submodule.<name>.update can be assigned an arbitrary command via setting
it to "!command". When this command is found in the regular config, Git
ought to just run that command instead of other update mechanisms.

However if that command is just found in the .gitmodules file, it is
potentially untrusted, which is why we do not run it.  Add a test
confirming the behavior.
Suggested-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The GETTEXT_POISON=YesPlease compile-time testing option added in my
bb946bba ("i18n: add GETTEXT_POISON to simulate unfriendly
translator", 2011-02-22) has been slowly bitrotting as strings have
been marked for translation, and new tests have been added without
running it.

I brought this up on the list ("[BUG] test suite broken with
GETTEXT_POISON=YesPlease", [1]) asking whether this mode was useful at
all anymore. At least one person occasionally uses it, and Lars
Schneider offered to change one of the the Travis builds to run in
this mode, so fix up the failing ones.

My test setup runs most of the tests, with the notable exception of
skipping all the p4 tests, so it's possible that there's still some
lurking regressions I haven't fixed.

1. <CACBZZX62+acvi1dpkknadTL827mtCm_QesGSZ=6+UnyeMpg8+Q@mail.gmail.com>
Signed-off-by: NÆvar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

There are three issues with the test:

* The syntax of the here-doc was wrong, such that the entire test was
  sucked into the here-doc, which is why the test succeeded.

* The variable $submodulesha1 was not expanded as it was inside a quoted
  here text.  We do not want to quote EOF marker for this.

* The redirection from the git command to the output file for comparison
  was wrong as the -C operator from git doesn't apply to the redirect path.
  Also we're interested in stderr of that command.
Noticed-by: NJan Palus <jan.palus@gmail.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In 1b4735d9 (submodule: no [--merge|--rebase] when newly cloned,
2011-02-17), all actions were defaulted to checkout for populating
a submodule initially, because merging or rebasing makes no sense
in that situation.

Other commands however do make sense, such as the custom command
that was added later (6cb5728c, submodule update: allow custom
command to update submodule working tree, 2013-07-03).

I am unsure about the "none" command, as I can see an initial
checkout there as a useful thing. On the other hand going strictly
by our own documentation, we should do nothing in case of "none"
as well, because the user asked for it.
Reported-by: NHan-Wen Nienhuys <hanwen@google.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In the submodule helper we did not correctly handled the display path
for initializing submodules when both the submodule is inside a
subdirectory as well as the command being invoked from a subdirectory
(as viewed from the superproject).

This was broken in 3604242f, which was written at a time where
there was no super-prefix available, so we abused the --prefix option
for the same purpose and could get only one case right (the call from
within a subdirectory, not the submodule being in a subdirectory).
Test-provided-by: NDavid Turner <novalis@novalis.org>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

On OSX `wc` prefixes the output of numbers with whitespace, such
that the `commit_count` would be "SP <NUMBER>". When using that in

    git submodule update --init --depth=$commit_count

the depth would be empty and the number is interpreted as the
pathspec.  Fix this by not using `wc` and rather instruct rev-list
to count.

Another way to fix this is to remove the `=` sign after the
`--depth` argument as then we are allowed to have more than just one
whitespace between `--depth` and the actual number.  Prefer the
solution of rev-list counting as that is expected to be slightly
faster and more self-contained within Git.
Reported-by: NLars Schneider <larsxschneider@gmail.com>
Helped-by: Junio C Hamano <gitster@pobox.com>,
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Gerrit has a "superproject subscription" feature[1], that triggers a
commit in a superproject that is subscribed to its submodules.
Conceptually this Gerrit feature can be done on the client side with
Git via (except for raciness, error handling etc):

  while [ true ]; do
    git -C <superproject> submodule update --remote --force
    git -C <superproject> commit -a -m "Update submodules"
    git -C <superproject> push
  done

for each branch in the superproject. To ease the configuration in Gerrit
a special value of "." has been introduced for the submodule.<name>.branch
to mean the same branch as the superproject[2], such that you can create a
new branch on both superproject and the submodule and this feature
continues to work on that new branch.

