First create the project in the git repository. Then copy the url. (possibly from https://git-scm.com/book/en/v2/Git-on-the-Server-Setting-Up-the-Server and https://git-scm.com/docs/git-shell)

This is a good method of limiting git to a non-interactive shell. Copy keys to the git user authorized_keys2 file in /l/git/.ssh on lycoming.

On the client:
<file>
git init testapp
cd testapp/
git config --global user.name "Stephen R Edwards"
git config --global user.email "steve.edwards@vt.edu"
touch README.md
git add README.md 
git add .
git commit -m 'First commit'
git remote add origin git@git.it.vt.edu:stedwar1/testapp.git
git push -u origin master
</file>

On git host server, initialize the repo:
<file>
git init --bare stedwar1/testapp
chown -R git:git stedwar1/
</file>

On the client:
<file>
git remote add origin ssh://git@lycoming.aoe.vt.edu:32722/l/git/stedwar1/testapp
git push -u origin master
</file>

====== markdown ======
Headlines
  ##
Blockquote
  >
Blockquote in a blockquote
  >>
Lists
  +
  or -
4 spaces for code indent

back tics for code inline
  test `code` inline
tab

Use delimited back tics to render a back quote
  test \'code\'
HTML
  <span class="special">

====== clone with all branches ======
  git clone --bare https://github.com/planetoftheweb/angular.git .git
  git config --bool core.bare false
  git reset --hard
  git branch
  git status
  git stash && git checkout 01_03
====== git essentials (lynda.com) ======
===== Configuration =====

  * System

  git config --system
  /etc/gitconfig
  Program Files\Git\etc\gitconfig

  * User

  git config --global
  ~/.gitconfig
  $HOME\.gitconfig
  git config --global user.name "Steve Edwards"
  git config --global user.email "steve.edwards@vt.edu"
  git config --list
  git config user.name
  git config user.email
  cd ~
  ls -la
  cat .gitconfig
  git config --global core.editor "mate -wl1" #(wait on line one)
  git config --global color.ui true
  cat .gitconfig
  
  git config --global core.excludesfile ~/.gitignore_global

  * Project

  git config
  my_project/.git/config

===== git-completion =====
  $ curl -OL https://github.com/git/git/raw/master/contrib/completion/git-completion.bash
  $ mv ~/git-completion.bash ~/.git-completion
  $ cat >> .bash_profile
  
  if [ -f ~/.git-completion.bash ]; then
    source ~/.git-completion.bash
  fi
  ^d
===== git help =====
  git help
  git help log
  
  man git-log

http://www.kernel.org/pub/software/scm/git/docs

====== 3. Getting Started ======

===== git initialize project =====
First create a new folder then cd into that folder
  cd ~/Documents
  mkdir first_git_project
  cd !$
  git init
creates the ./.git folder that tracks all the changes
  ls -la .git
Only the //config// file should be edited, but even git commands can edit this file.

git keeps all changes here, unlike svn that creates an svn file(?) in every directory.

Delete the .git and the changes are no longer being tracked.
===== git tracking changes =====
create a file, first_file.txt, in the project directory
  touch first_file.txt
  git add .
  git commit -m "Initial commit"

  * make changes
  * add the changes
  * commit changes to the repository with a message
===== writing commit messages =====
  * short single-line summary (less than 50 characters)
  * optionally followed by a blank line and a more complete descrtiption
  * keep each line to less than 72 charactes
  * write commit messages in the present tense, not past tense
    * "fix bug" or "fixes bug", not "fixed bug"
  * bullet points are usually asterisks or hyphens
  * can add "ticket tracking numbers" from bugs or support requests
  * can develop shorthand for your organization
    * "[css,js]"
    * "bugfix: "
    * "#38405 - "
  * Be clear and descriptive
    * Bad: "Fix typo"
    * Good: "Add missing > in project section of HTML"
    * Bad: "Update login code"
    * Good: "Change user authentication to use Blowfish
    * Bad: "Updates member report, we should discuss if this is right next week"
<file>
t23094 - Fixes bug in admin logout

When an admin logge out of the admin ares, they
could not log in to the memebers area because their
session[:user_id] was still set to the admin ID. This patch
fixes the bug by setting session[:user_id] to nil when
any user logs out of any area.
</file>
===== Viewing commit log =====
  git log
limit number of commit messages
  git log -n 5
time periods
  git log --since=2012-06-14
  git log --until=2012-06-15
  git log --author="Kevin"
  git log --grep="Init" (global reg ex search)

====== 4. Git Concepts and Architecture ======
===== Three tree architecture =====
  * Two tree
    * working
      * commit
    * repository
      * checkout

  * Three tree
    * working
      * git add file.txt
    * staging index
      * git commit file.txt
    * repository
The third tree allows a way to get changes ready for the commit and still allow modifications to the working directory until time to commit.

