[RFC] t7410: 210 tests for various 'git submodule update' scenarios

> +#  - current state of submodule:
> +#     ?.?.?.1 - not yet cloned
> +#     ?.?.?.2 - cloned, detached, HEAD == gitlink
> +#     ?.?.?.3 - cloned, detached, HEAD != gitlink
> +#     ?.?.?.4 - cloned, on branch foo (exists upstream), HEAD == gitlink
> +#     ?.?.?.5 - cloned, on branch foo (exists upstream), HEAD != gitlink
> +#     ?.?.?.6 - cloned, on branch bar (MISSING upstream), HEAD == gitlink
> +#     ?.?.?.7 - cloned, on branch bar (MISSING upstream), HEAD != gitlink

> +# D4: When 'submodule update' performs a clone to populate a submodule, it
> +#     currently also creates a default branch (named after origin/HEAD) in
> +#     that submodule, EVEN WHEN THAT BRANCH WILL NEVER BE USED (e.g. because
> +#     we're in checkout-mode and submodule will always be detached). Is this
> +#     good, or should the clone performed by 'submodule update' skip the
> +#     automatic local branch creation?
> +#     Affects: 1.2.*.1, 1.3.*.1, 1.4.*.1, 1.5.*.1,
> +#              2.2.*.1, 2.3.*.1, 2.4.*.1, 2.5.*.1,
> +#              3.2.1.1, 3.3.1.1, 3.4.1.1, 3.5.1.1

> +# D5: When in merge/rebase-mode, and 'submodule update' actually ends up doing
> +#     a merge/rebase, that will happen on the current branch (or detached HEAD)
> +#     and NOT on the configured (or default) .branch. Is this OK? Should we
> +#     abort (or at least warn) instead? (In general, .branch seems only to
> +#     affect the submodule's HEAD when the submodule is first cloned.)
> +#     (This discussion point is related to D3 and D6)
> +#     Affects: 1.3.1.3, 1.3.1.5, 1.3.1.7, 1.3.2.>=2,
> +#              1.4.1.3, 1.4.1.5, 1.4.1.7, 1.4.2.>=2,
> +#              2.3.1.3, 2.3.1.5, 2.3.1.7, 2.3.2.2, 2.3.2.4, 2.3.2.6,
> +#              2.4.1.3, 2.4.1.5, 2.4.1.7, 2.4.2.2, 2.4.2.4, 2.4.2.6
> +#              3.3.1.3, 3.3.1.5, 3.3.1.7
> +#              3.4.1.3, 3.4.1.5, 3.4.1.7

> …                               This is probably the more useful setting, and it
> +#     becomes obviously correct after (re-)reading gitmodules(5) and
> +#     git-config(1). However, from just reading the "update" section in
> +#     git-submodule(1) (or not even that), things are not so clear-cut. Would
> +#     submodule.<name>.upstream (or .remote-branch, or similar) be a better
> +#     name for this?

> +# D7: What to do when .branch refers to a branch that is missing from upstream?
> +#     Currently, when trying to clone, the clone fails (which causes 'git
> +#     submodule update --remote' to fail), but leaves the submodule in an
> +#     uninitialized state (there is a .git, but the work tree is missing).
> +#     This is probably not the behavior we want...
> +#     Affects: pre, 3.2.2.1, 3.3.2.1, 3.4.2.1, 3.5.2.1

> On Wed, Apr 16, 2014 at 02:54:48AM +0200, Johan Herland wrote:
>> This is a work-in-progress to flesh out (and promote discussion about)
>> the expected behaviors for all possible scenarios in which
>> 'git submodule update' might be run.
>
> This is lovely :).

>> +#  - current state of submodule:
>> +#     ?.?.?.1 - not yet cloned
>> +#     ?.?.?.2 - cloned, detached, HEAD == gitlink
>> +#     ?.?.?.3 - cloned, detached, HEAD != gitlink
>> +#     ?.?.?.4 - cloned, on branch foo (exists upstream), HEAD == gitlink
>> +#     ?.?.?.5 - cloned, on branch foo (exists upstream), HEAD != gitlink
>> +#     ?.?.?.6 - cloned, on branch bar (MISSING upstream), HEAD == gitlink
>> +#     ?.?.?.7 - cloned, on branch bar (MISSING upstream), HEAD != gitlink
>
> The remote branches should only matter for the initial clone and
> --remote updates.  Also, only the configured submodule.<name>.branch
> (your first axis) should be checked; the locally checked-out submodule
> branch shouldn't matter.

>> +# T2: Test with submodule.<name>.url != submodule's remote.origin.url. Does
>> +#     "submodule update --remote" sync with submodule.<name>.url, or with the
>> +#     submodule's origin? (or with the submodule's current branch's upstream)?
>
> All fetches should currently use the submodule's remote.origin.url.
> submodule.<name>.url is only used for the initial clone (*.*.*.1), and
> never referenced again.  This would change using my tightly-bound
> submodule proposal [1], where a difference between
> submodule.<name>.url and the submodule's @{upstream} URL would be
> trigger a dirty-tree condition (for folks with tight-bind syncing
> enabled) from which you couldn't update before resolving the
> difference.

>> +# D1: When submodule is already at right commit, checkout-mode currently does
>> +#     nothing. Should it instead detach, even when no update is needed?
>> +#     Affects: 1.2.1.4, 1.2.1.6, 2.2.1.4, 2.2.1.6, 3.2.1.4, 3.2.1.6
>
> “Checkout updates always leave a detached HEAD” seems easier to
> explain, so I'm leaning that way.

