标签：git -- relea dev Git file checkout

Git Checkout

名称

git-Checkout - 切换分支或恢复工作树文件

语法

git checkout [-q] [-f] [-m] [<branch>]
git checkout [-q] [-f] [-m] --detach [<branch>]
git checkout [-q] [-f] [-m] [--detach] <commit>
git checkout [-q] [-f] [-m] [[-b|-B|--orphan] <new_branch>] [<start_point>]
git checkout [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] [--] <pathspec>…
git checkout [-f|--ours|--theirs|-m|--conflict=<style>] [<tree-ish>] --pathspec-from-file=<file> [--pathspec-file-nul]
git checkout (-p|--patch) [<tree-ish>] [--] [<pathspec>]

更新工作树中的文件以匹配索引或指定树中的版本。如果没有给出路径规范 -- pathspec，git checkout也会更新HEAD以将指定的分支设置为当前分支。

使用

## 项目当前分支状态
$ git branch -a -vv 
  dev                  26e602f [origin/dev] dev commit
* main                 9df539e [origin/main] main file
  relea                c76aaf9 [origin/relea] rele
  remotes/origin/HEAD  -> origin/main
  remotes/origin/dev   26e602f dev commit
  remotes/origin/main  9df539e main file
  remotes/origin/relea c76aaf9 rele
  
##　删除分支dev relea 
$ git branch -d dev relea 
warning: deleting branch 'dev' that has been merged to
         'refs/remotes/origin/dev', but not yet merged to HEAD.
warning: deleting branch 'relea' that has been merged to
         'refs/remotes/origin/relea', but not yet merged to HEAD.
Deleted branch dev (was 26e602f).  
Deleted branch relea (was c76aaf9).

git checkout [<branch>]

为了准备在<分支>上工作，通过更新工作树中的索引和文件，并将HEAD指向分支来切换到它。保留对工作树中文件的本地修改，以便它们可以提交到<分支>。

如果未找到<branch>，但在一个具有匹配名称的远程（将其称为<远程>）中确实存在跟踪分支，并且未指定--no-guess，则将其视为等效于 git checkout -b <branch> --track <remote>/<branch>

## 当一个分支在本地和远程都找不到时会报错
xuyuansheng@XUYUANSHENG MINGW64 /d/VSCode/testgit (main)
$ git checkout abc
error: pathspec 'abc' did not match any file(s) known to git
## 如果本地没有该分支，远程有时就会从远程拉取分支 
xuyuansheng@XUYUANSHENG MINGW64 /d/VSCode/testgit (main)
$ git checkout --no-guess  dev  
error: pathspec 'dev' did not match any file(s) known to git
$ git checkout dev 
Switched to a new branch 'dev'
Branch 'dev' set up to track remote branch 'dev' from 'origin'.
## 当着分支状态
$ git log --pretty=oneline --graph main dev 
* 9df539ee86586d32d4349aa19e235941926cefec (origin/main, origin/HEAD, main) main file
| * 26e602f538ab6a74ac985853690136e064cbe172 (HEAD -> dev, origin/dev) dev commit    
| * 1d40930975eaeef50830c457bdcd7811db6ef173 first main commit
|/
* a94823afd688061ad02285591fb36a7dbeb520dd Initial commit

您可以省略<branch>，在这种情况下，命令退化为“签出当前分支”，这是一种美化的无操作，具有相当昂贵的副作用，仅显示当前分支的跟踪信息（如果存在）。

$ git checkout  --track origin/relea
Switched to a new branch 'relea'
Branch 'relea' set up to track remote branch 'relea' from 'origin'.

-b|-B 创建新分支

git checkout -b|-B <new_branch> []

指定-b会创建一个新分支，就像调用git-branch(1)然后签出一样。在这种情况下，您可以使用--trackor--no-track选项，它将被传递给git branch。为方便起见， --track没有-b意味着创建分支；见下面的描述--track。

如果-B给出，<new_branch>则在不存在时创建；否则，它被重置。

## 查看当前分支状态和提交log
$ git branch -vv 
  dev   26e602f [origin/dev] dev commit
  main  9df539e [origin/main] main file
* relea c76aaf9 [origin/relea] rele
$ git log --pretty=oneline 
c76aaf9fef36c80c2a315a2c4e859f1582270ec3 (HEAD -> relea, origin/relea) rele
26e602f538ab6a74ac985853690136e064cbe172 (origin/dev, dev) dev commit
1d40930975eaeef50830c457bdcd7811db6ef173 first main commit
a94823afd688061ad02285591fb36a7dbeb520dd Initial commit