Now we find projects in the wild with such a .gitmodules file.
The .gitmodules used in these Gerrit projects do not conform
to Gits understanding of how .gitmodules should look like.
This teaches Git to deal gracefully with this syntax as well.

The redefinition of "." does no harm to existing projects unaware of
this change, as "." is an invalid branch name in Git, so we do not
expect such projects to exist.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When depth is given the user may have a reasonable expectation that
any remote operation is using the given depth. Add a test to demonstrate
we still get the desired sha1 even if the depth is too short to
include the actual commit.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The prior hard coded depth was chosen to be exactly the length from the
recorded gitlink to the tip of the remote, so if you add more commits
to the remote before, this test will not test its intention any more.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The test functions test_i18ncmp and test_i18ngrep pretend success if run
under GETTEXT_POISON. By using those functions to test output which is
correctly marked as translatable, enables one to detect if the strings
newly marked for translation are from plumbing output. If they are
indeed from plumbing, the test would fail, and the string should be
unmarked, since it is not seen by users.

Thus, it is productive to not have false positives when running the test
under GETTEXT_POISON. This commit replaces normal test functions by
their i18n aware variants in use-cases know to be correctly marked for
translation, suppressing false positives.
Signed-off-by: NVasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Reroute the output of stdout to stderr as it is just informative
messages, not to be consumed by machines.

This should not regress any scripts that try to parse the
current output, as the output is already internationalized
and therefore unstable.

We want to init submodules from the helper for `submodule update`
in a later patch and the stdout output of said helper is consumed
by the parts of `submodule update` which are still written in shell.
So we have to be careful which messages are on stdout.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This patch is just a test and fixes no bug as there is currently no bug
in the path handling of `submodule update`.

In `submodule update` we make a call to `submodule--helper list --prefix
"$wt_prefix"` which looks a bit brittle and likely to introduce a bug
for the path handling. It is not a bug as the prefix is ignored inside
the submodule helper for now. If this test breaks eventually, we want
to make sure the `wt_prefix` is passed correctly into recursive submodules.
Hint: In recursive submodules we expect `wt_prefix` to be empty.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In the predefined actions (merge, rebase, none, checkout), we use
the display path, which is relative to the current working directory.
Also use the display path when running a custom command.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When calling `git submodule init` from a recursive instance of
`git submodule update --recursive`, the reported path is wrong as it
skips the nested submodules.

The new test demonstrates a failure in the code prior to this patch.
Instead of getting the expected
    Submodule 'submodule' (${pwd}/submodule) registered for path '../super/submodule'
the `super` directory is omitted and you get
    Submodule 'submodule' (${pwd}/submodule) registered for path '../submodule'
instead.
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Just pass it along to "git submodule update", which may pick reasonable
defaults if you don't specify an explicit number.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Expose possible parallelism either via the "--jobs" CLI parameter or
the "submodule.fetchJobs" setting.

By having the variable initialized to -1, we make sure 0 can be passed
into the parallel processing machine, which will then pick as many parallel
workers as there are CPUs.
Reviewed-by: NJonathan Nieder <jrnieder@gmail.com>
Signed-off-by: NStefan Beller <sbeller@google.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The Git CodingGuidelines prefer the $(...) construct for command
substitution instead of using the backquotes `...`.

The backquoted form is the traditional method for command
substitution, and is supported by POSIX.  However, all but the
simplest uses become complicated quickly.  In particular, embedded
command substitutions and/or the use of double quotes require
careful escaping with the backslash character.