>> +# D2: Should all/some of 1.3.*/1.4.* abort/error because we don't know what to
>> +#     merge/rebase with (because .branch is unset)? Or is the current default
>> +#     to origin/HEAD OK?
>> +#     Affects: 1.3.*, 1.4.*
>
> Maybe you mean 1.3.*, 1.4.*, and 1.5.* (merge, rebase, and !command)?
> In all of these cases, we're integrating the current HEAD with the
> gitlinked (*.*.1.*) or remote-tracking branch (*.*.2.*).  Since
> submodule.<name>.branch defaults to master (and may be changed to HEAD
> after a long transition period? [2,3]), I don't think we should
> abort/error in those cases.

>> +# D3: When submodule is already at right commit, merge/rebase-mode currently
>> +#     does nothing. Should it do something else (e.g. not leave submodule
>> +#     detached, or checked out on the "wrong" branch (i.e. != .branch))?
>> +#     (This discussion point is related to D1, D5 and D6)
>
> “Non-checkout updates always leave you on a branch” seems easier to
> explain, but I think we'd want to distinguish between the local branch
> and the remote submodule.<name>.branch [1].  Lacking that distinction,
> I'd prefer to leave the checked-out branch unchanged.

>> +# D4: When 'submodule update' performs a clone to populate a submodule, it
>> +#     currently also creates a default branch (named after origin/HEAD) in
>> +#     that submodule, EVEN WHEN THAT BRANCH WILL NEVER BE USED (e.g. because
>> +#     we're in checkout-mode and submodule will always be detached). Is this
>> +#     good, or should the clone performed by 'submodule update' skip the
>> +#     automatic local branch creation?
>> +#     Affects: 1.2.*.1, 1.3.*.1, 1.4.*.1, 1.5.*.1,
>> +#              2.2.*.1, 2.3.*.1, 2.4.*.1, 2.5.*.1,
>> +#              3.2.1.1, 3.3.1.1, 3.4.1.1, 3.5.1.1
>
> “Checkout updates always leave a detached HEAD” seems easier to
> explain, so I'm leaning that way.

>> +# D5: When in merge/rebase-mode, and 'submodule update' actually ends up doing
>> +#     a merge/rebase, that will happen on the current branch (or detached HEAD)
>> +#     and NOT on the configured (or default) .branch. Is this OK? Should we
>> +#     abort (or at least warn) instead? (In general, .branch seems only to
>> +#     affect the submodule's HEAD when the submodule is first cloned.)
>> +#     (This discussion point is related to D3 and D6)
>> +#     Affects: 1.3.1.3, 1.3.1.5, 1.3.1.7, 1.3.2.>=2,
>> +#              1.4.1.3, 1.4.1.5, 1.4.1.7, 1.4.2.>=2,
>> +#              2.3.1.3, 2.3.1.5, 2.3.1.7, 2.3.2.2, 2.3.2.4, 2.3.2.6,
>> +#              2.4.1.3, 2.4.1.5, 2.4.1.7, 2.4.2.2, 2.4.2.4, 2.4.2.6
>> +#              3.3.1.3, 3.3.1.5, 3.3.1.7
>> +#              3.4.1.3, 3.4.1.5, 3.4.1.7
>
> With the --remote option that added submodule.<name>.branch (which
> eventually landed with v8 of that series [4]), I initially imagined it
> as the name of the local branch [5], but transitioned to imagining it
> as the name of the remote-tracking branch in v5 of that series [6].
> There were no major logical changes between v5 and v8.  With the v8
> version that landed in Git v1.8.2, submodule.<name>.branch was clearly
> the name of the remote-tracking branch, and we gave no way to
> separately configure the local branch.

> Recently, we decided that local branches might be important after all
> [7], which lead to the partially landed v5 of my local-branch-creation
> series [8], now partially reverted with d851ffb (Revert "submodule:
> explicit local branch creation in module_clone", 2014-04-02).  Like v4
> of that series [9], I considered the landed-and-now-reverted v5 to be
> a stop-gap until we got better local-branch handling.
>
> Anyhow, that's why submodule.<name>.branch is only important when we
> interact with the remote repository (during clones and --remote
> updates).  We've never landed a patch that explicitly addresses what
> the local branch should be.

>> +# D6: The meaning of submodule.<name>.branch is initially confusing, as it does
>> +#     not really concern the submodule's local branch (except as a naming hint
>> +#     when the submodule is first cloned). Instead, submodule.<name>.branch is
>> +#     really about which branch in the _upstream_ submodule
>
> Which is how gitmodules(5) explains it:
>
>   submodule.<name>.branch
>     A remote branch name for tracking updates…

>> +#     submodule.<name>.url, or by the submodule's remote.origin.url?)
>> +#     want to integrate with.
>
> The submodule's remote.origin.url for everything except the initial
> clone (*.*.*.1).  See my response to T2.

>> …                               This is probably the more useful setting, and it
>> +#     becomes obviously correct after (re-)reading gitmodules(5) and
>> +#     git-config(1). However, from just reading the "update" section in
>> +#     git-submodule(1) (or not even that), things are not so clear-cut. Would
>> +#     submodule.<name>.upstream (or .remote-branch, or similar) be a better
>> +#     name for this?
>
> Are the docs from 23d25e4 (submodule: explicit local branch creation
> in module_clone, 2014-01-26; now reverted with d851ffb, Revert
> "submodule: explicit local branch creation in module_clone",
> 2014-04-02) clearer?  Maybe we can salvage some of those docs even
> though we've reverted the actual code changes?

>> +# D7: What to do when .branch refers to a branch that is missing from upstream?
>> +#     Currently, when trying to clone, the clone fails (which causes 'git
>> +#     submodule update --remote' to fail), but leaves the submodule in an
>> +#     uninitialized state (there is a .git, but the work tree is missing).
>> +#     This is probably not the behavior we want...
>> +#     Affects: pre, 3.2.2.1, 3.3.2.1, 3.4.2.1, 3.5.2.1
>
> I think we should remove the submodule's .git file after the failed clone.

