2 git

$ z git_demo # 表示下面的操作在 git_demo 文件夹中进行
$ mkdir demo-repo
$ git init demo-repo        
hint: Using 'master' as the name for the initial branch. This default branch name
hint: is subject to change. To configure the initial branch name to use in all
hint: of your new repositories, which will suppress this warning, call:
hint: 
hint:   git config --global init.defaultBranch <name>
hint: 
hint: Names commonly chosen instead of 'master' are 'main', 'trunk' and
hint: 'development'. The just-created branch can be renamed via this command:
hint: 
hint:   git branch -m <name>
$ # git config --global init.defaultBranch main # 比如我比较喜欢 main

$ tree . -a -L 2 # -a 展示隐藏文件，-L 指定最大显示层级
.
└── .git
    ├── FETCH_HEAD
    ├── HEAD
    ├── branches
    ├── config
    ├── description
    ├── hooks
    ├── info
    ├── objects
    └── refs

6 directories, 4 files

$ nano README.md
... edit ...
$ mkdir sub-repo
$ nano sub-repo 1.txt
... edit ...
$ git add README.md # 将指定路径下的文件（夹）放入暂存区中
$ git status # 查看当前 git repo 中的文件修改情况，一般可以用别名 `gst` 表示
On branch master

No commits yet

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)
        new file:   README.md

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        sub-repo/

$ git commit [path/to/file]]# 将会以默认设置的终端编辑器打开

Please enter the commit message for your changes.Lines starting
with '#' will be ignored,and an empty message aborts the commit.
#
# On branch master
#
# Initial commit
#
# Changes to be committed:
#     new file: README.md
#
# Untracked files:
#     sub-repo/

git commit {{[-m|--message]}} "{{message}}"

$ git commit -m "feat: initial the repo."
[master (root-commit) 8530407] feat: initial the repo.
 1 file changed, 3 insertions(+)
 create mode 100644 README.md
$ git status   
On branch master
Untracked files:
  (use "git add <file>..." to include in what will be committed)
        sub-repo/

nothing added to commit but untracked files present (use "git add" to track)
$ git log
commit 8530407208f35d44ff2c0919a5228d0c7c2ba5bb (HEAD -> master)
Author: qssg <qssgatcn@gmail.com>
Date:   Sat Mar 29 15:23:12 2025 +0800

    feat: initial the repo.

$ z demo-repo
$ mkdir docs
$ nano docs/index.md
$ git add docs
$ git commit -m "docs: init the docs"
$ git log
commit ff83dd5e5f2d742f93888e1fe6f2faeb65a56032 (HEAD -> master)
Author: qssg <qssgatcn@gmail.com>
Date:   Sat Mar 29 16:04:42 2025 +0800

    docs: init the docs

commit 8530407208f35d44ff2c0919a5228d0c7c2ba5bb
...

$ git show 8530407208f35d44ff2c0919a5228d0c7c2ba5bb # 在不引起误解的情况下，前面几个 hex char 即可
commit 8530407208f35d44ff2c0919a5228d0c7c2ba5bb
Author: qssg <qssgatcn@gmail.com>
Date:   Sat Mar 29 15:23:12 2025 +0800

    feat: initial the repo.

diff --git a/README.md b/README.md
new file mode 100644
index 0000000..675954d
--- /dev/null
+++ b/README.md
@@ -0,0 +1,3 @@
+# Demo Repo
+
+This is a repo for demostrating usage of git and git repo.

$ git checkout 8530        
Note: switching to '8530407208f35d44ff2c0919a5228d0c7c2ba5bb'. 

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by switching back to a branch.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -c with the switch command. Example:

  git switch -c <new-branch-name>

Or undo this operation with:

  git switch -

Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at 8530407 feat: initial the repo.

$ git switch -                                         
Previous HEAD position was 8530407 feat: initial the repo.
Switched to branch 'master'

$ git checkout -b dev [reference] # 基于 reference 创建并切换分支，默认为当前分支 
$ git branch # 查看分支
 *  dev
    master

$ mkdir docs/intro
$ vim docs/intro/index.md
$ git add -A
$ git commit -m "docs: add intro folder"
[dev c35e6ae] docs: add intro folder
 2 files changed, 4 insertions(+)
 create mode 100644 docs/intro/index.md
 create mode 100644 sub-repo/1.txt
$ gst                                   
On branch dev
nothing to commit, working tree clean

$ git checkout master # 已经存在的分支可以直接切换
$ gst                
On branch master
nothing to commit, working tree clean

$ git checkout master
$ touch docs/base_use.md
$ vim docs/adv_use.md
$ git add -A         
$ git checkout dev   
A       docs/adv_use.md
A       docs/base_use.md
Switched to branch 'dev'

$ git checkout master
$ # modify conflict.md, add, commit
$ git checkout dev
$ # modify conflict.md, add, commit
$ git merge dev      
Auto-merging docs/conflict.md
CONFLICT (content): Merge conflict in docs/conflict.md
Automatic merge failed; fix conflicts and then commit the result.

