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|
# We will work from scratch to illustrate the process
$ cd ~/code/tmp
# OK, first set up our submodule
$ mkdir rubyspec
$ cd rubyspec
$ git init
Initialized empty Git repository in .git/
$ echo 'rubyspec' > README
$ git add README
$ git commit -a -m 'Initial import of rubyspec'
Created initial commit 4c43e66: Initial import of rubyspec
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 README
$ cd ..
# OK, now set up the 'public' rubyspec repo (rubyspec.com or whatever)
$ git clone --bare rubyspec rubyspec.git
Initialized empty Git repository in /Users/user/code/tmp/rubyspec.git/
# Next, we create the superproject, obviously the public rbx repo
# already exists in reality.
$ mkdir rbx
$ cd rbx
$ git init
Initialized empty Git repository in .git/
$ echo 'rbx' > README
$ git add README
$ git commit -a -m 'RBX import'
Created initial commit 43b9035: RBX import
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 README
$ cd ..
# OK, same deal here, make a 'public' repo (git://git.rubini.us in reality)
$ git clone --bare rbx rbx.git
Initialized empty Git repository in /Users/user/code/tmp/rbx.git/
# Now, let us get rid of the originals so we have a more realistic situation
$ rm -rf rbx rubyspec
$ ls
rbx.git rubyspec.git
# Next we want to set up the submodule link, and we need a real rbx repo
$ git clone rbx.git my_rbx
Initialized empty Git repository in /Users/user/code/tmp/my_rbx/.git/
$ cd my_rbx
$ ls
README
# Now we associate the submodule (in reality we would use the URI, not local path)
$ mkdir spec
# We can 'mount' the submodule anywhere in the repo, in this case it goes in spec/ruby/
$ git submodule add ~/code/tmp/rubyspec.git spec/ruby
Initialized empty Git repository in /Users/user/code/tmp/my_rbx/spec/ruby/.git/
$ ls -la
total 16
drwxr-xr-x 4 user group 204 Mar 12 19:39 .
drwxr-xr-x 7 user group 238 Mar 12 19:37 ..
drwxr-xr-x 7 user group 374 Mar 12 19:39 .git
-rw-r--r-- 1 user group 85 Mar 12 19:39 .gitmodules
-rw-r--r-- 1 user group 4 Mar 12 19:37 README
drwxr-xr-x 3 user group 102 Mar 12 19:39 spec
# .gitmodules has the tracking info
$ cat .gitmodules
[submodule "spec/ruby"]
path = spec/ruby
url = /Users/user/code/tmp/rubyspec.git
# Our rubyspec repo should be in place now
$ ls -la spec/ruby
total 8
drwxr-xr-x 3 user group 136 Mar 12 19:39 .
drwxr-xr-x 3 user group 102 Mar 12 19:39 ..
drwxr-xr-x 7 user group 374 Mar 12 19:39 .git
-rw-r--r-- 1 user group 9 Mar 12 19:39 README
$ cat spec/ruby/README
rubyspec
# Now we need to record the submodule in the superproject
$ git status
On branch master
Changes to be committed:
(use "git reset HEAD <file>..." to unstage)
new file: .gitmodules
new file: spec/ruby
$ git commit -m 'Imported rubyspec submodule'
Created commit 0ae5cd3: Imported rubyspec submodule
2 files changed, 4 insertions(+), 0 deletions(-)
create mode 100644 .gitmodules
create mode 160000 spec/ruby
# And then record this over at the mainline
$ git push
Counting objects: 5, done.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (4/4), 439 bytes, done.
Total 4 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (4/4), done.
To /Users/user/code/tmp/rbx.git
43b9035..0ae5cd3 master -> master
$ cd ..
# Alright. Now, our test situation is that Joe just hacks on rubyspec and
# Bob hacks on rubyspec as a part of rbx!
# Let us create Bob's repo quick first:
$ git clone rbx.git bobs_rbx
$ cd bobs_rbx
$ ls -la
total 8
drwxr-xr-x 4 user group 204 Mar 12 19:47 .
drwxr-xr-x 9 user group 306 Mar 12 19:44 ..
drwxr-xr-x 7 user group 374 Mar 12 19:44 .git
-rw-r--r-- 1 user group 85 Mar 12 19:44 .gitmodules
-rw-r--r-- 1 user group 0 Mar 12 19:45 README
drwxr-xr-x 3 user group 102 Mar 12 19:44 spec
# Now, as you can see, a pristine checkout of a superproject will not actually contain the submodule code
$ ls -la spec/ruby
total 0
drwxr-xr-x 2 user group 68 Mar 12 19:44 .
drwxr-xr-x 3 user group 102 Mar 12 19:44 ..