> >> +# T2: Test with submodule.<name>.url != submodule's remote.origin.url. Does
> >> +#     "submodule update --remote" sync with submodule.<name>.url, or with the
> >> +#     submodule's origin? (or with the submodule's current branch's upstream)?
> >
> > All fetches should currently use the submodule's remote.origin.url.
> > submodule.<name>.url is only used for the initial clone (*.*.*.1), and
> > never referenced again.  This would change using my tightly-bound
> > submodule proposal [1], where a difference between
> > submodule.<name>.url and the submodule's @{upstream} URL would be
> > trigger a dirty-tree condition (for folks with tight-bind syncing
> > enabled) from which you couldn't update before resolving the
> > difference.
> 
> Ok. As stated above, I am worried about the amount of duplicated
> state between the superproject's submodule config (which itself is
> split between .gitmodules and .git/config) and the submodule's own
> config. And from the above paragraph, I suspect two more dimensions
> need to be added to the test matrix:
> 
>  - submodule's remote.origin.url ==/!= submodule.<name>.url
> 
>  - "tightly-bound submodule" is enabled/disabled

> * git submodule [--quiet] add [-b <branch>] [-f|--force] [--name <name>]
>                 [--reference <repository>] [--] <repository> [<path>]
> * git submodule [--quiet] init [--] [<path>...]
> * git submodule [--quiet] deinit [-f|--force] [--] <path>...
> * git submodule [--quiet] foreach [--recursive] <command>

>  - submodule.<name>.update: …
>     …
>     - 'git reset --hard $GITLINK'
>       Equivalent to checkout-mode (without --remote).
> 
>     - 'git fetch && git reset --hard origin/HEAD'
>       Equivalent to checkout-mode with --remote.

> >> +# D6: The meaning of submodule.<name>.branch is initially confusing, as it does
> >> +#     not really concern the submodule's local branch (except as a naming hint
> >> +#     when the submodule is first cloned). Instead, submodule.<name>.branch is
> >> +#     really about which branch in the _upstream_ submodule
> >
> > Which is how gitmodules(5) explains it:
> >
> >   submodule.<name>.branch
> >     A remote branch name for tracking updates…
> 
> Good, but I fear gitmodules(5) is too hidden for the regular user.
> It'd be better to mention this in git-submodule(1), as I expect
> gitmodules(5) is largely read by .gitmodules _authors_, and not
> regular users. Obviously, the real fix would be a better name...

> >> +#     submodule.<name>.url, or by the submodule's remote.origin.url?)
> >> +#     want to integrate with.
> >
> > The submodule's remote.origin.url for everything except the initial
> > clone (*.*.*.1).  See my response to T2.
> 
> As mentioned above, submodule.<name>.url is then an unnecessary state
> duplication.

> >> +# D7: What to do when .branch refers to a branch that is missing from upstream?
> >> +#     Currently, when trying to clone, the clone fails (which causes 'git
> >> +#     submodule update --remote' to fail), but leaves the submodule in an
> >> +#     uninitialized state (there is a .git, but the work tree is missing).
> >> +#     This is probably not the behavior we want...
> >> +#     Affects: pre, 3.2.2.1, 3.3.2.1, 3.4.2.1, 3.5.2.1
> >
> > I think we should remove the submodule's .git file after the failed clone.
> 
> Agreed, but does that extend to the superproject's .git/modules/<name> too?