===== Git workflow =====
  * New file creation is in the working directory.
  touch file.txt
  * git add places the file in the staging directory
  git add file.txt
  * git commit saves the changes to the repository
  git commit ...
  * edited file is modified in the working directory
  cat >> file.txt
  some changes
  ^d
  * add the changes to the staging index
  git add file.txt
  * commit changes
  git commit ...

===== Using has values (SHA-1) =====
  * Git generates a checksum for each change set
    * checksum algorithms convert data into a simple number
    * sam data always equals same checksum
  * data integrity is fundamental
    * changing data would change checksum
  * Git uses SHA-1 hash algorithm to create checksums
    * 40-character hexadecimal string (0-9,a-f)

  git log

Each commit has the parent hash as part of the commit to ensure data integrity between commits.

===== Working with the HEAD pointer =====
HEAD
  * reference pointer to "tip" of current branch in repository
  * last state of repository; what was last checked out
  * points to parent of next commit
    * where writing commits takes place
kind of like the record head of a tape player

  cd .git
  ls -la
  cat HEAD
  cd refs
  ls -la
  cd heads
  cat master
  git log (to review what the SHA-1 refers to)
  git log HEAD (is the same as above)

====== 5. Making Changes to Files ======

===== Adding Files =====

  git status
  git add second_file.txt
  git status
  git commit -m "Add second file to project"
  git status
  git log
  git add third_file.txt
  git status
  git commit -m "Add third file to project"
  git status
  git log

===== Editing Files =====
Same procedure as adding files.

Make changes with text editor
  git status
  git add first_file.txt
  git log
files can be in staging directory and not in staging and "status" will show the differences.

===== Viewing Changes with diff =====

view differences between repository version and the working directory
  git diff
less started with -S will chop long lines. -R will show raw and wrap lines

Inside less, use - shift S to toggle back and forth between wrap and chop lines.
===== Viewing only staged changes =====

view differences between repository verison and the staging index version
  git add first_file.txt
  git diff --staged
This used to be called --cached which was confusing. Both return the same information.

===== Deleting files =====
  git add *
  git commit -m "files to delete"
Two ways to delete files. One it to delete file_to_delete1.txt from the OS which can put it in the trash, then:
  git rm file_to_delete1.txt
  git commit -m "deleted file_to_delete1.txt"
  git status
  git log
The other way is to just do the whole remove from git, which will bypass the trash.
  git rm file_to_delete2.txt
  git commit -m "Removed second file"
===== Moving and renaming files =====
Two ways: from the OS, then tell git, or just let git do it.
  (rename a file)
  git status
  (then git shows a deleted file and a new untracked file.)
  git add primary_file.txt
  git rm first_file.txt
  git status
  (then shows the file to be renamed even with up to 50% changes.)

  git mv second_file.txt secondary_file.txt
  git status will then show the file renamed

Moving is similar
  git mv third_file.txt first_directory/third_file.txt

  git commit -m "reorganized file structure by moving files"

====== 6. Using Git with a Real Project ======
===== Editing the support Phone Number =====
TextMate allows files to be edited as a project by dragging the folder onto TextMate.

Make desired changes. Then use git status and git diff to see the changes
  git status

  git diff contact.html
Shows the lines with +/- designating changed lines. 
  * Uses the Less pager.
  * "f" and "b" can be used to move forward and back pages of text.
  * Start "less" with -r to fold lines (set in global config.)
  * or, hit the minus key and Shift-S + return

To highlight changes specifically (not on a line by line level):
  git diff --color-words contact.html

==== commit the changes ====
  git add contacts.html
or
  git add .
or
  git commit -am "changed phone number."
Note: -a includes all changed files, but not new files or deleted files.

===== Editing the backpak file name and links =====
Changing file names within git is a good option.
  git mv tours/tour_detail_backpack.html tours/tour_detail_backpack_cal.html

  git status
will show that the file has been renamed.

Make changes to the html by using a global search and change the references.

  git add tours.html
  git add /tours
  git status
Note: git reports just the rename for the file that was renamed.