The patch was generated by:

for _f in $(find . -name "*.sh")
do
	perl -i -pe 'BEGIN{undef $/;} s/`(.+?)`/\$(\1)/smg'  "${_f}"
done

and then carefully proof-read.
Signed-off-by: NElia Pinto <gitter.spiros@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

These are tests which are missing a link in their &&-chain,
but during a setup phase. We may fail to notice failure in
commands that build the test environment, but these are
typically not expected to fail at all (but it's still good
to double-check that our test environment is what we
expect).
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This reverts commit 23d25e48, as it is
broken for users who haven't opted into the new feature of checking
out submodule.*.branch with update mode set to checkout.

The previous code only checked out branches in cmd_add.  This commit
moves the branch-checkout logic into module_clone, where it can be
shared by cmd_add and cmd_update.  I also update the initial checkout
command to use 'reset' to preserve branches setup during module_clone.

With this change, folks cloning submodules for the first time via:

  $ git submodule update ...

will get a local branch instead of a detached HEAD, unless they are
using the default checkout-mode updates.  This is a change from the
previous situation where cmd_update always used checkout-mode logic
(regardless of the requested update mode) for updates that triggered
an initial clone, which always resulted in a detached HEAD.

This commit does not change the logic for updates after the initial
clone, which will continue to create detached HEADs for checkout-mode
updates, and integrate remote work with the local HEAD (detached or
not) in other modes.

The motivation for the change is that developers doing local work
inside the submodule are likely to select a non-checkout-mode for
updates so their local work is integrated with upstream work.
Developers who are not doing local submodule work stick with
checkout-mode updates so any apparently local work is blown away
during updates.  For example, if upstream rolls back the remote branch
or gitlinked commit to an earlier version, the checkout-mode developer
wants their old submodule checkout to be rolled back as well, instead
of getting a no-op merge/rebase with the rolled-back reference.

By using the update mode to distinguish submodule developers from
black-box submodule consumers, we can setup local branches for the
developers who will want local branches, and stick with detached HEADs
for the developers that don't care.

Testing
=======

In t7406, just-cloned checkouts now update to the gitlinked hash with
'reset', to preserve the local branch for situations where we're not
on a detached HEAD.

I also added explicit tests to t7406 for HEAD attachement after
cloning updates, showing that it depends on their update mode:

* Checkout-mode updates get detached HEADs
* Everyone else gets a local branch, matching the configured
  submodule.<name>.branch and defaulting to master.

The 'initial-setup' tag makes it easy to reset the superproject to a
known state, as several earlier tests commit to submodules and commit
the changed gitlinks to the superproject, but don't push the new
submodule commits to the upstream subprojects.  This makes it
impossible to checkout the current super master, because it references
submodule commits that don't exist in the upstream subprojects.  For a
specific example, see the tests that currently generate the
'two_new_submodule_commits' commits.

Documentation
=============

I updated the docs to describe the 'submodule update' modes in detail.
The old documentation did not distinguish between cloning and
non-cloning updates and lacked clarity on which operations would lead
to detached HEADs, and which would not.  The new documentation
addresses these issues while updating the docs to reflect the changes
introduced by this commit's explicit local branch creation in
module_clone.

I also add '--checkout' to the usage summary and group the update-mode
options into a single set.
Signed-off-by: NW. Trevor King <wking@tremily.us>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When submodule.$name.update is given as hint from the upstream in
the .gitmodules file, we used to blindly copy it to .git/config,
unless there already is a value defined for the submodule.

However, there is no reason to expect that the update mode hinted by
the upstream is available in the version of Git the user is using,
and a really custom "!cmd" prepared by an upstream person running on
Linux may not even be available to a user on Windows.  It is simply
irresponsible to copy the setting blindly and to attempt to use it
during a later "submodule update" without validating it first.

Just show the suggested value to the diagnostic output, and set the
value to 'none' in the configuration, if it is not one of the ones
that are known to be supported by this version of Git.
Helped-by: NJens Lehmann <Jens.Lehmann@web.de>
Helped-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

cmd_update() in the submodule script tries to preserve the options given
on the command line in the "orig_flags" variable to pass them on into the
recursion when the '--recursive' option is given. But this isn't necessary
because all the variables set by the options will be seen in the recursion
too as that is achieved by executing "eval cmd_update".