> More details in the top of t/t7410-submodule-update-scenarios.sh
> 
> Cc: W. Trevor King <wking@tremily.us>
> Cc: Jens Lehmann <Jens.Lehmann@web.de>
> Cc: Heiko Voigt <hvoigt@hvoigt.net>
> Cc: Junio C Hamano <gitster@pobox.com>
> 
> ---
> 
> Hi,
> 
> This started as an exercise for myself to figure out all the various
> corner cases under which "git submodule update" may be run. Then, as I
> found some cases where the current behavior was not immediately obvious
> to me, and some other cases where the current behaviour is likely buggy
> and/or Wrong(tm), I figured these tests might serve as a backdrop for a
> closer discussion of those cases.
> 
> I've attempted to include all variables/axes that combine to directly
> affect the behavior of 'submodule update'. I've excluded some variables
> whose effect on 'submodule update' is completely orthogonal/independent
> (i.e. how 'submodule update' is affected by unstaged/uncommitted
> changes in the submodule). That said, there might be more variables
> that I have missed in my analysis...
> 
> I've attempted to split the areas to be discussed into 3 todo items and
> 7 discussion items (labeled T1 - T3. and D1 - D7, respectively), and
> I've cross-referenced them to the specific test cases that are affected
> by each todo/discussion item.
> 
> I'll leave it up to Jens and Junio to determine whether this patch
> is worth applying or not. There is certainly considerable overlap
> between these tests and existing tests for 'submodule update'. There's
> also plenty of room for refactoring and deduplication in this file,
> itself, although I hope the current format of the tests makes it fairly
> easy to see what is being tested, and what is the expected behavior.
> 
> Have fun! :)
> 
> ...Johan
> 
> 
>  t/t7410-submodule-update-scenarios.sh | 2859 +++++++++++++++++++++++++++++++++
>  1 file changed, 2859 insertions(+)
>  create mode 100755 t/t7410-submodule-update-scenarios.sh
> 
> diff --git a/t/t7410-submodule-update-scenarios.sh b/t/t7410-submodule-update-scenarios.sh
> new file mode 100755
> index 0000000..22056cc
> --- /dev/null
> +++ b/t/t7410-submodule-update-scenarios.sh
> @@ -0,0 +1,2859 @@
> +#!/bin/sh
> +#
> +# Copyright (c) 2014 Johan Herland
> +#
> +
> +test_description='Test "git submodule update" in a variety of scenarios
> +
> +This test attempts to map out the various scenarios in which submodule update
> +is run, and verify their expected behaviour (according to the git submodule
> +documentation).
> +'
> +
> +. ./test-lib.sh
> +
> +# First a textual representation of the various cases we are testing:
> +#
> +# The factors/variables being explored are:
> +#  - submodule.sub.branch
> +#     1.* - unset
> +#     2.* - == foo (exists upstream)
> +#     3.* - == bar (MISSING upstream)
> +#  - submodule.sub.update
> +#     ?.1.* - none
> +#     ?.2.* - checkout
> +#     ?.3.* - merge
> +#     ?.4.* - rebase
> +#     ?.5.* - !command
> +#  - remote mode (whether or not --remote is given on command-line)
> +#     ?.?.1.* - disabled
> +#     ?.?.2.* - enabled
> +#  - current state of submodule:
> +#     ?.?.?.1 - not yet cloned
> +#     ?.?.?.2 - cloned, detached, HEAD == gitlink
> +#     ?.?.?.3 - cloned, detached, HEAD != gitlink
> +#     ?.?.?.4 - cloned, on branch foo (exists upstream), HEAD == gitlink
> +#     ?.?.?.5 - cloned, on branch foo (exists upstream), HEAD != gitlink
> +#     ?.?.?.6 - cloned, on branch bar (MISSING upstream), HEAD == gitlink
> +#     ?.?.?.7 - cloned, on branch bar (MISSING upstream), HEAD != gitlink
> +#
> +# The above variables are combined to enumerate all possible cases, from
> +# 1.1.1.1 to 3.5.2.7 (yes, that's 210 separate test cases). Each test case is
> +# named with its number followed by a short description of its expected outcome.
> +
> +# TODO ITEMS:
> +#
> +# T1: Rename "master" branch to "default" to test correct behaviour when
> +#     submodule's upstream has no master branch.
> +#     Affects: pre, 1.3.1.1, 1.3.2.1, 1.4.1.1, 1.4.2.1
> +#
> +# T2: Test with submodule.<name>.url != submodule's remote.origin.url. Does
> +#     "submodule update --remote" sync with submodule.<name>.url, or with the
> +#     submodule's origin? (or with the submodule's current branch's upstream)?
> +#
> +# T3: Fix uninitialized submodule state after attempting to clone from upstream
> +#     where .branch is missing.
> +#     Affects: pre, 3.2.2.1, 3.3.2.1, 3.4.2.1, 3.5.2.1
> +
> +# DISCUSSION ITEMS:
> +#
> +# D1: When submodule is already at right commit, checkout-mode currently does
> +#     nothing. Should it instead detach, even when no update is needed?
> +#     Affects: 1.2.1.4, 1.2.1.6, 2.2.1.4, 2.2.1.6, 3.2.1.4, 3.2.1.6
> +#
> +# D2: Should all/some of 1.3.*/1.4.* abort/error because we don't know what to
> +#     merge/rebase with (because .branch is unset)? Or is the current default
> +#     to origin/HEAD OK?
> +#     Affects: 1.3.*, 1.4.*
> +#
> +# D3: When submodule is already at right commit, merge/rebase-mode currently
> +#     does nothing. Should it do something else (e.g. not leave submodule
> +#     detached, or checked out on the "wrong" branch (i.e. != .branch))?
> +#     (This discussion point is related to D1, D5 and D6)
> +#     Affects: 1.3.1.2, 1.3.1.4, 1.3.1.6,
> +#              1.4.1.2, 1.4.1.4, 1.4.1.6,
> +#              2.3.1.2, 2.3.1.4, 2.3.1.6, 2.3.2.3, 2.3.2.5, 2.3.2.7,
> +#              2.4.1.2, 2.4.1.4, 2.4.1.6, 2.4.2.3, 2.4.2.5, 2.4.2.7,
> +#              3.3.1.2, 3.3.1.4, 3.3.1.6
> +#              3.4.1.2, 3.4.1.4, 3.4.1.6
> +#
> +# D4: When 'submodule update' performs a clone to populate a submodule, it
> +#     currently also creates a default branch (named after origin/HEAD) in
> +#     that submodule, EVEN WHEN THAT BRANCH WILL NEVER BE USED (e.g. because
> +#     we're in checkout-mode and submodule will always be detached). Is this
> +#     good, or should the clone performed by 'submodule update' skip the
> +#     automatic local branch creation?
> +#     Affects: 1.2.*.1, 1.3.*.1, 1.4.*.1, 1.5.*.1,
> +#              2.2.*.1, 2.3.*.1, 2.4.*.1, 2.5.*.1,
> +#              3.2.1.1, 3.3.1.1, 3.4.1.1, 3.5.1.1
> +#
> +# D5: When in merge/rebase-mode, and 'submodule update' actually ends up doing
> +#     a merge/rebase, that will happen on the current branch (or detached HEAD)
> +#     and NOT on the configured (or default) .branch. Is this OK? Should we
> +#     abort (or at least warn) instead? (In general, .branch seems only to
> +#     affect the submodule's HEAD when the submodule is first cloned.)
> +#     (This discussion point is related to D3 and D6)
> +#     Affects: 1.3.1.3, 1.3.1.5, 1.3.1.7, 1.3.2.>=2,
> +#              1.4.1.3, 1.4.1.5, 1.4.1.7, 1.4.2.>=2,
> +#              2.3.1.3, 2.3.1.5, 2.3.1.7, 2.3.2.2, 2.3.2.4, 2.3.2.6,
> +#              2.4.1.3, 2.4.1.5, 2.4.1.7, 2.4.2.2, 2.4.2.4, 2.4.2.6
> +#              3.3.1.3, 3.3.1.5, 3.3.1.7
> +#              3.4.1.3, 3.4.1.5, 3.4.1.7
> +#
> +# D6: The meaning of submodule.<name>.branch is initially confusing, as it does
> +#     not really concern the submodule's local branch (except as a naming hint
> +#     when the submodule is first cloned). Instead, submodule.<name>.branch is
> +#     really about which branch in the _upstream_ submodule (as defined by
> +#     submodule.<name>.url, or by the submodule's remote.origin.url?) that we
> +#     want to integrate with. This is probably the more useful setting, and it
