### Git Diff

    git diff                 // Look diff from previous commited version

    git diff > temp.patch    // Output diff to patch file
    git apply temp.patch     // Apply patch 'pk_xxx'

    git reset --hard 6a137   // Force reset to version '6a137' will lost new commit
    git format-patch HEAD^^^ // Patch to nth(^) previos version from HEAD, output multiple files

    git diff --u=10          // Show 10 lines context of diff

### Git Branch 

    git checkout .				// Discard local changes of all files
    git checkout <somefile>		// Discard local changes of some file
    
	git branch -av    // detail branch info
	
	git branch -u origin/<remote-branch-name> // setup tracking remote branch
	
	// Stash
	git stash save "work in progress for foo feature"
	git stash list
	git stash apply stash@{1}
	
	// List which branch (remote & local) contains some commit
	git branch -a --contains <commit_id>
	
	// Merge multiple commits to one commit
	// (ex: ABCDE), you want to ABE'(E'=CDE)
	git rebase -i HEAD~2	// rebase to C
	s e97a17b E
	s asd314f D
	p asd314f C
	
	// 如何分辨 local branch 追蹤哪一個 remote branch
	git remote show origin
	
	// Create remote branch
	git checkout -b your_branch
	git push -u origin your_branch
	
	// Delete remote branch
	git push origin :your_branch
	
	// 遠端分支被刪除要用 -p 更新 branch 資訊
	git fetch -p

### Git Log 

	git log --pretty=short           // 簡短的log
	git log --oneline                // 超短的log
	git log --author="Jon"           // Show Jon's commits
	git log /drivers/video           // 只看drivers/video資料夾下更動的log
	git log ./                       // 只看當前資料夾下更動的log

	git blame sha1_file.c            // 查看sha1_file.c 的修改
	git blame -L 160,+10 sha1_file.c // 查看sha1_file.c 從第160行開始往下10行，是誰修改的

	git log --grep=word              // 搜尋 commit message 包含 'word' 的 commit
	git log -Sword                   // 搜尋 commit 修改內容包含 'word' 的 commit

	git log -5 --name-only           // 查最近 5 筆 commit 有修改哪些檔案

	// 搜尋哪一筆 commit 在 SurfaceFlinger.cpp 中曾經修改過 surface_flinger_cblk_t 這個關鍵字
	git log -S"surface_flinger_cblk_t" -p services/surfaceflinger/SurfaceFlinger.cpp
	
	// 樹狀圖看log merge path
	git log --graph --pretty=format:'%Cred%h%Creset:%s  %Cgreen(%cr)%Creset %an' --abbrev-commit --date=relative

### Git Patch 

	git format-patch -1 7ef30fa // 取出單一commit為patch

	git am                      // apply format-patch patch
	git apply                   // apply diff > patch

	git apply --reject          // 會把可以上的部份上去，衝突部份他會寫到 xxx.c.rej 檔案中

	git reset                   // 把 changes to be commited 的部份拉到 changes but not commit
	git ch .                    // 把 changes but not commit 變成 no changes
	
	// Single file checkout
	git checkout v1.2.3 -- filename         // tag v1.2.3
	git checkout stable -- filename         // stable branch
	git checkout origin/master -- filename  // upstream master
	git checkout HEAD -- filename           // the version from the most recent commit
	git checkout HEAD^ -- filename          // the version before the most recent commit
	
	// git revert
	git revert 2cded15f64b2eb6f8acc   // revert a previous commit, and the revert action will become a new commit
	
	// git bisect
	git bisect start
	git bisect bad 2ac4169f24e91e10d683cbf4676d
	git bisect good a49b61dbb440fa48f78adece5e5980
	
	// cherry-pick partial commit
	git cherry-pick -n <commit>   # get your patch, but don't commit (-n = --no-commit)
	git reset                     # unstage the changes from the cherry-picked commit
	git add -p                    # make all your choices (add the changes you do want)
	git commit                    # make the commit!
	
	// Keep commit and remove some content
	git checkout -b test
	git reset --hard HEAD^
	git cherry-pick -n master
	git reset .
	git add -p
	git diff master > patch
	git checkout -f master
	git apply patch
	git cm --amend