script

#!/bin/bash

function restartHistory() {
  #This function obliterates a branch
  #$1 is the name of the branch to obliterate
  echo "##restarting history"
  git checkout $1
  git checkout --orphan newbranch
  git add -A
  git commit -am "start over"
  git branch -D $1
  git branch -m $1
  git push -f origin $1

  rm *
  git add -A
  git commit -m "blank files"
  git push -f origin $1
}

function remakeBranch () {
  #This function resets a branch to master's current history
  #$1 is the name of the branch to reset
  echo "##remaking branch"
  git checkout master
  git checkout -b newbranch
  git add -A
  git commit -am "start from master"
  git branch -D $1
  git branch -m $1
  git push -f origin $1
}

function writeFile() {
  #This function writes some text to a file
  #$1 is the file name
  #$2 is the first line
  #$3 is the second line
  #$4 is the third line
  rm $1
  touch $1
  echo $2 >> $1
  echo $3 >> $1
  echo $4 >> $1
}

function makeChangesInBranch() {
  #This function makes changes to a file and then commits those changes to the correct branch
  #$1 is the file name
  #$2 is the first line
  #$3 is the second line
  #$4 is the third line
  #$5 is the branch name
  
  git checkout $5
  writeFile $1 $2 $3 $4
  git add -A
  git commit -m "changes"
  git push origin $5
}

#This is the start of the script
#delete the old local version and obliterate it
echo "##starting script"
rm -rf gittester
git clone https://github.com/djshapiro/gittester.git
cd gittester
restartHistory master

#pull remote versions of the two branches
git fetch origin v1
git checkout v1
git fetch origin v2
git checkout v2

#Make a file and put some stuff in it
git checkout master
echo "##making a new file"
writeFile file1 "stuff" "more-stuff" "[1,2,3]"
git add -A
git commit -m "added some stuff to file1"
git push -f origin master
remakeBranch v1
remakeBranch v2

#Put some changes in v1
makeChangesInBranch file1 "stuff-and-a-thing." "more-stuff" "[1,2,3,4]" v1

#Put some changes in v2
makeChangesInBranch file1 "stuff" "less-stuff" "[1,2]" v2

#merge them together. This represents the "bad" merge; we merge v2 into v1.
git checkout v1
git merge v2
makeChangesInBranch file1 "stuff" "less-stuff" "[1,2]" v1

#now make more changes in v1
makeChangesInBranch file1 "stuff" "less-stuff" "[1,2,3]" v1

#and let's try a correct merge (v1 into v2)
git checkout v2
git merge v1