A good practice is to make commits one change at a time. If after renaming files, a context change is made, then go ahead and commit the name change, then add the changed file(s) for another commit.

====== 7. Undoing Changes ======
===== Undoing working directory changes =====
Show files modified.
  git status
Show specific changes
  git diff

Could be ambiguous:
  git checkout index.html
  git checkout resources
This will retrieve the named thing (file, directory or branch), (index.html or resources) and make my directory look like that.

Better practice:
  git checkout -- index.html (-- Means stay on the current branch.)
These checkout(s) will blow away the contents of the present directory.

===== Unstaging files =====
To get a hint:
  git status

  git reset HEAD <file>...
===== Amending Commits =====
Changing prior commits to git cannot really be made because of the hash integrity. The last commit is editable however.

With a change that needs to be commited
  git add resources.html
  git commit -m "Rearrange the items to bring on a trip"
  git log
Make another change
  git status
  git add resources.html
  git commit --amend -m "Rearrange the items to bring on a trip"
Or just the message can be updated which will change the hash of the last commit.

Remember, once another commit is made, that commit cannot be changed.

===== Retrieving old versions =====
  git status
  git log

copy the first few letters of the hash, say 10 or so.
  git checkout 2907d12603a34 -- resources.html
  git status (shows it is moved into the staging index
  git diff --staged
  git commit -m "This commit reverts 2907d12603a34" (adding the hash is a good idea)

Undo the checkout and commit:
  git status
  git reset HEAD resources.html (puts it back in the working directory.)
  git checkout -- resources.html

===== Reverting a commit =====
Takes all the changes and go back to that version
  git log
  git revert eb2f28564fd3cf

  git -n (does not automatically do the commit.)

A merge is performed if the changes cannot be easily undone with a mirror image commit.

===== Using reset to undo many commits =====
  git reset
Allows us to specify where the HEAD pointer points to.

git reset is analogous to rewinding a cassette and recording over it.

    --soft
     - does not change the staging index or working directory
    --mixed (default)
     - Changes staging index to match repository
     - does not change working directory
    --hard
     - changes staging index and working directory to match repository
     - USE WITH CAUTION as it removes from the working directory any changes since the commit
===== Demonstrating a soft reset =====
  git log
If we want to undo, we could "revert" or we can rewind and record over.

Open up a new text file and paste the output of the "git log" because once we rewind, we will not be able to see the log of changes since.

<file>
$ git log
commit 78687188cca4cbd9374da062952eaa2db3a0ba7f
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 15:41:36 2016 -0500

    moved items in list.

commit eb2f28564fd3cfe164be4329a78b3eac5c80ddd1
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 14:54:00 2016 -0500

    Initial-07_02

commit 2907d12603a340c02a4c846e3709991a7d0c21b9
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:37 2012 -0400

    Removed contractions from contact page text

commit cf78db87140d6470393177c7dc634d706422acfa
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:21 2012 -0400

    Renamed Backpack Cal file for clarity

commit 1506576375b15992e3d1f0a3d8965550efb89fa2
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:02:29 2012 -0400

    Changed 24 hour support number to 4314

commit c4b913ef2da10a5d72c1ab515ada11ffb9c343e0
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 15:04:41 2012 -0400

    Initial commit
</file>


  $ cat .git/HEAD
  ref: refs/heads/master
  $ cat .git/refs/heads/master
  eb2f28564fd3cfe164be4329a78b3eac5c80ddd1

  git reset --soft eb2f28564fd3

  git status
Shows the reverted file.

  git diff
show no changes

  git diff --staged
shows changes

All it does is move the head pointer.

A re-commit could be made:
  git commit -m "Doing the commit over again."

or just change the head pointer back.
  git reset --soft 78687188cca4cb



===== Demonstrating a mixed reset =====
Same as soft except it makes the staging index look the same as the repository

Make a copy of the log so we have the commit hashes:
<file>
$ git log
commit 78687188cca4cbd9374da062952eaa2db3a0ba7f
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 15:41:36 2016 -0500

    moved items in list.

commit eb2f28564fd3cfe164be4329a78b3eac5c80ddd1
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 14:54:00 2016 -0500

    Initial-07_02

commit 2907d12603a340c02a4c846e3709991a7d0c21b9
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:37 2012 -0400

    Removed contractions from contact page text

commit cf78db87140d6470393177c7dc634d706422acfa
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:21 2012 -0400

    Renamed Backpack Cal file for clarity

commit 1506576375b15992e3d1f0a3d8965550efb89fa2
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:02:29 2012 -0400

    Changed 24 hour support number to 4314

commit c4b913ef2da10a5d72c1ab515ada11ffb9c343e0
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 15:04:41 2012 -0400

    Initial commit
</file>

  git reset --mixed eb2f28564fd3c
  Unstaged changes after reset:
  M	resources.html

So, `--mixed` will change the staging index to what is in the repository. Now, a
  git diff
will show changes, and 
  git diff --staged
will not indicate changes.