> +#     becomes obviously correct after (re-)reading gitmodules(5) and
> +#     git-config(1). However, from just reading the "update" section in
> +#     git-submodule(1) (or not even that), things are not so clear-cut. Would
> +#     submodule.<name>.upstream (or .remote-branch, or similar) be a better
> +#     name for this?
> +#
> +# D7: What to do when .branch refers to a branch that is missing from upstream?
> +#     Currently, when trying to clone, the clone fails (which causes 'git
> +#     submodule update --remote' to fail), but leaves the submodule in an
> +#     uninitialized state (there is a .git, but the work tree is missing).
> +#     This is probably not the behavior we want...
> +#     Affects: pre, 3.2.2.1, 3.3.2.1, 3.4.2.1, 3.5.2.1
> +
> +# First, we need to setup the environment in which the test cases are run.
> +# This consists of an upstream super-repo containing a single submodule.
> +# The submodule commit graph looks like this:
> +#
> +#   $root_commit --->  $old_commit ---> $new_commit  <- master (HEAD) # T1
> +#                \          ^- (superproject's gitlink points here)
> +#                 --> $foo_commit  <- foo
> +#
> +# Each test case then starts by cloning upstream_super -> super and setting up
> +# its submodule + configuration according to the current test case. It then
> +# runs "git submodule update" (with or without --remote) and verifies the
> +# expected results.
> +
> +test_expect_success 'preliminaries: setup upstream super and sub' '
> +	git init upstream_sub &&
> +	(cd upstream_sub &&
> +	 test_commit root_commit &&
> +	 test_commit foo_commit &&
> +	 git branch foo &&
> +	 git reset --hard HEAD^ &&
> +#	 git branch -m default &&  # T1
> +	 test_commit old_commit
> +	) &&
> +	git init upstream_super &&
> +	(cd upstream_super &&
> +	 git submodule add ../upstream_sub sub &&
> +	 test_tick &&
> +	 git commit -m "Add sub"
> +	) &&
> +	(cd upstream_sub &&
> +	 test_commit new_commit
> +	)
> +'
> +
> +# The following commit IDs are used in various test cases
> +root_commit=$(git -C upstream_sub rev-parse --verify -q root_commit)
> +foo_commit=$(git -C upstream_sub rev-parse --verify -q foo_commit)
> +old_commit=$(git -C upstream_sub rev-parse --verify -q old_commit)
> +new_commit=$(git -C upstream_sub rev-parse --verify -q new_commit)
> +
> +fail()
> +{
> +	echo "$@"
> +	false
> +}
> +
> +# Verify that the path in $1 contains a cloned git repo
> +verify_is_cloned()
> +{
> +	test -e "$1/.git" ||
> +		fail "Failed to find cloned repo at '$1'"
> +}
> +
> +# Verify that commit $2 in repo $1 has parents $3, $4, ... (in the given order).
> +verify_parents()
> +{
> +	repo=$1; shift
> +	commit=$1; shift
> +	expect_p=$@
> +	actual_p=$(git --git-dir="$repo/.git" log --format=%P -1 "$commit")
> +	test "$expect_p" = "$actual_p" ||
> +		fail "Expected $commit parents '$expect_p' != '$actual_p'"
> +}
> +
> +# Verify that HEAD in repo $1 points to commit $2.
> +# If $2 is of the form 'parents.<SHA1>[.<SHA1>...]', then check that HEAD
> +# currently points to a commit whose parents are the given SHA1s (in order).
> +verify_head()
> +{
> +	head=$(git --git-dir="$1/.git" rev-parse -q HEAD)
> +	case "$2" in
> +	parents.*)
> +		parents=$(echo "$2" | sed -e 's/^parents\.//' -e 's/\./ /g')
> +		verify_parents "$1" "$head" $parents ||
> +			fail "Failed to verify parents of HEAD in '$1'"
> +		;;
> +	*)
> +		test "$2" = "$head" ||
> +			fail "Expected HEAD in '$1' to be '$2', but is '$head'"
> +	esac
> +}
> +
> +# Verify that the repo in $1 is currently checked out on branch $2.
> +# If $2 is "detached", verify that $1'a HEAD is in fact detached.
> +verify_branch()
> +{
> +	expect=$2
> +	if test "$expect" = "detached"
> +	then
> +		expect=
> +	fi
> +	actual=$(git --git-dir="$1/.git" symbolic-ref --short -q HEAD)
> +	test "$expect" = "$actual" ||
> +		fail "Expected branch in '$1' to be '$expect', but is '$actual'"
> +}
> +
> +# Clone upstream_super to super, and run "git submodule init"
> +setup_super()
> +{
> +	rm -rf super &&
> +	git clone upstream_super super &&
> +	(cd super &&
> +	 git submodule init &&
> +	 test_must_fail verify_is_cloned sub &&
> +	 test "$(git rev-parse -q HEAD:sub)" = "$old_commit"
> +	)
> +}
> +
> +# Setup submodule.sub.branch == $1
> +# If $1 == "unset", ensure submodule.sub.branch is unset
> +setup_sub_branch()
> +{
> +	if test "$1" = "unset"
> +	then
> +		git config --unset-all "submodule.sub.branch"
> +		test_must_fail git config "submodule.sub.branch" ||
> +			error "Failed to unset submodule.sub.branch"
> +	else
> +		git config "submodule.sub.branch" "$1"
> +		actual=$(git config "submodule.sub.branch")
> +		test "$actual" = "$1" ||
> +			error "Failed to set submodule.sub.branch to '$1'"
> +	fi
> +}
> +
> +# Setup submodule.sub.update == $1
> +setup_sub_update()
> +{
> +	git config "submodule.sub.update" "$1"
> +	actual=$(git config "submodule.sub.update")
> +	test "$actual" = "$1" ||
> +		error "Failed to set submodule.sub.update to '$1'"
> +}
> +
> +# Setup the state of the sub submodule according to $1, which is one of:
> +#  - "uncloned" - sub is an empty dir.
> +#  - "detach" - sub is detached at the commit in $2.
> +#  - * - sub is checked out on branch named in $1, at the commit in $2.
> +setup_sub_state()
> +{
> +	case "$1" in
> +	uncloned)
> +		test_must_fail verify_is_cloned sub ||
> +			error "Failed to verify uncloned sub"
> +		;;
> +	detach)
> +		git submodule update --checkout sub &&
> +		(cd sub &&
> +		 git checkout "$2"
> +		) &&
> +		verify_is_cloned sub &&
> +		verify_branch sub detached &&
> +		verify_head sub "$2" ||
> +			error "Failed to detach sub at '$2'"
> +		;;
> +	*)
> +		git submodule update --checkout sub &&
> +		(cd sub &&
> +		 git checkout -b "$1" "$2"
> +		) &&
> +		verify_is_cloned sub &&
> +		verify_branch sub "$1" &&
> +		verify_head sub "$2" ||
> +			error "Failed to attach sub to '$1' at '$2'"
> +	esac
> +}
> +
> +# Verify the state of the sub submodule according to $1, which is one of:
> +#  - "uncloned" - sub is an empty dir.
> +#  - "detach" - sub is detached at the commit in $2.
> +#  - * - sub is checked out on branch named in $1, at the commit in $2.
> +# If $2 is of the form 'parents.<SHA1>[.<SHA1>...]', then check that HEAD
> +# currently points to a commit whose parents are the given SHA1s (in order).
> +verify_sub_state()
> +{
> +	case "$1" in
> +	uncloned)
> +		test_must_fail verify_is_cloned sub ||
> +			fail "Failed to verify uncloned sub"
> +		;;
> +	detach)
> +		verify_is_cloned sub &&
> +		verify_branch sub detached &&
> +		verify_head sub "$2" ||
> +			fail "Failed to verify detached sub at '$2'"
> +		;;
> +	*)
> +		verify_is_cloned sub &&
> +		verify_branch sub "$1" &&
> +		verify_head sub "$2" ||
> +			fail "Failed to verify attached sub at '$1' -> '$2'"
> +	esac
> +}
> +
> +verify_sub_patch_id()
> +{
> +	p1=$(git --git-dir=sub/.git show $1 | git patch-id | cut -d' ' -f1)
> +	p2=$(git --git-dir=sub/.git show $2 | git patch-id | cut -d' ' -f1)
> +	test "$p1" = "$p2" ||
> +		fail "'$1' and '$2' has different patch-ids ('$p1' != '$p2')"
> +}
> +
> +# 1.1.* - .branch is unset, .update == none
> +
