hard working

doc.md

+https://www.atlassian.com/git/tutorials/git-subtree
+
+## Adding the sub-project as a remote
+
+Adding the subtree as a remote allows us to refer to it in shorter form:
+
+```
+git remote add -f git-subtree git@gitlab.isima.fr:vimazeno/git-subtree.git
+```
+
+Add the subtree by referring to the remote in short form:
+
+```
+git subtree add --prefix features/git-subtree git-subtree master --squash
+```
+
+Update git subtree anytime:
+
+```
+git fetch git-subtree master
+git subtree pull --prefix features/git-subtree git-subtree master --squash
+```
+
+## Contributing back upstream 
+
+record a merge so that we can track the entire tree history of the plug-in up to this point:
+
+```
+git merge -s ours --no-commit git-subtree/main
+```
+
+Read the content of the latest tree-object into the plugin repository into our working directory ready to be committed:
+
+```
+git read-tree --prefix=features/git-subtree -u git-subtree/main
+```
+
+commit on subtree
+
+```
+git ci -m"[subtree] adding new feature"
+```
+
+update git-subtree repo git pull -s subtree tpope-vim-surround main
\ No newline at end of file

features/git-subtree/fetaure

-a really cool feature
\ No newline at end of file
+a really cool feature
+another one
\ No newline at end of file