<<<<<<< HEAD
I am in the branch of master.
=======
I am in the branch of dev.
>>>>>>> dev

$ git add docs/conflict.md
$ git commit -m "feat: merge dev branch"

$ git log --graph --oneline --decorate --all
*   cfe89fa (HEAD -> master) feat: merge dev branch
|\  
| * a01626b (dev) docs: edit conflict.md dev
* | 4a6153a docs: edit conflict.md master
|/  
*   a1c02af (origin/master) docs: modify confilct
|\  
| * 464e513 docs: edit conflict.md master
* | 6a143e8 docs: edit conflict.md dev
|/  
* 8dc5a0d docs: rm intro; add conflict
* 26316b1 docs: add master conflict.md
*   bfe1e30 Merge branch 'dev' for testing
|\  
* | e82c994 docs: add adv/base_use.md
| | * 0273fe5 (refs/stash) WIP on dev: c35e6ae docs: add intro folder
| |/| 
| | * d0d0510 index on dev: c35e6ae docs: add intro folder
| |/  
| * c35e6ae docs: add intro folder
|/  
* ff83dd5 docs: init the docs
* 8530407 feat: initial the repo.

$ z demo-repo
$ cd sub-repo && mkdir submod
$ git init submod
Initialized empty Git repository in ~/demo/git_demo/demo-repo/sub-repo/submod/.git/
$ vim submod/1.txt # 写入一些东西
$ git add -A
warning: adding embedded git repository: sub-repo/submod
hint: You've added another git repository inside your current repository.
hint: Clones of the outer repository will not contain the contents of
hint: the embedded repository and will not know how to obtain it.
hint: If you meant to add a submodule, use:
hint: 
hint:   git submodule add <url> sub-repo/submod
hint: 
hint: If you added this path by mistake, you can remove it from the
hint: index with:
hint: 
hint:   git rm --cached sub-repo/submod
hint: 
hint: See "git help submodule" for more information.

$ git submodule add ./sub-repo/submod sub-repo/submod 
fatal: 'sub-repo/submod' already exists in the index
# 这需要我们把之前暂存区的内容先清空
$ git rm -rf --cached "sub-repo"
rm 'sub-repo/1.txt'
rm 'sub-repo/submod'
$ git submodule add ./sub-repo/submod sub-repo/submod
Adding existing repo at 'sub-repo/submod' to the index

$ batcat .gitmodules 
───────┬───────────────────────────────────────────────────────────────────────────
       │ File: .gitmodules
───────┼───────────────────────────────────────────────────────────────────────────
   1   │ [submodule "sub-repo/submod"]
   2   │     path = sub-repo/submod
   3   │     url = ./sub-repo/submod
───────┴───────────────────────────────────────────────────────────────────────────
$ git submodule status                               
 f91d9559ac1f386ddb1876d63c0932e6584cad6b sub-repo/submod (heads/main)

$ tldr git submodule
git submodule
Inspects, updates and manages submodules.More information: https://git-scm.com/docs/git-submodule.

 - Install a repository's specified submodules:
   git submodule update --init --recursive

 - Add a Git repository as a submodule:
   git submodule add {{repository_url}}

 - Add a Git repository as a submodule at the specified directory:
   git submodule add {{repository_url}} {{path/to/directory}}

 - Update every submodule to its latest commit:
   git submodule foreach git pull

~/demo/git_demo/demo-repo master
$ git submodule add https://github.com/darstib/darstib.git github-resume
Cloning into '/home/qssg/demo/git_demo/demo-repo/github-resume'...
remote: Enumerating objects: 120, done.
remote: Counting objects: 100% (4/4), done.
remote: Compressing objects: 100% (3/3), done.
remote: Total 120 (delta 1), reused 4 (delta 1), pack-reused 116 (from 1)
Receiving objects: 100% (120/120), 7.87 MiB | 1024.00 KiB/s, done.
Resolving deltas: 100% (23/23), done.
$ ls
README.md  docs  github-resume  sub-repo

$ git mv github-resume sub-repo/github-resume

# Remove the submodule entry from .git/config
$ git submodule deinit -f path/to/submodule
# Remove the submodule directory from the superproject's .git/modules directory
$ rm -rf .git/modules/path/to/submodule
# Remove the entry in .gitmodules and remove the submodule directory located at path/to/submodule
$ git rm -f path/to/submodule

$ tldr git remote
git remote
Manage set of tracked repositories ("remotes").More information: https://git-scm.com/docs/git-remote.

 - List existing remotes with their names and URLs:
   git remote {{[-v|--verbose]}}

 - Add a remote:
   git remote add {{remote_name}} {{remote_url}}

 - Change the URL of a remote (use --add to keep the existing URL):
   git remote set-url {{remote_name}} {{new_url}}

 - Show the URL of a remote:
   git remote get-url {{remote_name}}

 - Remove a remote:
   git remote remove {{remote_name}}

 - Rename a remote:
   git remote rename {{old_name}} {{new_name}}

$ z demo-repo
$ git remote add origin https://github.com/darstib/demo-repo.git
$ git remote -v                                                 
origin  https://github.com/darstib/demo-repo.git (fetch)
origin  https://github.com/darstib/demo-repo.git (push)

$ git push -u origin master
Username for 'https://github.com': darstib
Password for 'https://darstib@github.com':
remote: Support for password authentication was removed on August 13, 2021.
remote: Please see https://docs.github.com/get-started/getting-started-with-git/about-remote-repositories#cloning-with-https-urls for information on currently recommended modes of authentication.
fatal: Authentication failed for 'https://github.com/darstib/demo-repo.git/'

$ git add -A
$ git commit -m "type: summary"
$ git push [origin master] # 指定 remote_name 和 branch_name