gistfile1.txt

# returns back what was changed after gitting pull locally. 
git diff HEAD^^ HEAD nmae/of/thefile.rb

FYI , 
# this will show what was last added your local "showing newly added changes"
git diff --color HEAD^ HEAD

# this will do the reverse .. it will show the commit prior to pulling from the remote. 
git diff --color HEAD HEAD^


========================================================

gets the diff between between branch and master , and you can pass the name of the file as an arg.
[za]$ git diff --color-words master..somebranch^^ somescripts.rb 
[za]$ git diff --color master^..origin/master # compare master before pulling from origin/master
OR
]$ git diff --color master..origin/master^

# compare newly created branch with the master in which the branch was created from . 
 git diff  name_of_branch remotes/origin/HEAD

========================================================

⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓

git log "$@" --pretty=format:'%T %h %s'

2108234324343432432432432423432423432434 4324349 Addmyapp first comment
2erwrdd3c0e6ea4aa6c37e835e d13d936 Add some comment
d15e56ewerwd620eb3cf3a6fdf12b89d f6af877 Add some morestuff
1578b58868d3af476ea6b00e4ea5c473a5c52c3b cc23989 changed the engine oil
erweeewrerererwererwer2da096cef340a48862c c04f506 not yet done.


==============================================================================

git push -all -u

pushes master /branches at once. 
==============================================================================
had this 

-sh-4.1$ git branch
  master
* somebranch

and wasgetting 

sh-4.1$ git push

 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'git@github,,,,,'

fixed it like this…. 

git checkout master
git pull
(merge happens in background)
git push


then 

sh-4.1$ git checkout branchname
Switched to branch 'branchname
-sh-4.1$ git push
Counting objects: 3, done.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 633 bytes, done.
Total 3 (delta 0), reused 0 (delta 0)
remote: => Syncing Git... [OK]
   da8sds1..c11sd  master -> master
==============================================================================

rename a branch locally and remotetly . 


git branch -m old_branch new_branch         # Rename branch locally    
git push origin :old_branch                 # Delete the old branch    
git push --set-upstream origin new_branch   # Push the new branch, set local branch to track the new remote
==============================================================================

# pull from a branch.
git pull origin other-branch

git log --author="<zeyadatef@gmail.com" --oneline --shortstat

==============================================================================
git commit --amend -m "New commit message"


===============================================================================
reverting to previous head : 

git reflog
 git reset --hard sdfdd0ea5   or HEAD^ or HEAD@{2} 


===============================================================================
# after git pull , take the commit hash and compare it woth local head^ to see the difference between the two.
git difftool HEAD^  062f72413335508beea563f53be17156b5bd9ecc

==========================================================================
#Another way to compare the current master with the upstream master, is by doing a git fetch and then compare the 
# fetched_head before mergeing the changes with the current head. 

git fetch
git log -p HEAD..FETCH_HEAD
 or 
 git diff --color  master origin/master

===============================================================================
fatal: git checkout: updating paths is incompatible with switching branches.
Did you intend to checkout 'origin/somebranch' which can not be resolved as commit?


solve it : 

I believe this occurs when you are trying to checkout a remote branch that your local git repo is not aware of yet. Try:

git remote show origin
If the remote branch you want to checkout is under "New remote branches" and not "Tracked remote branches" then you need to fetch them first:

git remote update
git fetch
Now it should work:


# create local branch and pull remote into it ....
#Warning .. doing just git pull origin branc_name will cause the branch to merge with master.
git checkout -b local-name origin/remote-name
~
~
~
[za$ git remote show origin
* remote origin


[za]$ git branch -vv
===========================OBJECTS====================================
A single tree object contains one or more tree entries, each of which contains a SHA-1 pointer to a blob or subtree with its associated mode, type, and filename. For example, the most recent tree in a project may look something like this:


git cat-file -p master^{tree}

#use the army swiss knife git cat-file -p fdsfdf909dfs9dfsd9f0sdf to decipher the checksum "SHA"
 git cat-file -p 



-------------------------------------

Wanted to add two remotes so that i can push to / pull from ,... the way to do is like this 

# if the remote is not created yet , do 
za:vi_dir za$ git remote add  origin git@gitlab.com:z-a/vi_dir.git 
za:vi_dir za$ git remote -v
origin	git@gitlab.com:z-a/vi_dir.git (fetch)
origin	git@gitlab.com:z-a/vi_dir.git (push)

# if it s created and you just want to link it , then do : 

this will only allow you to push:
za]$ git remote set-url --add --push origin git@git.org:apps/some-repo.git


#without --push  it will be set to push and pull.
za]$ git remote set-url --add origin git@git.org:apps/some-repo.git


and the best of all is to run the following command and add/delete remotes as desired.

za]$ git config -e

# one of the coolest commands ever... eg . git ls-files -s OR -c OR -d... check th manual page
za]$ git help ls-files
-------------------------------------
reverting a push can be easl=ily done if you are the last person who pushed . 

https://www.kernel.org/pub/software/scm/git/docs/user-manual.html#fixing-mistakes


za] git reflog 
bf2a94r HEAD@{0}: blah blah
bf2a94r HEAD@{1}: The commit I want to go back to .


>> got the commit number  , now reet head to the head{1}
]$ git reset --hard HEAD@{1}
>>another reflog will tell what was changed . 
za] git reflog 
bf2awef HEAD@{0}: HEAD@{1}: updating HEAD

>> git diff with two ".."
git diff  231062d..bf2a95e 


-------------------
e]$ git var -l

SOB=$(git var GIT_AUTHOR_IDENT | sed -n 's/^\(.*>\).*$/ \1/p') ; echo $SOB


# search entire reflist for a string.
za$ git rev-list --all | (     while read revision; do         git grep -F 'liberty' $revision;     done; )

--------------------
#check out remote branch without having to checkout from master "in case you master is bad"

git branch --set-upstream branchname origin/branchname 


=======================
# On branch master
# Your branch is ahead of 'origin/master' by 30 commits.

solved with 

git pull origin     #but this will bring down everything from the upstream.


in a second time, i solved with 

git reset HEAD^ --hard

#
 git checkout somebranch
 error: Untracked working tree file 'somefile.rb' would be overwritten by merge.
 
 Fixed it by doing . 
 
 git fetch --all
 
 -sh-4.1$ git reset --hard origin/somebranch
    Checking out files: 100% (24/24), done.
    
    
    git log --all --oneline --graph --decorate