We could restage and re-commit.
  git add .
  git status
===== Demonstrating a hard reset =====
This will destuctively rewrite files in the current directory.

<file>
$ git log
commit 78687188cca4cbd9374da062952eaa2db3a0ba7f
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 15:41:36 2016 -0500

    moved items in list.

commit eb2f28564fd3cfe164be4329a78b3eac5c80ddd1
Author: Steve Edwards <steve.edwards@vt.edu>
Date:   Tue Dec 20 14:54:00 2016 -0500

    Initial-07_02

commit 2907d12603a340c02a4c846e3709991a7d0c21b9
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:37 2012 -0400

    Removed contractions from contact page text

commit cf78db87140d6470393177c7dc634d706422acfa
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:28:21 2012 -0400

    Renamed Backpack Cal file for clarity

commit 1506576375b15992e3d1f0a3d8965550efb89fa2
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 16:02:29 2012 -0400

    Changed 24 hour support number to 4314

commit c4b913ef2da10a5d72c1ab515ada11ffb9c343e0
Author: Kevin Skoglund <someone@nowhere.com>
Date:   Tue Jun 19 15:04:41 2012 -0400

    Initial commit
</file>

  git reset --hard eb2f28564fd3cfe164be
  git log
  git status
files have been changed and reverted.

We can move back to the latest commit if we know the hash, but at some point the commit would be garbage collected.
  git reset --hard 78687188cca4cbd93

Or make another commit.
  git reset --hard eb2f28564fd3cfe164be
  git log
  git status
are both clean and the files are rewound.

...make a change
  git status
  git commit -am "moved sunglasses above hat."
  git log

The overwritten commits are abandoned and will eventually get cleaned up.

===== Remove untracked files =====
Destructivly deletes files from the pwd.
  git clean

if some unneeded files, say text files, are in the directory, then git can purge them.

  cat > junk1.txt
  cat > junk2.txt
  cat > junk3.txt

Test run:
  git clean -n

  git add junk1.txt

Force:
  git clean -f
removes junk2 and 3

  git status
  git reset HEAD junk1.txt
removes junk1.txt from staging index
  git clean -f
removes junk1.txt
====== 8. Ignoring Files ======
===== Using .gitignore files =====

Create a file in the root of the project directory
  project/.gitignore

Can have very basic regular expressions
  `* ? [aeiou] [0-9]

negate expressions with !
  `*.php`
  !index.php
ignore all files in a directory with trailing slash
  assets/videos/
comment lines begin with #, blank lines are skipped

cat >.gitignore
<file>
tempfile.txt
.DS_Store
*.zip
*.gz
log/*.log
log.*.log.[0-9]
assets/photoshop/

assets/videos
# But don't ignore:
!assets/videos/tour_*.mp4
</file>
===== Understanding what to ignore =====
  * compiled source code
  * packages and compressed files
  * logs and databases
  * operating system generated files
  * user-uploaded assets (images, PDF's, videos)

https://help.github.com/articles/ignoring-files

https://github.com/github/gitignore
===== Ignoring files globally =====
  * ignore files in all repositories
  * setting not tracked in repository
  * user-specific instead of repository-specific

Create the .gitignore_global in base of home directory
  cat > ~/.gitignore_global
  .DS_Store
  .Trashes
  .Spotlight-V100

  git config --global core.excludesfile ~/.gitignore_global
===== Ignoring tracked files =====
Tracked files are not ignored even if the file is in .gitignore

  * Add file to .gitignore

Then

  git rm --cached tempfile2.txt
===== Tracking Empty Directories =====
Empty directories are not tracked.

  mkdir assets
  git status
  
Add:
  touch .gitignore
or
  touch .gitkeep

  git status
  git add assets/pdfs/
  git status
reveals a tracked file
  git commit -m "Add 'empty' directory with .gitkeep file in it"