> +test_expect_success '1.1.1.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '1.1.1.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.1.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.1.1.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.1.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.1.1.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.1.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '1.1.2.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '1.1.2.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 1.2.* - .branch is unset, .update == checkout
> +
> +test_expect_success '1.2.1.1 - clone, detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4
> +	)
> +'
> +
> +test_expect_success '1.2.1.2 - already @ $old_commit -> keep detached' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.1.3 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.1.4 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.1.5 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.1.6 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.1.7 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.1 - clone, detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit # D4
> +	)
> +'
> +
> +test_expect_success '1.2.2.2 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.3 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.4 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.5 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.6 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.2.2.7 - detach @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +# 1.3.* - .branch is unset, .update == merge # D2
> +
> +test_expect_success '1.3.1.1 - clone, create branch named from origin/HEAD @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +test_expect_success '1.3.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.1.3 - merge $old_commit -> $foo_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.1.5 - merge $old_commit -> $foo_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.1.7 - merge $old_commit -> $foo_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.1 - clone, create branch from origin/HEAD @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +test_expect_success '1.3.2.2 - ffwd $old_commit -> $new_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.3 - merge $new_commit -> $foo_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach parents.$foo_commit.$new_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.4 - ffwd $old_commit -> $new_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $new_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.5 - merge $new_commit -> $foo_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo parents.$foo_commit.$new_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.6 - ffwd $old_commit -> $new_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $new_commit
> +	)
> +'
> +
> +test_expect_success '1.3.2.7 - merge $new_commit -> $foo_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar parents.$foo_commit.$new_commit
> +	)
> +'
> +
> +# 1.4.* - .branch is unset, .update == rebase # D2
> +
> +test_expect_success '1.4.1.1 - clone, create branch named from origin/HEAD @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +test_expect_success '1.4.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '1.4.1.3 - rebase $foo_commit onto $old_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.4.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '1.4.1.5 - rebase $foo_commit onto $old_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.4.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '1.4.1.7 - rebase $foo_commit onto $old_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.1 - clone, create branch from origin/HEAD @ $new_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +test_expect_success '1.4.2.2 - ffwd $old_commit -> $new_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.3 - rebase $foo_commit onto $new_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach parents.$new_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.4 - ffwd $old_commit -> $new_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $new_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.5 - rebase $foo_commit onto $new_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo parents.$new_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.6 - ffwd $old_commit -> $new_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $new_commit
> +	)
> +'
> +
> +test_expect_success '1.4.2.7 - rebase $foo_commit onto $new_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar parents.$new_commit
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +# 1.5.* - .branch is unset, .update == !command
> +
> +test_expect_success '1.5.1.1 - clone, create branch named from origin/HEAD @ $old_commit. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch unset &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +test_expect_success '1.5.1.2 - already at $old_commit, remain detached. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch unset &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.1.3 - !command invoked to integrate $old_commit -> $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '1.5.1.4 - already at $old_commit, remain attached to foo. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.1.5 - !command invoked to integrate $old_commit -> foo/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '1.5.1.6 - already at $old_commit, remain attached to bar. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.1.7 - !command invoked to integrate $old_commit -> bar/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '1.5.2.1 - clone, create branch from origin/HEAD @ $new_commit. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $new_commit # T1, D4, FIXME: s/detach/master/?
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $old_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.2 - !command invoked to integrate $new_commit -> $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $foo_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.3 - !command invoked to integrate $new_commit -> $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $old_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.4 - !command invoked to integrate $new_commit -> foo/$old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $foo_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.5 - !command invoked to integrate $new_commit -> foo/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $old_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.6 - !command invoked to integrate $new_commit -> bar/$old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $foo_commit, and asked to integrate $new_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$new_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '1.5.2.7 - !command invoked to integrate $new_commit -> bar/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch unset &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +# 2.1.* - .branch == foo (exists upstream), .update == none
> +
> +test_expect_success '2.1.1.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '2.1.1.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.1.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.1.1.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.1.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.1.1.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.1.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '2.1.2.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '2.1.2.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 2.2.* - .branch == foo (exists upstream), .update == checkout
