-off-by:
  t4014: do not use echo -n
  Unify appending signoff in format-patch, commit and sequencer
  format-patch: update append_signoff prototype
  format-patch: stricter S-o-b detection
  t4014: more tests about appending s-o-b lines
  sequencer.c: teach append_signoff to avoid adding a duplicate newline
  sequencer.c: teach append_signoff how to detect duplicate s-o-b
  sequencer.c: always separate "(cherry picked from" from commit body
  sequencer.c: recognize "(cherry picked from ..." as part of s-o-b footer
  t/t3511: add some tests of 'cherry-pick -s' functionality
  t/test-lib-functions.sh: allow to specify the tag name to test_commit
  sequencer.c: remove broken support for rfc2822 continuation in footer

Conflicts:
	builtin/log.c
	t/t4014-format-patch.sh
Merge branch 'nd/clone-no-separate-git-dir-with-bare' into pu

Expecting a reroll.
$gmane/212863

* nd/clone-no-separate-git-dir-with-bare:
  clone: forbid --bare --separate-git-dir <dir>
Merge branch 'mp/complete-paths' into pu

The completion script used to let the default completer to suggest
pathnames, which gave too many irrelevant choices (e.g. "git add"
would not want to add an unmodified path).  Teach it to use a more
git-aware logic to enumerate only relevant ones.

It has been reported (no surprise) that this does not work inside
subdirectory, and fixing it seems to be non-trivial. $gmane/212642

Waiting for area-experts' help.

* mp/complete-paths:
  git-completion.bash: add support for path completion

Conflicts:
	contrib/completion/git-completion.bash
### Stalled
Merge branch 'jc/xprm-generation' into pu

A toy to analyze how bad the clock skews are in histories of real
world projects.

Stalled mostly due to lack of responses.

* jc/xprm-generation:
  test-generation: compute generation numbers and clock skews
Merge branch 'jc/maint-name-rev' into pu

"git name-rev" names the given revision based on a ref that can be
reached in the smallest number of steps from the rev, but that is
not useful when the caller wants to know which tag is the oldest one
that contains the rev.  This teaches a new mode to the command that
uses the oldest ref among those which contain the rev.

I am not sure if this is worth it; for one thing, even with the help
from notes-cache, it seems to make the "describe --contains" even
slower. Also the command will be unusably slow for a user who does
not have a write access (hence unable to create or update the
notes-cache).

Stalled mostly due to lack of responses.

* jc/maint-name-rev:
  describe --contains: use "name-rev --algorithm=weight"
  name-rev --algorithm=weight: tests and documentation
  name-rev --algorithm=weight: cache the computed weight in notes
  name-rev --algorithm=weight: trivial optimization
  name-rev: --algorithm option
  name_rev: clarify the logic to assign a new tip-name to a commit
  name-rev: lose unnecessary typedef

Conflicts:
	builtin/name-rev.c
Merge branch 'jk/lua-hackery' into pu

Interesting exercise. When we do this for real, we probably would want
to wrap a commit to make it more like an "object" with methods like
"parents", etc.

* jk/lua-hackery:
  pretty: fix up one-off format_commit_message calls
  Minimum compilation fixup
  Makefile: make "lua" a bit more configurable
  add a "lua" pretty format
  add basic lua infrastructure
  pretty: make some commit-parsing helpers more public
Merge branch 'rc/maint-complete-git-p4' into pu

Comment from Pete will need to be addressed ($gmane/206172).

* rc/maint-complete-git-p4:
  Teach git-completion about git p4
Merge branch 'jl/submodule-deinit' into pu

There was no Porcelain way to say "I no longer am interested in
this submodule", once you express your interest in a submodule with
"submodule init".  "submodule deinit" is the way to do so.

Expecting a reroll.
$gmane/212884

* jl/submodule-deinit:
  submodule: add 'deinit' command

Conflicts:
	Documentation/git-submodule.txt
	git-submodule.sh
Merge branch 'jc/add-delete-default' into pu

"git add dir/" updated modified files and added new files, but does
not notice removed files, which may be "Huh?" to some users.  They
can of course use "git add -A dir/", but why should they?

Resurrected from graveyard, as I thought it was a worthwhile thing
to do in the longer term.

Stalled mostly due to lack of responses.

* jc/add-delete-default:
  git add: notice removal of tracked paths by default
### Conflicting