====== 9. navigating the Commit Tree ======
===== Referencing commits =====
tree-ish is something that references part of a tree.
  * references a commit (sha-1 hash)
    * sha-1 hash
    * short sha-1 hash
      * at least 4 characters for a small project
      * unambiguous (8-10 characters)
    * HEAD pointer
      * always points to the commit of tip of the currently checked out branch
    * branch reference, or tag reference
    * ancestry
      * parent commit
        * `-HEAD^`, `acf87504^`, `master^`
        * `-HEAD~1`, `HEAD~`
      * grandparent commit
        * `HEAD^^`, `acf87504^^`, `master^^`
        * `-HEAD~1`
      * great-grandparent commit
        * `-HEAD^^^`, `acf87504^^^`, `master^^^`
        * `HEAD~3`
===== Exploring tree listings =====
  git ls-tree ...
  git help ls-tree
  git ls-tree HEAD
A tree is a directory

===== Getting more from the commit log =====
  git help log
  git log --oneline
  git log --oneline -3
  git log --since="2012-06-20"
  git log --after="2012-06-20" (same as previous)
  git log --until="2012-06-20"
  git log --before="2012-06-20" (same as previous)
  git log --since="2 weeks ago" --until="3 days ago"
  git log --since=2.weeks --until=3.days
  git log --author="Kevin Skoglund"
  git log --grep="temp"
  git log --online
  git log 2907d12..acf8750
  git log 2907d12..acf8750 --oneline
  git log c4b913.. index.html
  git log -p c4b913.. index.html
  git log --stat c4b913.. index.html
  git log --summary c4b913.. index.html
  git log --stat --summary c4b913.. index.html
  git log --format=oneline (returns full sha1)
  git log --format=short
  git log --format=meduim (default)
  git log --format=full
  git log --format=fuller
  git log --format=email
  git log --format=raw
  git log --graph (shows branches)
  git log --oneline --graph --all --decorate

===== Viewing commits =====
  git log --oneline
  git show cdb913e
  git show --format=online cdb913e
  git show --format=online HEAD
  git show --format=online HEAD^
  git show --format=online HEAD^^
  git show --format=online HEAD~3
  git help show
  git ls-tree master
  git show 6fa98b (Tree-ish object "tree" instead of "blob", which is a directory)
  git show 497db6 (Tree-ish object "blob" instead of "tree", which is a file)
  git show index.html (is not the same thing as a tree-sh and will not work.)

===== Comparing commits =====
Show changes between working directory and Staging index
  git diff
Show changes between staging index and the repository or the HEAD (where the HEAD pointer is pointing)
  git diff --staged
  git diff --cached (same thing)

  git log --oneline
Passing in one sha1 will show the difference between that commit and the pwd.
  git diff cdae0ed
  git diff cdae0ed tours.html
  git diff cdae0ed..cdae0ed
  git diff cdae0ed..cdae0ed tours.html
  git diff cdae0ed..HEAD
  git diff cdae0ed..HEAD^^

  git log --oneline
  git diff --stat --summary 1506576..HEAD
  git diff -b 1506576..HEAD
  git diff --ignore-space-change 1506576..HEAD (same as -b)
  git diff --ignore-all-space 1506576..HEAD (same a w)
  git diff -w 1506576..HEAD (ignore all space changes)
  
  
====== 10. Branching ======
===== Branching overview =====
Branches of the master can be created and merged back into the master or discarded. It is a good way to test ideas in code that might not make it, rather than undoing a bunch of commits.

The HEAD pointer will point to the same commit until changes on the created branch are made and committed.

===== Viewing and creating branches =====
To show the branches before creating:
  git branch
The * indicates the current branch
  cat .git/HEAD
  ls -la .git/refs/heads
  cat .gits/refs/heads/master

To create the branch:
  git branch new_feature
  ls -la .git/refs/heads
  cat .git/refs/heads/new_feature (shows hash of master since nothing has been committed yet.)
  cat .git/HEAD (still points to master)
===== Switching branches =====
  pwd
  git branch
  cat .git/HEAD

  git checkout new_feature
  git branch
  cat .git/HEAD

Make a change
  git status
  git commit -am "Modified title on index.html"
  git log --oneline
  git checkout master
  git branch
  git log --oneline
  
===== Creating and switching branches =====
  git branch
To create a new branch and checkout at the same time
  git checkout -b shorten_title
  git status (note the checkout help option to discard changes)
  git add index.html
  git commit -m "Shorten title in index.html"
  git log --oneline
  git checkout new_feature
  git log --oneline
  git checkout master
  git log --oneline
  git log --graph --oneline --decorate --all


===== Switching branches with uncommitted changes =====
Working directory must be " mostly clean". Untracked files will not be deleted, as they will just show up as untracked files in any branch switched to.
  git status

  git checkout shorten_title
make a change to index.html
  git status (shows unstaged change)
  git checkout master (will fail with an error.)