> +
> +test_expect_success '2.2.1.1 - clone, detach @ $old_commit (.branch is ignored)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4
> +	)
> +'
> +
> +test_expect_success '2.2.1.2 - already @ $old_commit -> keep detached' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.1.3 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.1.4 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.1.5 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.1.6 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.1.7 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.1 - clone, detach @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit # D4
> +	)
> +'
> +
> +test_expect_success '2.2.2.2 - detach @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.3 - already @ $foo_commit, remain detached' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.4 - detach @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.5 - already @ $foo_commit, remain attached to foo' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.6 - detach @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.2.2.7 - already @ $foo_commit, remain attached to bar' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 2.3.* - .branch == foo (exists upstream), .update == merge
> +
> +test_expect_success '2.3.1.1 - clone, create branch called foo @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +test_expect_success '2.3.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.1.3 - merge $old_commit -> $foo_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.1.5 - merge $old_commit -> $foo_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.1.7 - merge $old_commit -> $foo_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.1 - clone, create branch from origin/foo @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +test_expect_success '2.3.2.2 - merge $foo_commit -> $old_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach parents.$old_commit.$foo_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.3 - already @ $foo_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.4 - merge $foo_commit -> $old_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo parents.$old_commit.$foo_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.5 - already @ $foo_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.6 - merge $foo_commit -> $old_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar parents.$old_commit.$foo_commit
> +	)
> +'
> +
> +test_expect_success '2.3.2.7 - already @ $foo_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 2.4.* - .branch == foo (exists upstream), .update == rebase
> +
> +test_expect_success '2.4.1.1 - clone, create branch called foo @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +test_expect_success '2.4.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.1.3 - rebase $foo_commit onto $old_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.4.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.1.5 - rebase $foo_commit onto $old_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.4.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.1.7 - rebase $foo_commit onto $old_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.1 - clone, create branch from origin/foo @ $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +test_expect_success '2.4.2.2 - rebase $old_commit onto $foo_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach parents.$foo_commit &&
> +	 verify_sub_patch_id HEAD $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.3 - already @ $foo_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.4 - rebase $old_commit onto $foo_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo parents.$foo_commit &&
> +	 verify_sub_patch_id HEAD $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.5 - already @ $foo_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.6 - rebase $old_commit onto $foo_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar parents.$foo_commit &&
> +	 verify_sub_patch_id HEAD $old_commit
> +	)
> +'
> +
> +test_expect_success '2.4.2.7 - already @ $foo_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 2.5.* - .branch == foo (exists upstream), .update == !command
> +
> +test_expect_success '2.5.1.1 - clone, create branch called foo @ $old_commit. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +test_expect_success '2.5.1.2 - already at $old_commit, remain detached. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.1.3 - !command invoked to integrate $old_commit -> $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.1.4 - already at $old_commit, remain attached to foo. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.1.5 - !command invoked to integrate $old_commit -> foo/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.1.6 - already at $old_commit, remain attached to bar. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.1.7 - !command invoked to integrate $old_commit -> bar/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.2.1 - clone, create branch from origin/foo @ $foo_commit. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit # D4, FIXME: s/detach/foo/?
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $old_commit, and asked to integrate $foo_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$foo_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.2.2 - !command invoked to integrate $foo_commit -> $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.2.3 - already at $foo_commit, remain detached. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $old_commit, and asked to integrate $foo_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$foo_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.2.4 - !command invoked to integrate $foo_commit -> foo/$old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.2.5 - already at $foo_commit, remain attached to foo. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $old_commit, and asked to integrate $foo_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$old_commit" &&
> +test "\$1" = "$foo_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '2.5.2.6 - !command invoked to integrate $foo_commit -> bar/$old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '2.5.2.7 - already at $foo_commit, remain attached to bar. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch foo &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 3.1.* - .branch == bar (MISSING upstream), .update == none
> +
> +test_expect_success '3.1.1.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.1.1.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.1.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.1.1.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.1.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.1.1.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.1.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.1 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.1.2.2 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.3 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.4 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.5 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.6 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.1.2.7 - do nothing (.update == none)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update none &&