The same has already been done for cmd_status() in e15bec0e, so let's
clean up cmd_update() likewise. Also add a test to make sure that a
submodule name given on the command line is not passed into the recursion
(which was the goal of adding the orig_flags variable in 98dbe63d).
Signed-off-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

322bb6e1 (2011 Aug 11) introduced a new subshell at the end of a test
case but omitted a '&&' to join the two; fix this.
Signed-off-by: NTay Ray Chuan <rctay89@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Add the --depth option to the add and update commands of "git submodule",
which is then passed on to the clone command. This is useful when the
submodule(s) are huge and you're not really interested in anything but
the latest commit.

Tests are added and some indention adjustments were made to conform to the
rest of the testfile on "submodule update can handle symbolic links in pwd".
Signed-off-by: NFredrik Gustafsson <iveqy@iveqy.com>
Acked-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Users can set submodule.$name.update to '!command' which will cause
'command' to be run instead of checkout/merge/rebase. This allows
the user finer-grained control over how the update is done.

The primary motivation for this was interoperability with stgit;
however being able to intercept the submodule update process may
prove useful for integrating with or extending other tools.
Signed-off-by: NChris Packham <judge.packham@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Use the new rev-parse --prefix option to process all paths given to the
submodule command, dropping the requirement that it be run from the
top-level of the repository.

Since the interpretation of a relative submodule URL depends on whether
or not "remote.origin.url" is configured, explicitly block relative URLs
in "git submodule add" when not at the top level of the working tree.
Signed-off-by: NJohn Keeping <john@keeping.me.uk>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When a remote ref or a tag is checked out, HEAD is automatically
detached. There is no user-friendly way to find out what ref is
checked out in this case. This patch digs in reflog for this
information and shows "HEAD detached from origin/master" or "HEAD
detached at v1.8.0" instead of "currently not on any branch".

When it cannot figure out the original ref, it shows an abbreviated
SHA-1. "Currently not on any branch" would never display (unless
reflog is pruned to near empty that the last checkout entry is lost).
Signed-off-by: NNguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Previously when using update with recursion, only the path for the
inner-most module was printed. Now the path is printed relative to
the directory the command was started from. This now matches the
behavior of submodule foreach.
Signed-off-by: NWilliam Entriken <github.com@phor.net>
Acked-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The current `update` command incorporates the superproject's gitlinked
SHA-1 ($sha1) into the submodule HEAD ($subsha1).  Depending on the
options you use, it may checkout $sha1, rebase the $subsha1 onto
$sha1, or merge $sha1 into $subsha1.  This helps you keep up with
changes in the upstream superproject.

However, it's also useful to stay up to date with changes in the
upstream subproject.  Previous workflows for incorporating such
changes include the ungainly:

  $ git submodule foreach 'git checkout $(git config --file $toplevel/.gitmodules submodule.$name.branch) && git pull'

With this patch, all of the useful functionality for incorporating
superproject changes can be reused to incorporate upstream subproject
updates.  When you specify --remote, the target $sha1 is replaced with
a $sha1 of the submodule's origin/master tracking branch.  If you want
to merge a different tracking branch, you can configure the
`submodule.<name>.branch` option in `.gitmodules`.  You can override
the `.gitmodules` configuration setting for a particular superproject
by configuring the option in that superproject's default configuration
(using the usual configuration hierarchy, e.g. `.git/config`,
`~/.gitconfig`, etc.).

Previous use of submodule.<name>.branch
=======================================

Because we're adding a new configuration option, it's a good idea to
check if anyone else is already using the option.  The foreach-pull
example above was described by Ævar in

  commit f030c96d
  Author: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
  Date:   Fri May 21 16:10:10 2010 +0000

    git-submodule foreach: Add $toplevel variable

Gerrit uses the same interpretation for the setting, but because
Gerrit has direct access to the subproject repositories, it updates
the superproject repositories automatically when a subproject changes.
Gerrit also accepts the special value '.', which it expands into the
superproject's branch name.

