如果这是一个脚本，你可以使用:

git fetch
$(git rev-parse HEAD) == $(git rev-parse @{u})

(注意:与之前的答案相比，这个答案的好处是您不需要单独的命令来获取当前的分支名称。“HEAD”和“@{u}”(当前分支的上游)负责处理它。详见“git rev-parse——help”。)

我基于@jberger的评论来解决这个问题。

if git checkout master &&
    git fetch origin master &&
    [ `git rev-list HEAD...origin/master --count` != 0 ] &&
    git merge origin/master
then
    echo 'Updated!'
else
    echo 'Not updated.'
fi

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.

如果你运行这个脚本，它将测试当前分支是否需要git拉:

#!/bin/bash

git fetch -v --dry-run 2>&1 |
    grep -qE "\[up\s+to\s+date\]\s+$(
        git branch 2>/dev/null |
           sed -n '/^\*/s/^\* //p' |
                sed -r 's:(\+|\*|\$):\\\1:g'
    )\s+" || {
        echo >&2 "Current branch need a 'git pull' before commit"
        exit 1
}

将它作为Git钩子预提交来避免非常方便

Merge branch 'foobar' of url:/path/to/git/foobar into foobar

当你承诺之前拉。

要将此代码用作钩子，只需复制/粘贴脚本即可

.git/hooks/pre-commit

and

chmod +x .git/hooks/pre-commit

在阅读了许多答案和多个帖子，并花了半天时间尝试各种排列之后，这就是我想出的。

如果你在Windows上，你可以使用Git for Windows提供的Git Bash在Windows中运行这个脚本(安装或移植)。

这个脚本需要参数

- local path e.g. /d/source/project1
- Git URL e.g. https://username@bitbucket.org/username/project1.git
- password

if a password should not be entered on the command line in plain text,
then modify the script to check if GITPASS is empty; do not
replace and let Git prompt for a password

脚本将会

- Find the current branch
- Get the SHA1 of the remote on that branch
- Get the SHA1 of the local on that branch
- Compare them.

如果脚本打印了更改，那么您可以继续获取或拉取。脚本可能效率不高，但它为我完成了工作。

更新- 2015-10-30:stderr to dev null，防止将URL和密码打印到控制台。

#!/bin/bash

# Shell script to check if a Git pull is required.

LOCALPATH=$1
GITURL=$2
GITPASS=$3

cd $LOCALPATH
BRANCH="$(git rev-parse --abbrev-ref HEAD)"

echo
echo git url = $GITURL
echo branch = $BRANCH

# Bash replace - replace @ with :password@ in the GIT URL
GITURL2="${GITURL/@/:$GITPASS@}"
FOO="$(git ls-remote $GITURL2 -h $BRANCH 2> /dev/null)"
if [ "$?" != "0" ]; then
  echo cannot get remote status
  exit 2
fi
FOO_ARRAY=($FOO)
BAR=${FOO_ARRAY[0]}
echo [$BAR]

LOCALBAR="$(git rev-parse HEAD)"
echo [$LOCALBAR]
echo

if [ "$BAR" == "$LOCALBAR" ]; then
  #read -t10 -n1 -r -p 'Press any key in the next ten seconds...' key
  echo No changes
  exit 0
else
  #read -t10 -n1 -r -p 'Press any key in the next ten seconds...' key
  #echo pressed $key
  echo There are changes between local and remote repositories.
  exit 1
fi

下面的脚本运行良好。

changed=0
git remote update && git status -uno | grep -q 'Your branch is behind' && changed=1
if [ $changed = 1 ]; then
    git pull
    echo "Updated successfully";
else
    echo "Up-to-date"
fi