# We need to first init to properly link the modules and then update to pull the data in
$ git submodule init
Submodule 'spec/ruby' (/Users/user/code/tmp/rubyspec.git) registered for path 'spec/ruby'
$ git submodule update
Initialized empty Git repository in /Users/user/code/tmp/bobs_rbx/spec/ruby/.git/
Submodule path 'spec/ruby': checked out '4c43e665381054478aa7c82da1d1d63b5c258e4b'
$ ls -la spec/ruby
total 8
drwxr-xr-x 3 user group 136 Mar 12 19:48 .
drwxr-xr-x 3 user group 102 Mar 12 19:48 ..
drwxr-xr-x 7 user group 408 Mar 12 19:48 .git
-rw-r--r-- 1 user group 9 Mar 12 19:48 README
# OK, now it is there. Let us hop out of here for a bit.
$ cd ..
# Now, Joe is doing some work on his repo which is JUST the rubyspec submodule
$ git clone rubyspec.git joes_spec
Initialized empty Git repository in /Users/user/code/tmp/joes_spec/.git/
$ cd joes_spec
$ ls
README
# OK, Joe makes a change
$ echo 'new spec' > spec.rb
$ git add spec.rb
$ git commit -m 'Added spec.rb'
Created commit f380258: Added spec.rb
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 spec.rb
# Joe pushes to mainline of rubyspec
$ git push
Counting objects: 4, done.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 290 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
To /Users/user/code/tmp/rubyspec.git
4c43e66..f380258 master -> master
# Now, let us check in with Bob who has his clone of the rbx repo
$ cd bobs_rbx
# Bob does not have Joe's spec yet
$ ls -la spec/ruby/
total 8
drwxr-xr-x 3 user group 136 Mar 12 19:48 .
drwxr-xr-x 3 user group 102 Mar 12 19:48 ..
drwxr-xr-x 7 user group 408 Mar 12 19:48 .git
-rw-r--r-- 1 user group 9 Mar 12 19:48 README
# Updating does not seem to work either!
$ git submodule update
$ ls -la spec/ruby/
total 8
drwxr-xr-x 3 user group 136 Mar 12 19:48 .
drwxr-xr-x 3 user group 102 Mar 12 19:48 ..
drwxr-xr-x 7 user group 408 Mar 12 19:48 .git
-rw-r--r-- 1 user group 9 Mar 12 19:48 README
# Did Joe's change get registered? Let us check..
$ cd ..
$ git clone rubyspec.git check_joes_change
Initialized empty Git repository in /Users/user/code/tmp/check_joes_change/.git/
$ ls check_joes_change/
README spec.rb
# Yep, it is there! So what is going on?
# Right, we need to update the mainline rbx. Technically Bob could actually do this
# too but for now, let us pretend that some access control allows only me to make
# that update. So back to my repo.
$ cd my_rbx/
$
# Now, we need to grab the change first
$ cd spec/ruby/
$ ls
README
$ git status
On branch master
nothing to commit (working directory clean)
$ git pull
remote: Counting objects: 4, done.
remote: Compressing objects: 100% (2/2)remote: , done.
remote: Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
From /Users/user/code/tmp/rubyspec
4c43e66..f380258 master -> origin/master
Updating 4c43e66..f380258
Fast forward
spec.rb | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 spec.rb
$ ls -la
total 16
drwxr-xr-x 3 user group 170 Mar 12 19:54 .
drwxr-xr-x 3 user group 102 Mar 12 19:39 ..
drwxr-xr-x 7 user group 442 Mar 12 19:54 .git
-rw-r--r-- 1 user group 9 Mar 12 19:39 README
-rw-r--r-- 1 user group 9 Mar 12 19:54 spec.rb
# OK, there it is!
$ cd ../../
# So, need to record this update in the superproject
$ git status
On branch master
Changed but not updated:
(use "git add <file>..." to update what will be committed)
modified: spec/ruby
no changes added to commit (use "git add" and/or "git commit -a")
$ git add spec/ruby
$ git commit -m 'Updated our rubyspec checkout to newest version'
Created commit 0d96517: Updated our rubyspec checkout to newest version
1 files changed, 1 insertions(+), 1 deletions(-)
# And then push this change to mainline
$ git push
Counting objects: 5, done.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 319 bytes, done.