Although the --remote functionality is using `submodule.<name>.branch`
slightly differently, the effect is the same.  The foreach-pull
example uses the option to record the name of the local branch to
checkout before pulls.  The tracking branch to be pulled is recorded
in `.git/modules/<name>/config`, which was initialized by the module
clone during `submodule add` or `submodule init`.  Because the branch
name stored in `submodule.<name>.branch` was likely the same as the
branch name used during the initial `submodule add`, the same branch
will be pulled in each workflow.

Implementation details
======================

In order to ensure a current tracking branch state, `update --remote`
fetches the submodule's remote repository before calculating the
SHA-1.  However, I didn't change the logic guarding the existing fetch:

  if test -z "$nofetch"
  then
    # Run fetch only if $sha1 isn't present or it
    # is not reachable from a ref.
    (clear_local_git_env; cd "$path" &&
      ( (rev=$(git rev-list -n 1 $sha1 --not --all 2>/dev/null) &&
       test -z "$rev") || git-fetch)) ||
    die "$(eval_gettext "Unable to fetch in submodule path '\$path'")"
  fi

There will not be a double-fetch, because the new $sha1 determined
after the `--remote` triggered fetch should always exist in the
repository.  If it doesn't, it's because some racy process removed it
from the submodule's repository and we *should* be re-fetching.
Signed-off-by: NW. Trevor King <wking@tremily.us>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

When adding a new submodule it can happen that .git/modules/<name> already
contains a submodule repo, e.g. when a submodule is removed from the work
tree and another submodule is added at the same path. But then the work
tree of the submodule will be populated using the existing repository and
not the one the user provided, which results in an incorrect work tree. On
the other hand the user might reactivate a submodule removed earlier, then
reusing that .git directory is the Right Thing to do.

As git can't decide what is the case, error out and tell the user she
should use either use a different name for the submodule with the "--name"
option or can reuse the .git directory for the newly added submodule by
providing the --force option (which only makes sense when the upstream
matches, so the error message lists all remotes of .git/modules/<name>).

In one test in t7406 the --force option had to be added to "git submodule
add", as that test re-adds a formerly removed submodule.
Reported-by: NJonathan Johnson <me@jondavidjohn.com>
Signed-off-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Currently, it will only do a checkout if the sha1 registered in the containing
repository doesn't match the HEAD of the submodule, regardless of whether the
submodule is dirty.  As discussed on the mailing list, the '--force' flag is a
strong indicator that the state of the submodule is suspect, and should be reset
to HEAD.
Signed-off-by: NStefan Zager <szager@google.com>
Acked-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

The test happened to use "rev-parse --max-count=1 HEAD" consistently
to prepare the expected output and the actual output, so the
comparison between them gave us a correct success/failure because
both output had irrelevant "--max-count=1" in it.

But that is not an excuse to keep it broken.  Replace it a more
meaningful construct "rev-parse --verify HEAD".

Noticed by Daniel Graña while working on his submodule tests.
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since 69c30517 (submodules: refactor computation of relative gitdir path)
cloning a submodule recursively fails for nested submodules when a
symbolic link is part of the path to the work tree of the superproject.

This happens when module_clone() tries to find the relative paths between
the work tree and the git dir. When a symbolic link in current $PWD points
to a directory that is at a different level, then determining the number
of "../" needed to traverse to the superproject's work tree leads to a
wrong result.

As there is no portable way to say "pwd -P", use cd_to_toplevel to remove
the link from $PWD, which fixes this problem.

A test for this issue has been added to t7406.
Reported-by: NBob Halley <halley@play-bow.org>
Signed-off-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

In module_clone() the rel_gitdir variable was computed differently when
"git rev-parse --git-dir" returned a relative path than when it returned
an absolute path. This is not optimal, as different code paths are used
depending on the return value of that command.

