git, repo advance skills

git

• git checkout -b branchname startpoint :

make a branch named "branchname" based on the startpoint commit;以startpoint提交点为基点创建一个名为branchname的branch

• git rev-parse HEAD(git symboli-ref HEAD) :

show the commit hash revision value(the commit symbolic value) of HEAD pointer；

• git rebase --onto master server client :

check out the client branch, figure out the patches from the common ancestor of the client and server branches, and then replay them onto master; 找出从client分支和server分支的共同祖先之后到client分支的修改,在master分支上重演一遍; Normally, after this command is executed, HEAD would be detached. git symbolic-ref HEAD fails with fatal: ref HEAD is not a symbolic ref; git rev-parse HEAD yields a hash code (17a02998078923f2d62811326d130de991d1a923). To recover from this situation, try commands: git branch temp; git checkout temp; git branch -f master temp; git checkout master. 一般的, 在这条命令执行后, HEAD引用将会和master分离. git symbolic-ref HEAD会报错: HEAD引用不是一个标号引用. git rev-parse HEAD会报告一个hash code而不是一个符号. 如果要恢复的话, 可以尝试命令: git branch temp; git checkout temp; git branch -f master temp; git checkout master.

• git log --oneline --decorate --graph --all :

show your project history in graph;以图形方式显示你项目的历史

• git tag -a v1.2 9fceb02 :

create a tag v1.2 connecting to 9fceb02 reference; 以引用9fce602为基础创名为v1.2的tag

• git checkout -b [branchname] [tagname] :

create a branch named "branchname" connecting to tag "tagname"; 以名为"tagname"的tag为基础创建branch(名为"branchName")

• git ls-files --modified | xargs -i git checkout {} :

restore modified files from repository; 将已经修改的文件恢从仓库出恢复.

• tag show-ref --tags :

  how to show tags with their reference hash codes; 列出所有tag和它们的引用

• git ls-remote --tags :

show remote tags and their reference codes; 列出所有远端的tag和它们的引用

repo

• switch to an android branch without downloading files from server again;can I change my current branches from gingerbread to ICS and possibly back; fetch this branch based on the downloaded files: 怎样基于已经下载的git仓库切换Android版本

fetch all tags from server
repo forall -c git fetch aosp --tags
checkout john5.1.1_r14_api22 branch based on android-5.1.1_r14 branch
repo forall -c git checkout -b john5.1.1_r14_api22 android-5.1.1_r14

useful links

• AOSP codenames, Tags, and Build Numbers

27 Mar 2016