merge conflict resolution

gistfile1.md

Simple example of a merge conflict

####Overview

• add a file
• create new branch
• modify same section of file in both branches in a conflicting way
• attempt to merge one branch into the other

####Process

1. add file

(default27)MK63HADV33:testrepo hugh3869$ echo -e "a\nb\nc" >> mergetest
(default27)MK63HADV33:testrepo hugh3869$ cat mergetest
a
b
c

1. commit

(default27)MK63HADV33:testrepo hugh3869$ git commit -a -m "added merge test"
[master 8d2f76a] added merge test
 1 files changed, 3 insertions(+), 0 deletions(-)
 create mode 100644 mergetest

1. create feature branch but still on master (use checkout -b to branch and checkout)

(default27)MK63HADV33:testrepo hugh3869$ git branch feature

1. make a change on master branch

(default27)MK63HADV33:testrepo hugh3869$ sed -i 's/b/d/' mergetest

1. commit

(default27)MK63HADV33:testrepo hugh3869$ git commit -a -m "mergetest master change (b-->d)"
[master a393a81] mergetest master change (b-->d)
 1 files changed, 1 insertions(+), 1 deletions(-)

1. switch to feature branch

(default27)MK63HADV33:testrepo hugh3869$ git checkout feature
Switched to branch 'feature'

1. make a conflicting change

(default27)MK63HADV33:testrepo hugh3869$ sed -i 's/b/e/' mergetest

1. commit

(default27)MK63HADV33:testrepo hugh3869$ git commit -a -m "mergetest feature change (b-->e)"
[feature 8682551] merge test feature change (b-->e)
 1 files changed, 1 insertions(+), 1 deletions(-)

1. checkout master and attempt to merge

(default27)MK63HADV33:testrepo hugh3869$ git checkout master
Switched to branch 'master'
Your branch is ahead of 'origin/master' by 2 commits.
(default27)MK63HADV33:testrepo hugh3869$ git merge feature
Auto-merging mergetest
CONFLICT (add/add): Merge conflict in mergetest
Automatic merge failed; fix conflicts and then commit the result.

1. merge fails due to conflict, view the resulting file:

(default27)MK63HADV33:testrepo hugh3869$ cat mergetest
a
<<<<<<< HEAD
d
=======
e
>>>>>>> feature
c

1. choose the option you want for the conflicting section (d/e), delete the other section and remove the delimiters (<<<===>>>)

(default27)MK63HADV33:testrepo hugh3869$ sed -i '/^[<=>e]/d' mergetest

1. add and commit

(default27)MK63HADV33:testrepo hugh3869$ git add mergetest
(default27)MK63HADV33:testrepo hugh3869$ git commit -a -m "resolved feature merge"

1. look at the history

(default27)MK63HADV33:testrepo hugh3869$ git log --graph --oneline
*   7954798 resolved feature merge
|\
| * 8682551 mergetest feature change (b-->e)
* | a393a81 mergetest master change (b-->d)
|/
* 8d2f76a added merge test
* 9e29f4d fix travis yaml
* 3c5de95 add .travis.yml
* e95a88b playing with travis
* 0b2fe45 Initial commit