## -b  创建并切换到新分支
$ git checkout -b fromRelea 1d40930975eaeef50830c457bdcd7811db6ef173 
Switched to a new branch 'fromRelea'
$  git log --pretty=oneline 
1d40930975eaeef50830c457bdcd7811db6ef173 (HEAD -> fromRelea) first main commit
a94823afd688061ad02285591fb36a7dbeb520dd Initial commit
## 再来一次，失败了、因为分支已经存在
$ git checkout -b fromRelea 
fatal: A branch named 'fromRelea' already exists.
## 使用-B 强制签出，这里会重置已经存在的分支
$ git  checkout relea 
$ git checkout -B  fromRelea
Switched to and reset branch 'fromRelea'
$ git log --pretty=oneline
c76aaf9fef36c80c2a315a2c4e859f1582270ec3 (HEAD -> fromRelea, origin/relea, relea) rele
26e602f538ab6a74ac985853690136e064cbe172 (origin/dev, dev) dev commit
1d40930975eaeef50830c457bdcd7811db6ef173 first main commit
a94823afd688061ad02285591fb36a7dbeb520dd Initial commit

--detach 分离头指针

git checkout --detach [<branch>] / git checkout [--detach] <commit>

准备在之上工作<commit>，方法是HEAD在它上分离，并更新工作树中的索引和文件。保留对工作树中文件的本地修改，因此生成的工作树将是提交中记录的状态加上本地修改。当<commit>参数是分支名称时，该--detach选项可用于HEAD在分支的HEAD分离（git checkout <branch>将在不分离的情况下检查该分支HEAD）。在当前分支的HEAD省略<branch>分离HEAD。

$ git checkout dev 
$ cat .git/HEAD
ref: refs/heads/relea
## HEAD指向relea分支，相当于间接指向提交 c76aaf9
$ cat .git/refs/heads/relea
c76aaf9fef36c80c2a315a2c4e859f1582270ec3
$ git log --pretty=reference
c76aaf9 (rele, 2022-10-25)
26e602f (dev commit, 2022-10-25)
1d40930 (first main commit, 2022-10-25)
a94823a (Initial commit, 2022-10-25)
## --detach ，HEAD会直接指向特定的commit ，此时不在任何分支上
$ git checkout --detach dev 
HEAD is now at 26e602f dev commit
Your branch is up to date with 'origin/dev' 
$ git checkout --detach 26e602f 
HEAD is now at 26e602f dev commit
$  cat .git/HEAD
26e602f538ab6a74ac985853690136e064cbe172
## 此时会可以在当前commit上创建新分支

-- <pathspec> 限制受checkout 操作影响的路径

如果没有指定时pathspec，会更新HEAD以将指定的分支设置为当前分支或HEAD指定指定commit

语法： git checkout [<tree-ish>] [--] [<pathspec>... ]

<tree-ish> checkout的树（当给出路径时）。如果未指定，将使用索引(HEAD)。

$ git branch -vv 
  dev       26e602f [origin/dev] dev commit
  fromRelea c76aaf9 rele
  main      9df539e [origin/main] main file
* relea     95ef627 [origin/relea: ahead 1] commit dev file in relea
## 在当前分支(relea)修改文件dev 
$ echo 'edit file in relea' >> dev
$ git add dev 
$ echo 'edit one more time' >> dev
$ git status 
On branch relea
Your branch is ahead of 'origin/relea' by 1 commit.
  (use "git push" to publish your local commits)
Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
        modified:   dev
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
        modified:   dev
## 查看(索引)暂存区、工作树、Git库中dev文件内容
$ git ls-files --stage |grep  -E 'dev$'  |awk '{print$2}' |xargs git cat-file -p
dev file in relea
edit file in relea
## 查看Git库中文件内容(真难，有谁知道更好的办法请告诉我)
$ git cat-file -p  HEAD |grep tree |awk '{print$2}' |xargs git cat-file -p |grep  -E 'dev$' |awk '{print$3}' |xargs git cat-file -p 
dev file in relea
## 查看工作树中文件
$ cat dev
dev file in relea
edit file in relea
edit one more time
## checkout 签出dev文件内容
##  错误，提示你本地有未提交的修改，无法切换到dev，这时候dev被识别为了一个分支
$ git checkout  dev
error: Your local changes to the following files would be overwritten by checkout:
        dev
Please commit your changes or stash them before you switch branches.
Aborting
##使用-- <pathspec> 语法，成功签出，dev文件的内容变成了暂存区的内容，所以不指定tree-ish时默认是从暂存区签出
$ git checkout  -- dev
$ cat dev
dev file in relea
edit file in relea
##  指定tree-ish时，就会从指定的树(git中的树对象，不是工作树worktree)中签出文件内容
$ git checkout HEAD  -- dev
$ cat dev
dev file in relea

