git diff

Tips：HEAD commit版本 Index staged版本

a、查看尚未暂存的文件更新了哪些部分，不加参数直接输入

    git diff

此命令比较的是工作目录(Working tree)和暂存区域快照(index)之间的差异
也就是修改之后还没有暂存起来的变化内容。

b、查看已经暂存起来的文件(staged)和上次提交时的快照之间(HEAD)的差异

    git diff --cached    git diff --staged

显示的是下一次commit时会提交到HEAD的内容(不带-a情况下)

c、显示工作版本(Working tree)和HEAD的差别

   git diff HEAD

d、直接将两个分支上最新的提交做diff

    git diff topic master 或 git diff topic..master

e、输出自topic和master分别开发以来，master分支上的changed。

  git diff topic...master

Changes that occurred on the master branch since when the topic branch was started off it

f、查看简单的diff结果，可以加上–stat参数

    git diff --stat

g、查看当前目录和另外一个分支的差别

    git diff test

显示当前目录和另一个叫’test’分支的差别

   git diff HEAD -- ./lib

显示当前目录下的lib目录和上次提交之间的差别（更准确的说是在当前分支下）

h、比较上次提交commit和上上次提交

    git diff HEAD^ HEAD

i、比较两个历史版本之间的差异

    git diff SHA1 SHA2