Total 3 (delta 1), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
To /Users/user/code/tmp/rbx.git
0ae5cd3..0d96517 master -> master
$ cd ..
$ cd bobs_rbx/
# NOW Bob should be able to access it
$ git submodule update
# No? How about this:
$ git pull
remote: Counting objects: 5, done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 3 (delta 1), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
From /Users/user/code/tmp/rbx
0ae5cd3..0d96517 master -> origin/master
Updating 0ae5cd3..0d96517
README: needs update
Fast forward
spec/ruby | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
# That by itself does not update yet
$ ls -la spec/ruby
total 8
drwxr-xr-x 3 user group 136 Mar 12 19:48 .
drwxr-xr-x 3 user group 102 Mar 12 19:48 ..
drwxr-xr-x 7 user group 408 Mar 12 19:48 .git
-rw-r--r-- 1 user group 9 Mar 12 19:48 README
# Now we must update
$ git submodule update
Submodule path 'spec/ruby': checked out 'f38025812763dd8ee44beebcc0c8a3997c9aac0f'
# And now it is there
$ ls -la spec/ruby
total 16
drwxr-xr-x 3 user group 170 Mar 12 19:57 .
drwxr-xr-x 3 user group 102 Mar 12 19:48 ..
drwxr-xr-x 7 user group 408 Mar 12 19:57 .git
-rw-r--r-- 1 user group 9 Mar 12 19:48 README
-rw-r--r-- 1 user group 9 Mar 12 19:57 spec.rb
# And there we go, properly updated now
# Of course, Bob can make a few changes now too. Here is the only potential problem.
# First, change something in rbx.
$ echo 'RTFM' > INSTALL
$ git add INSTALL
$ git commit -m 'Installation instructions'
Created commit c0e6667: Installation instructions
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 INSTALL
$ git push
Counting objects: 4, done.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 361 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
To /Users/user/code/tmp/rbx.git
0d96517..c0e6667 master -> master
# That was normal. Now, what if Bob wants to make changes to rubyspec?
# He can make the changes normally. If he has commit access, he can
# just hop over and do so.
$ cd spec/ruby
$ ls
README spec.rb
# One notable thing is that this is a detached by default to avoid some problems, so
# Bob must go to a real branch.
$ git status
Not currently on any branch.
nothing to commit (working directory clean)
$ git checkout master
Previous HEAD position was b292add... Added a spec
Switched to branch "master"
$ echo 'my spec' > spec2.rb
$ git add spec2.rb
$ git commit -m 'Added a spec'
Created commit b1e7bdb: Added a spec
1 files changed, 1 insertions(+), 0 deletions(-)
create mode 100644 spec2.rb
# Now Bob can just push it if he has access
$ git push
Counting objects: 4, done.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 313 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
To /Users/user/code/tmp/rubyspec.git
f380258..b1e7bdb master -> master
# As the data shows, we directly updated the rubyspec project
$
# Obviously, if Bob did not have commit rights, he would do the normal git-format-patch dance instead
$
# Now, the problem
$ cd ../..
$ git status
On branch master
Changed but not updated:
(use "git add <file>..." to update what will be committed)
modified: spec/ruby
no changes added to commit (use "git add" and/or "git commit -a")
# This shows the change we made--and adding it is perfectly safe so long
# as we do it correctly. This is incorrect:
$ git add spec/ruby/
$ git status
On branch master
Changes to be committed:
(use "git reset HEAD <file>..." to unstage)
deleted: spec/ruby
new file: spec/ruby/README
new file: spec/ruby/spec.rb
new file: spec/ruby/spec2.rb
$ git reset --hard HEAD
HEAD is now at c0e6667... Installation instructions
# OK, so that is not good. The trailing / has git thinking this is a new
# path which overwrites the submodule. So, without:
$ git add spec/ruby
$ git status
On branch master
Changes to be committed:
(use "git reset HEAD <file>..." to unstage)
modified: spec/ruby
# So that worked fine. Now we can update mainline normally
$ git commit -m 'New spec in rubyspec, updated here and pushed to rubyspec mainline'
Created commit 3749f4b: New spec in rubyspec, updated here and pushed to rubyspec mainline
1 files changed, 1 insertions(+), 1 deletions(-)
$ git push
Counting objects: 5, done.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 331 bytes, done.
Total 3 (delta 1), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
To /Users/user/code/tmp/rbx.git
c0e6667..3749f4b master -> master
$
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