Fix that by reusing the differing path components computed for setting the
core.worktree config setting, which leaves a single code path for setting
both instead of having three and makes the code much shorter.

This also fixes the bug that in the computation of how many directories
have to be traversed up to hit the root directory of the submodule the
name of the submodule was used where the path should have been used. This
lead to problems after renaming submodules into another directory level.

Even though the "(cd $somewhere && pwd)" approach breaks the flexibility
of symlinks, that is no issue here as we have to have one relative path
pointing from the work tree to the gitdir and another pointing back, which
will never work anyway when a symlink along one of those paths is changed
because the directory it points to was moved.

Also add a test moving a submodule into a deeper directory to catch any
future breakage here and to document what has to be done when a submodule
needs to be moved until git mv learns to do that. Simply moving it to the
new location doesn't work, as the core.worktree and possibly the gitfile
setting too will be wrong. So it has to be removed from filesystem and
index, then the new location has to be added into the index and the
.gitmodules file has to be updated. After that a git submodule update will
check out the submodule at the new location.
Signed-off-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Since recently a submodule with name <name> has its git directory in the
.git/modules/<name> directory of the superproject while the work tree
contains a gitfile pointing there.

When the same submodule is added on a branch where it wasn't present so
far (it is not found in the .gitmodules file), the name is not initialized
from the path as it should. This leads to a wrong path entered in the
gitfile when the .git/modules/<name> directory is found, as this happily
uses the - now empty - name. It then always points only a single directory
up, even if we have a path deeper in the directory hierarchy.

Fix that by initializing the name of the submodule early in module_clone()
if module_name() returned an empty name and add a test to catch that bug.
Reported-by: NJehan Bing <jehan@orb.com>
Signed-off-by: NJens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Move git-dir for submodules into $GIT_DIR/modules/[name_of_submodule] of
the superproject. This is a step towards being able to delete submodule
directories without loosing the information from their .git directory
as that is now stored outside the submodules work tree.

This is done relying on the already existent .git-file functionality.
When adding or updating a submodule whose git directory is found under
$GIT_DIR/modules/[name_of_submodule], don't clone it again but simply
point the .git-file to it and remove the now stale index file from it.
The index will be recreated by the following checkout.

This patch will not affect already cloned submodules at all.

Tests that rely on .git being a directory have been fixed.
Signed-off-by: NFredrik Gustafsson <iveqy@iveqy.com>
Mentored-by: NJens Lehmann <Jens.Lehmann@web.de>
Mentored-by: NHeiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

This is useful to mark a submodule as unneeded by default. When this
option is set and the user wants to work with such a submodule he
needs to configure 'submodule.<name>.update=checkout' or pass the
--checkout option. Then the submodule can be handled like a normal
submodule.
Signed-off-by: NHeiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

"git submodule update" stops at the first error and gives control
back to the user. Only after the user fixes the problematic
submodule and runs "git submodule update" again, the second error
is found. And the user needs to repeat until all the problems are
found and fixed one by one. This is tedious.

Instead, the command can remember which submodules it had trouble with,
continue updating the ones it can, and report which ones had errors at
the end. The user can run "git submodule update", find all the ones that
need minor fixing (e.g. working tree was dirty) to fix them in a single
pass. Then another "git submodule update" can be run to update all.

Note that the problematic submodules are skipped only when they are to
be integrated with a safer value of submodule.<name>.update option,
namely "checkout". Fixing a failure in a submodule that uses "rebase" or
"merge" may need an involved conflict resolution by the user, and
leaving too many submodules in states that need resolution would not
reduce the mental burden on the user.
Signed-off-by: NFredrik Gustafsson <iveqy@iveqy.com>
Mentored-by: NJens Lehmann <Jens.Lehmann@web.de>
Mentored-by: NHeiko Voigt <hvoigt@hvoigt.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

Gettextize $update_module say and die messages. These messages needed
to be split up to make them translatable.
Signed-off-by: NÆvar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>