“git format-patch”和“git diff”有什么区别？

What is the difference between 'git format-patch and 'git diff'?

提问by Rafid

I don't see a difference between the output of 'git format-patch' and 'git diff', is there any? And won't I be able to use 'git diff' to produce a patch and then apply it using git apply?

我看不出 'git format-patch' 和 'git diff' 的输出有什么区别，有什么区别吗？我不能使用“git diff”来生成补丁，然后使用 git apply 应用它吗？

My problem is that I have changes added to the index, but apparently git format-patch only accepts commits, so if I can use the output of diff, then I can use this command to produce a patch for the changes in the index:

我的问题是我在索引中添加了更改，但显然 git format-patch 只接受提交，所以如果我可以使用 diff 的输出，那么我可以使用此命令为索引中的更改生成补丁：

git diff --cached > index.patch

回答by Sylvain Defresne

A patch created with git format-patchwill also include some meta-information about the commit (committer, date, commit message, ...) and will contains diff of binary data. Everything will be formatted as a mail, so that it can be easily sent. The person that receive it can then recreate the corresponding commit with git amand all meta-data will be intact. It can also be applied with git applyas it is a super-set of a simple diff.

创建的补丁git format-patch还将包含有关提交的一些元信息（提交者、日期、提交消息等），并将包含二进制数据的差异。一切都将格式化为邮件，以便可以轻松发送。收到它的人然后可以重新创建相应的提交，git am并且所有元数据都将完好无损。它也可以应用，git apply因为它是简单差异的超集。

A patch crated with git diffwill be a simple diff with context (think diff -u). It can also be applied with git applybut the meta-data will not be recreated (as they are not present).

打包的补丁git diff将是一个简单的上下文差异（想想diff -u）。它也可以应用，git apply但不会重新创建元数据（因为它们不存在）。

In summary, git format-patchis useful to transmit a commit, while git diffis useful to get a diff between two trees.

总之，git format-patch对于传输提交git diff很有用，而对于获取两棵树之间的差异很有用。

回答by Abizern

From the manuals git-format-patchprepares patches suitable for email submission, while git-diffshows changes.

从手册中git-format-patch准备适合电子邮件提交的补丁，而git-diff显示更改。

They are two different things and have different purposes, they just happen to output a patch format. But git-format-patchadds data about a commit (date, author, commit message) and bundles it up into a format that is suitable for sending as a Unix mail message (although these are just files, so they can be sent to other methods and still applied by git-am).

它们是两种不同的东西，具有不同的用途，它们只是碰巧输出一种补丁格式。但是git-format-patch添加有关提交的数据（日期，作者，提交消息）并将其捆绑成适合作为 Unix 邮件消息发送的格式（尽管这些只是文件，因此它们可以发送到其他方法并仍然由git-am）。

Also git-format-patchgenerates a patch file for each commit in the range that you specify. These changes will be added as commits to your repository with git-am.

还会git-format-patch为您指定范围内的每个提交生成一个补丁文件。这些更改将作为提交添加到您的存储库中git-am。

git-diffjust shows the diff between the two states you ask for, and can be used to create a patch file. But this is just a normal patch file and applying the patch will just change the state of the working directory.

git-diff仅显示您要求的两种状态之间的差异，并可用于创建补丁文件。但这只是一个普通的补丁文件，应用补丁只会改变工作目录的状态。

And yes, you can create a patch for your index that way.

是的，您可以通过这种方式为索引创建补丁。

回答by K. Symbol

The patch file can be generated with the git diffcommand, but comparing with the patch generated by the git format-patchcommand, the major differences are:

可以使用git diff命令生成补丁文件，但与git format-patch命令生成的补丁相比，主要区别在于：

1. No metadata about a commit (such as date, author, commit message, etc.) ;
2. No statistics about the diff (diffstat, such as x files changed, y insertions(+), z deletions(-));
3. No binary diffs, only textual diffs.

1. 没有关于提交的元数据（例如日期、作者、提交消息等）；
2. 没有关于diff的统计（diffstat，比如x个文件改变了，y个插入（+），z个删除（-））；
3. 没有二进制差异，只有文本差异。

To generate the patch file for all changed files (in the index or the working directory):

要为所有更改的文件（在索引或工作目录中）生成补丁文件：

git diff HEAD --binary > my.patch
# git diff + git diff --cached/staged == git diff HEAD

To apply the generated patch file:

应用生成的补丁文件：

# restore the changed files firstly
git restore --staged .
git restore .

# apply the patch to redo the changes 
git apply my.patch
# or
patch -p1 < my.patch