Two options. One is to discard changes.
  git status
  git checkout -- <filename>
Second is to commit the changes
  git commit -am "Swap out dash for colon in index.html title."

Third is to stash the changes. Described later.




===== Comparing branches =====
  git branch
  git diff master..new_feature
  git diff --color-words new_feature..shorten_title
  git diff --color-words new_feature..shorten_title^

To check if a branch has been completely included in a branch.
  git branch --merged
  
===== Renaming branches =====
  pwd
  git branch
  git diff master..new_feature
  git branch -m new_feature seo_title
  git branch --move new_feature seo_title (same as previous)
===== Deleting branches =====
  git branch
  git checkout master
  git branch branch_to_delete
  git branch -d branch_to_delete

  git branch branch_to_delete
  git checkout branch_to_delete
  git branch -d branch_to_delete (will fail to delete)
make a change
  git commit -am "Changed Title"
  git log --oneline
  git checkout master
  git branch
  git branch -d branch_to_delete (will fail to delete)
  git branch


===== Configuring the command prompt to show the branch =====
Make sure .git-completion.bash and git-prompt.sh are installed and .git-completion is loaded from .bash_profile

<file>
  $ cat ~/.bash_profile 

if [ -f ~/.git-completion.bash ]; then
  source ~/.git-completion.bash
fi
if [ -f ~/git-prompt.sh ]; then
  echo $PS1
  source ~/git-prompt.sh
  PS1='[\u@\h \W$(__git_ps1 " (%s)")]\$ '
  # Default seems to be '\h:\W \u\$'
fi
</file>

  export PS1='>>>>>'
  export PS1='$(_git_ps1 "(%s)") > '
  export PS1='\W$(_git_ps1 "(%s)") > '

====== 11. Merging Branches ======
===== Merging code =====
Start with a clean working directory with everything committed.

Checkout the branch the is receiving the changes.
  git checkout master
  git merge seo_title

===== Using fast-forward merge vs. true merge =====
A fast forward merge can occur when no changes have been made on the originating branch. It can simply move the commit to the timeline and point the HEAD at it.

To take a look:
  git log seo_title --oneline -3
  git log master --oneline -3

Force a commit while merging so a commit message can be logged.
  git merge --no-ff branch
Merge only if ff merge can be performed.
  git merge --ff-only branch

True merge
  git checkout master
  git branch
make a change to contact.html
  git status
  git add contact.html
  git commit -m "edit contact.html title"
  git log --oneline -3
  git log shorten_title --oneline -3
  git merge shorten_title (text editor will be involked to add a commit message.)
===== Merging Conflicts =====
If the same line is changed on the same file in different branches, then a conflict will arrise
  git checkout -b 'text_edits'
Make changes to mission.html on lines 65, 66, 67 and 68.
  git status
  git commit -am "Text edits on mission.html page"
  git checkout master
Make changes to mission.html on lines 67
  git commit -am "Replace quotes on mission.html page"
  git log --oneline
  git log text_edits --oneline
  git merge text_edits
the conflicting files get lines inserted with the conflicts that will need to be fixed manually.
===== Resolving merge conflicts =====
If PS1 is set, the prompt will show (master|MERGING)

Three choices
  * abort merge
  * resolve the conflicts manually
  * use a merge tool (not recommended until fully understanding merging manually)

Abort
  git merge --abort

Resolve manually

Search for "<<<<" in the conflicting file
  git log --oneline -3
  git show 432e8c6 (This will show differences.)
Find the proper changes and remove all the <<<< and ===== and extra parts.
  git add mission.html
  git commit (a message is not necessary.)

  git log --graph --oneline --all --decorate

  git mergetool --tool=
  git mergetool
===== Exploring strategies to reduce merge conflicts =====
  * keep lines short
  * keep commits small and focused (don't make changes "while in the file".)
  * beware stray edits to whitespace
    * spaces, tabs, line returns
  * merge often
  * track changes to master (merge master into branch as changes get made.)