> +	 setup_sub_branch bar &&
> +	 git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 3.2.* - .branch == bar (MISSING upstream), .update == checkout
> +
> +test_expect_success '3.2.1.1 - clone, detach @ $old_commit (.branch is ignored)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4
> +	)
> +'
> +
> +test_expect_success '3.2.1.2 - already @ $old_commit -> keep detached' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.1.3 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.1.4 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.1.5 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.1.6 - already @ $old_commit -> keep attached' ' # D1
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.1.7 - detach @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_failure '3.2.2.1 - fail to clone (remote branch bar missing), leave uncloned' ' # T3, D7
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.2.2.2 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.2.3 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.2.2.4 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.2.5 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.2.2.6 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.2.2.7 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update checkout &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 3.3.* - .branch == bar (MISSING upstream), .update == merge
> +
> +test_expect_success '3.3.1.1 - clone, create branch called bar @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/bar/?
> +	)
> +'
> +
> +test_expect_success '3.3.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.1.3 - merge $old_commit -> $foo_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.1.5 - merge $old_commit -> $foo_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.1.7 - merge $old_commit -> $foo_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$foo_commit.$old_commit
> +	)
> +'
> +
> +test_expect_failure '3.3.2.1 - fail to clone (remote branch bar missing), leave uncloned' ' # T3, D7
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.3.2.2 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.2.3 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.3.2.4 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.2.5 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.3.2.6 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.3.2.7 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update merge &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 3.4.* - .branch == bar (MISSING upstream), .update == rebase
> +
> +test_expect_success '3.4.1.1 - clone, create branch called bar @ $old_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/bar/?
> +	)
> +'
> +
> +test_expect_success '3.4.1.2 - already at $old_commit, remain detached' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.1.3 - rebase $foo_commit onto $old_commit, remain detached' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state detach parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.4.1.4 - already at $old_commit, remain attached to foo' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.1.5 - rebase $foo_commit onto $old_commit, remain attached to foo' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.4.1.6 - already at $old_commit, remain attached to bar' ' # D3
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.1.7 - rebase $foo_commit onto $old_commit, remain attached to bar' ' # D5
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar parents.$old_commit &&
> +	 verify_sub_patch_id HEAD $foo_commit
> +	)
> +'
> +
> +test_expect_failure '3.4.2.1 - fail to clone (remote branch bar missing), leave uncloned' ' # T3, D7
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.4.2.2 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.2.3 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.4.2.4 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.2.5 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.4.2.6 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.4.2.7 - fail (remote branch bar missing)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update rebase &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +# 3.5.* - .branch == bar (MISSING upstream), .update == !command
> +
> +test_expect_success '3.5.1.1 - clone, create branch called bat @ $old_commit. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit # D4, FIXME: s/detach/bar/?
> +	)
> +'
> +
> +test_expect_success '3.5.1.2 - already at $old_commit, remain detached. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 git submodule update && # should not invoke "false"
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: detached @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '3.5.1.3 - !command invoked to integrate $old_commit -> $foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '3.5.1.4 - already at $old_commit, remain attached to foo. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to foo @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "foo" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '3.5.1.5 - !command invoked to integrate $old_commit -> foo/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_success '3.5.1.6 - already at $old_commit, remain attached to bar. !command is NOT invoked' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +cat > test_command.sh <<EOF
> +#!/bin/sh
> +# Verify: attached to bar @ $foo_commit, and asked to integrate $old_commit
> +test "\$(git symbolic-ref --short -q HEAD)" = "bar" &&
> +test "\$(git rev-parse -q --verify HEAD)" = "$foo_commit" &&
> +test "\$1" = "$old_commit" &&
> +git checkout -b success $root_commit
> +EOF
> +chmod +x test_command.sh
> +
> +test_expect_success '3.5.1.7 - !command invoked to integrate $old_commit -> bar/$foo_commit' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !../../test_command.sh &&
> +	 setup_sub_branch bar &&
> +	 git submodule update &&
> +	 verify_sub_state success $root_commit # test_command.sh is happy
> +	)
> +'
> +
> +test_expect_failure '3.5.2.1 - fail to clone (remote branch bar missing), leave uncloned' ' # T3, D7
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state uncloned &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state uncloned
> +	)
> +'
> +
> +test_expect_success '3.5.2.2 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $old_commit
> +	)
> +'
> +
> +test_expect_success '3.5.2.3 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state detach $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state detach $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.5.2.4 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $old_commit
> +	)
> +'
> +
> +test_expect_success '3.5.2.5 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state foo $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state foo $foo_commit
> +	)
> +'
> +
> +test_expect_success '3.5.2.6 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $old_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $old_commit
> +	)
> +'
> +
> +test_expect_success '3.5.2.7 - fail (remote branch bar missing, !command not invoked)' '
> +	setup_super &&
> +	(cd super &&
> +	 setup_sub_state bar $foo_commit &&
> +	 setup_sub_update !false &&
> +	 setup_sub_branch bar &&
> +	 test_must_fail git submodule update --remote &&
> +	 verify_sub_state bar $foo_commit
> +	)
> +'
> +
> +test_done
>