#########################################################
# My personal GIT tips
#########################################################

(1) Squash several commit into one (consolitation)
# Note:
#  Between HEAD and 3 is tilde sign
$ git rebase -i HEAD~3
# step 1: In pop-up editor (emacs), "pick" the earliest one and squash all the rest.
# step 2: In second pop-up editor, edit the commit message and save, exit.


(2) Pull the latest changes (sometime it is a fix/required) and put it under
# your working commit
$ git pull --rebase
# if there are any conflicts, you need edit the conflicted files manually. then 
$ git add <conflict and edited files>
$ git rebase --continue

# Note: Don't do git commit between "git add" and "git rebase --continue", 
  if you did, then you need git rebase --abort and come over.

# Another way (?) from Su Hui
$ git fetch
$ git rebase -i origin/nextgenv2
# -i ?, the following works:
$ git rebase origin/nextgenv2
# if there are any conflicts, you need edit the conflicted files manually. Sometimes
# need to diff against change in another repos or blame the conflict file to see the
# change.
$ git add <conflict and edited file>
$ git rebase --continue


(3) Create a branch from a older commit
# Create a branch from the top and specify the targeted remote branch
# Typically I need to create a branch for new code construction
$ git checkout -b <branch_name> <origin/nextgenv2>

# Typically I need to create a branch for performance test base (seat)
$ git checkout -b <branch_name> <commit>


(4) Restore the local top to <commit>
# Delete the current top commit 
$ git reset --hard <commit>

# Delete the current failed merge/modification
$ git reset --hard


(5) Diff a commit against its parent
$ git diff <commit>^!

# Diff HEAD agaist its parent
$ git diff HEAD^!

 
(6) Restore one file from previous commit and fix latest commit
$ git checkout <commit> <filename>
$ git commit --amend


(7) Merge a commit from master branch to another branch
$ git checkout <branch>
# use cherry pick. Please make sure the <branch> is clean and latest 
$ git fetch https://chromium.googlesource.com/webm/libvpx refs/changes/18/336818/3 && git cherry-pick FETCH_HEAD
# if there is no conflict, it automatically merge (if successfull) with local. And 
# the commit appears if do "git log"
# if there is conflict, need to merge manually and $ git commit -a --amend (i guess)


(8) Cherry pick
# This way we add an extra line (reference to the picked commit)
$ git cherry-pick -x <commit hash>


(9) Sandbox push
First ask Admin to create a sandbox (remote branch) for you.
# Work in local from git init, git commit ....
# Initial push:
# Here we use "head" instead of "for", "for" is for review board. Please note:
# we use -f
$ git push -f https://chromium-review.googlesource.com/webm/libvpx HEAD:refs/heads/sandbox/luoyi@google.com/convolve
$ git checkout -b sandbox/luoyi@google.com/convolve

# check it out:
$ git checkout -b codestore origin/sandbox/luoyi@google.com/convolve

# Push
# Run git push, then the error message would show you two ways. The first way works. See following:
$ git push origin HEAD:sandbox/luoyi@google.com/convolve

(10) Revert a change
$ git checkout <commit hash> <filename>
Revert a file at <commit hash> to index

(11) Diff current staged file (ready to commit) against a previous commit version
$ git diff --cached <commit hash> <path/file>

(12) Setup a branch for continuing work
# On a branch named: branch_name1,
$ git checkout -b <branch_name2>
$ git branch -u origin/nextgenv2
# latest commit may not be merged yet. So after local check-in, can we do
  cherry-pick later from branch_name2 to branch_name1?

(13) Generate and Apply a patch
$ git diff --no-ext-diff > my.diff
$ git apply my.diff

(14) git log --pretty=format:"%h %an %cd %s" --date=short
     git log --pretty=fuller

(15) git rebase -i origin/master
     Remove current unwanted base patch
     Pull in latest patches
     
########################################################
# Trivial tips now
########################################################
(1) Push for a review
$ git push https://chromium-review.googlesource.com/webm/libvpx HEAD:refs/for/nextgenv2
or
$ review_push.sh

(2) Show git remote repo
$ git remote show origin

(3) Check codebase's tag information
$ git tag
$ git rev-list -n1 v0.1.0