====== 12. Stashing Changes ======
===== Saving changes in the stash =====
  git branch
  git checkout shorten_title
  git branch --merged
modify mission.html
  git status
  git checkout master (will not work since changes to the shorten_title branch have been made!)
so stash them instead
  git stash save "changed mission.html page title"
A stash is not a commit, it can be a little sloppier.
  git log --oneline -3

runs get reset hard HEAD and made what is in the repo our pwd

Untracked files can be included with the git stash "include untracked" option.
===== Viewing stashed changes =====
list changes
  git stash list
show files changed
  git stash show stash@{0}
show files changed with diff
  git stash show -p stash@{0}
===== Retrieving stashed changes =====
Stashed changes can be brought (merged) into whatever branch you are on like merging.
  git stash pop (removes code from stash. Used most of the time.)
  git stash apply (leaves a copy in stash)
By default, it will pop the first stash

A specific stash can be popped.
  git stash pop stash@{2}




===== Deleting stashed changes =====

  git stash list
  git stash drop stash@{0}

make a change tours.html

  git status
  git stash save "changed mission and tours page title"
  git stash list
  git status

Make a change to explorers.html

Delete everything in stash all at once

  git stash clear
====== 13. Remotes ======
===== Using local and Remote repositories =====
Remotes are the central repository online. GitHub is one as such is BitBucket. Changes are sent to the server with a "push" command. This creates a branch called origin/master that matches the changes pushed to the repository on our local machine. This origin allows changes to be made by others while a local copy is also being modified. The changes have to be merged together to combine the changes. Origin/master just tries to stay in sync with the version on the remote.

  push (send local commits to remote server and creates orgin/master and tries to stay in sync with server master.)
  fetch (brings remote changes into origin/master. A merge needs to be done to move changes to local master.
  merge (fast forward merge)

Do commits locally, fetch changes from server, then merge locally, and then push up to the server.


===== Setting up a GitHub account =====
Create an account. Free ones are public only.

Create a new repository (repo)

Initialize with README will add a README file. .gitignore is also available.

The setup page show commands to add the remote server origin branch
===== Adding a remote repository =====
  git remote
Create a origin brach by convention for the main 
  git remote add origin https://...
  git remote
To list remotes verbosely and show the url
  git remote -v
To remove a remote alias
  git remote rm orgin (or whatever alias name used)
  
===== Creating a remote branch =====
Push (-u track branch change) (alias for remote repository) (branch)
  git push -u origin master

  cat .git/config
master references origin, and origin references a url.

  ls -la .git/refs/remotes/
  ls -la .git/refs/remotes/origin/
  cat .git/refs/remotes/origin/remotes
stores branch hashes

  git branch -r
  git branch -a
===== Cloning a remote repository =====
Find the link on github path to the repository and use it following:
  git clone https://github.com/kevinskoglund/explore_california.git
To put it in a different named folder
  git clone https://github.com/kevinskoglund/explore_california.git lynda_version
  git branch
Only the master branch by default (which can be changed) will be cloned unless -b specifies a different branch.
===== Tracking remote branches =====
The dash u option tracks changes on a remote server.

  cat .git/config
  ...
    [branch "master"]
        remote = origin
        merge = refs/heads/master

Create a branch that does not track don't use the `-u` option
  git branch non_tracking
  git push origin non_tracking
Does not create a branch paragraph in the config file

To manually create:
  git config branch.non_tracking.remote origin
  git config branch.non_tracking.merge refs/heasd/master
with git 1.7:
  git branch --set-upstream non_tracking origin/non_tracking

===== Pushing Changes to a remote repository =====
Make some changes to tours.html
  git commit -am "some changes made to tours.html"
  git log --oneline
  git log --oneline origin/master (my copy of remote branch)
  git diff origin/master..master

  git push origin master
Since it is a tracking branch, just:
  git push

  git log --oneline
  
===== Fetching changes from a remote repository =====
  pwd
  git log --oneline -5
  git log --oneline -5 orgin/master
  git branch
  git branch -r (to show remote branches)

git does not automatically sync changes, it just looks at the local copy.

  git fetch origin
  git fetch (if only one repository is specified)

  * Always fetch before you work.
  * Fetch before you push.
  * Fetch often

===== Merging in fetched changes =====
  pwd
  git branch -a
  git diff origin/master..master

  git merge origin/master
  git log --oneline -3 master

git pull = git fetch + git merge
===== Checking out remote branches =====
  pwd
  git branch
  git branch -r

A non-tracking branch can be retrieved and set to track:
  git branch non_tracking origin/non_tracking
  git branch
  cat .git/config (shows tracked branch)

To delete the local copy of the branch:
  git branch -d non_tracking
  git branch -r

create a branch and check it out:
  git checkout -b non_tracking origin/non_tracking
  git branch (shows the active branch is non_tracking.)
  git checkout master (to go back to the master branch.)