-p/--patch

git checkout (-p|--patch) [<tree-ish>] [--] [<pathspec>... ]

<tree-ish>在和工作树之间的差异中以交互方式选择大块(hunk ) 。然后将选择的块反向应用于工作树（如果<tree-ish>指定了，则为索引）。这意味着您可以使用它git checkout -p来选择性地丢弃当前工作树中的编辑。请参阅git-add(1)的“交互模式”部分以了解如何操作该--patch模式。请注意，此选项默认使用无覆盖模式（另请参阅 --overlay），目前不支持覆盖模式。

## 接上例 ,再次修改dev文件文件内容后
$ git status 
On branch relea
Your branch is ahead of 'origin/relea' by 1 commit.
  (use "git push" to publish your local commits)
Changes to be committed:
        modified:   dev
Changes not staged for commit:
        modified:   dev
## 以交互的模式签出指定文件
$ git checkout -p -- dev
diff --git a/dev b/dev
index 5753032..228d0b0 100644
--- a/dev
+++ b/dev
@@ -1,2 +1,3 @@
 dev file in relea
 edit file in relea
+edit dev noe more time agin
\ No newline at end of file
## 从工作树中丢弃这个大块头？？ y=yes,n=no,q=quit...,具体交互方式参阅git-add
(1/1) Discard this hunk from worktree [y,n,q,a,d,e,?]?
## 输入y后 ，工作树中修改的内容被回退到暂存区一样了
$ git diff  -- dev

## 指定<tree-ish>,这时会将tree-ish与工作树(worktree)对比
$ git checkout -p HEAD  -- dev
diff --git a/dev b/dev
index f3e3544..e0b2374 100644
--- a/dev
+++ b/dev
@@ -1 +1,3 @@
 dev file in relea
+edit file in relea
+asfdadasdasf
\ No newline at end of file
## 第一次输入了yes，但是提示错误，因为这个修改块(hunk)没有应用到(索引)暂存区中
(1/1) Discard this hunk from index and worktree [y,n,q,a,d,e,?]? y
error: patch failed: dev:1      
error: dev: patch does not apply
The selected hunks do not apply to the index!
Apply them to the worktree anyway? y
## 上面再次输入yes,工作树中dev文件内容变为了和HEAD中文件一样
$ cat  dev
dev file in relea
$ git diff  -- dev
diff --git a/dev b/dev
index 5753032..f3e3544 100644
--- a/dev
+++ b/dev
@@ -1,2 +1 @@
 dev file in relea
-edit file in relea

--ignore-other-worktrees 忽略其他工作树

git checkout当想要的 ref 已经被另一个工作树签出时拒绝。这个选项使它无论如何都要检查参考。换句话说，ref 可以被多个工作树保存

$ git reset --hard HEAD 
HEAD is now at 95ef627 commit dev file in relea
$ git branch -vv
  dev       26e602f [origin/dev] dev commit
  fromRelea c76aaf9 rele
  main      9df539e [origin/main] main file
* relea     95ef627 [origin/relea: ahead 1] commit dev file in relea
## 从dev分支新建一个工作树
$ git  worktree add ../wtree_dev   dev
Preparing worktree (checking out 'dev')
HEAD is now at 26e602f dev commi
## 切换到新的工作树目录并查看分支状态（去掉了无关的分支）
$ cd ../wtree_dev/ && git branch -v
* dev       26e602f dev commit
  wtree     95ef627 commit dev file in relea
user@NAME MINGW64 /d/VSCode/wtree_dev (dev)
## 切换回Git仓库，并签出到指定(dev)分支
$ cd ../testgit/
$ git checkout dev 
fatal: 'dev' is already checked out at 'D:/VSCode/wtree_dev'
## --ignore-other-worktrees  忽略其他工作树 
$ git checkout --ignore-other-worktrees dev 
Switched to branch 'dev'
Your branch is up to date with 'origin/dev'.

--overwrite-ignore 覆盖忽略的文件(默认)

--no-overwrite-ignore

切换分支时静默覆盖忽略的文件。这是默认行为。--no-overwrite-ignore当新分支包含被忽略的文件时，用于中止操作。

$ git checkout relea
## 添加.gitignore文件(内容为 *.sh)，并提交后，新建一个ab.sh文件
$ echo 'sadfa' >  ab.sh
## 没有看懂，后续再看

--overlay /--no-overlay

在默认覆盖模式下，git checkout从不从索引或工作树中删除文件。指定--no-overlay时，将删除出现在索引和工作树中但不在其中的<tree-ish>文件，以使它们<tree-ish>完全匹配。

## 没有看懂，后续再看

标签：git,--,relea,dev,Git,file,checkout
From： https://www.cnblogs.com/xysgo/p/16834291.html

Git命令列表--git-checkout