如何检查远程存储库是否已更改,是否需要进行拉取?

现在我使用这个简单的脚本:

git pull --dry-run | grep -q -v 'Already up-to-date.' && changed=1

但它相当重。

有没有更好的办法?理想的解决方案是检查所有远程分支,并返回已更改分支的名称以及每个分支中新提交的数量。


当前回答

对于那些在这个问题上寻找答案的windows用户,我已经将部分答案修改为powershell脚本。根据需要进行调整,保存到.ps1文件,并根据需要或计划运行。

cd C:\<path to repo>
git remote update                           #update remote
$msg = git remote show origin               #capture status
$update = $msg -like '*local out of date*'
if($update.length -gt 0){                   #if local needs update
    Write-Host ('needs update')
    git pull
    git reset --hard origin/master
    Write-Host ('local updated')
} else {
    Write-Host ('no update needed')
}

其他回答

下面是一个Bash一行代码,比较了当前分支的HEAD提交哈希和它的远程上游分支,不需要大量的git获取或git拉取——需要干运行操作:

[ $(git rev-parse HEAD) = $(git ls-remote $(git rev-parse --abbrev-ref @{u} | \
sed 's/\// /g') | cut -f1) ] && echo up to date || echo not up to date

以下是这条有点密集的线是如何被分解的:

Commands are grouped and nested using $(x) Bash command-substitution syntax. git rev-parse --abbrev-ref @{u} returns an abbreviated upstream ref (e.g. origin/master), which is then converted into space-separated fields by the piped sed command, e.g. origin master. This string is fed into git ls-remote which returns the head commit of the remote branch. This command will communicate with the remote repository. The piped cut command extracts just the first field (the commit hash), removing the tab-separated reference string. git rev-parse HEAD returns the local commit hash. The Bash syntax [ a = b ] && x || y completes the one-liner: this is a Bash string-comparison = within a test construct [ test ], followed by and-list and or-list constructs && true || false.

我使用了一个基于Stephen Haberman回答的脚本版本:

if [ -n "$1" ]; then
    gitbin="git -C $1"
else
    gitbin="git"
fi

# Fetches from all the remotes, although --all can be replaced with origin
$gitbin fetch --all
if [ $($gitbin rev-parse HEAD) != $($gitbin rev-parse @{u}) ]; then
    $gitbin rebase @{u} --preserve-merges
fi

假设此脚本名为Git -fetch-and-rebase,可以使用本地Git存储库的可选参数目录名来调用它,以执行操作。如果调用脚本时不带参数,则假定当前目录是Git存储库的一部分。

例子:

# Operates on /abc/def/my-git-repo-dir
git-fetch-and-rebase /abc/def/my-git-repo-dir

# Operates on the Git repository which the current working directory is part of
git-fetch-and-rebase

这里也有。

所有这些复杂的建议,而解决方案却如此简单:

#!/bin/bash

BRANCH="<your branch name>"
LAST_UPDATE=`git show --no-notes --format=format:"%H" $BRANCH | head -n 1`
LAST_COMMIT=`git show --no-notes --format=format:"%H" origin/$BRANCH | head -n 1`

git remote update
if [ $LAST_COMMIT != $LAST_UPDATE ]; then
        echo "Updating your branch $BRANCH"
        git pull --no-edit
else
        echo "No updates available"
fi

对于那些在这个问题上寻找答案的windows用户,我已经将部分答案修改为powershell脚本。根据需要进行调整,保存到.ps1文件,并根据需要或计划运行。

cd C:\<path to repo>
git remote update                           #update remote
$msg = git remote show origin               #capture status
$update = $msg -like '*local out of date*'
if($update.length -gt 0){                   #if local needs update
    Write-Host ('needs update')
    git pull
    git reset --hard origin/master
    Write-Host ('local updated')
} else {
    Write-Host ('no update needed')
}

命令

git ls-remote origin -h refs/heads/master

将列出远程上的当前头—您可以将其与以前的值进行比较,或者查看您的本地回购中是否有SHA。