===== Pushing to an updated remote branch =====
If commits have been made to the remote server since the local fetch, git will not push.

  git fetch
  git merge origin/master
  git push


===== Deleting a remote branch =====
  pwd
  git branch -a

old way:
  git push origin :non_tracking
  git branch -r (it's gone!)
The colon is shorthand for from:to and if nothing is on the left side, it assumes nothing goes to the right and deletes it.

The shorthand can also be used to push from one to another
  git push origin non_tracking:non_tracking

Newer, more intuitive way:

First push the local copy of the branch back up
  git push origin non_tracking
  git branch -r
  git push origin --delete non_tracking
  
===== Enabling collaboration =====
From the github project homepage, select admin and add collaborators.

For an open source project, create a fork.
===== A collaboration workflow =====
  git checkout master
  git fetch
  git merge origin/master
Create a branch to work on changes
  git checkout -b feedback_form
Create a new file called feedback.html
  git add feedback.html
  git commit -m "Add customer feedback form"
  git fetch
  git push -u origin feedback_form

Co-workers point of view:
  git clone ??? (if not already cloned)
  git checkout master
  git merge origin/master
Now grab the remote version of feedback_form
  git checkout -b feedback_form origin/feedback_form
  git log
  git show 84b6adf0
or
  git show feedback_form (if it is the last commit made.)
make a change to the feedback_form
  git commit -am "Adde tour selector to feedback form"
  git fetch
  git push

My p.o.v.
  git fetch
  git log -p feedback_form..origin/feedback_form
if changes are acceptable, them merge them with the local copy
  git merge origin/feedback_form
Go back to master and update it for other remote changes.
  git checkout master
  git fetch
  git merge origin/master
Master is now up-to-date. Now merge in the feedback_form
  git merge feedback_form
  git push
====== 14. Tools and Next Steps ======
===== Setting up aliases for common commands =====
  pwd
Set aliases in the global git config file so that they work for all projects
  ls -la ~/
The file is .gitconfig

  git config --global alias.(abbreviated command) (actual command)
  git config --global alias.st status
  cat ~/.gitconfig
  git config --global alias.co checkout
  git config --global alias.ci commit
  git config --global alias.
  git config --global alias.br branch
  git config --global alias.df diff
  git config --global alias.dfs "diff --staged"
  git config --global alias.dfc "diff --cached"
  git config --global alias.logg "log --graph --decorate --oneline --abbrev-commit --all"
  
  
===== Using SSH keys for remote login =====
https://help.github.com/articles/set-up-git

https://help.github.com/articles/caching-your-github-password-in-git/

https://help.github.com/articles/connecting-to-github-with-ssh/
===== Exploring integrated development environments =====
Textmate > Bundles > Git

  * Vim
  * Emacs
  * TextMate
  * Eclipse
  * Netbeans
  * Visual Studio
  * IntelliJ
  * RubyMine
  * PHPStorm

===== Exploring graphical user interfaces =====
  * GitWeb
    * https://git.wiki.kernel.org/index.php/Gitweb

==== Graphical User Interfaces for Mac ====
  * GitX http://gitx.org
  * GitHub http://mac.github.com
  * SourceTree http://sourcetreeapp.com
  * Tower http://git-tower.com
  * SmartGit http://syntevo.com/smartgit
  * Gitbox http://gitboxapp.com

==== Graphical User Interfaces for Windows ====
  * TortiseGit http://code.google.com/p/tortoisegit
  * GitHub http://windows.github.com
  * Git Extensions http://code.google.com/p/gitextensions
  * SmartGit http://syntevo.com/smartgit

List of others: https://git.wiki.kernel.org/index.php/InterfacesFrontendsAndTools

===== Understand Git hosting =====
A git server needs to be set up.

  * GitHub http://github.com
  * Bitbucket http://bitbucker.org
  * Gitorious http://gitorious.org

==== Git Self-Hosting ====
  * Gitosis http://github.com/tv42/gitosis
    * development stopped a few years ago
  * Gitolite http://github.com/sitaramc/gitolite
    * based on gitosis