View source for Git/C2/Merging-and-Deleting-branches/English

'''Title of script:''' Merging and deleting branches

'''Author:''' Priya K

'''Keywords:''' '''Video tutorial, git, branch, merging, deleting, revert merging'''



{| style="border-spacing:0;"
| style="border:1pt solid #000000;padding:0.097cm;"| <center>Visual cue</center>
| style="border:1pt solid #000000;padding:0.097cm;"| <center>Narration</center>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 1:

Merging and deleting branches
| style="border:1pt solid #000000;padding:0.097cm;"| Welcome to the spoken tutorial on''' Merging and deleting branches'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 2:Learning Objectives



| style="border:1pt solid #000000;padding:0.097cm;"| In this tutorial, we will learn about

* '''Merging'''
* Revert '''merging''' and
* Deleting '''branches'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 3:

System requirement



| style="border:1pt solid #000000;padding:0.097cm;"| For this tutorial, I am using

* '''Ubuntu Linux 14.04'''
* '''Git 2.3.2''' and
* '''gedit Text Editor'''

You can use any editor of your choice.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 4:

Pre-requisites


| style="border:1pt solid #000000;padding:0.097cm;"| To follow this tutorial

* You must have knowledge of basics of''' Git''' commands and''' branching '''in '''Git'''.
* If not, for relevant '''Linux''' tutorials, please visit our website.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| Earlier in the series, we learnt to create '''branches'''.


Now, we will learn how to merge two '''branches'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 5:

Merging diagram



| style="border:1pt solid #000000;padding:0.097cm;"| This diagram illustrates how the '''new-module''' '''branch''' is merged with the '''master branch'''.


This is done in the''' C9''' commit.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 6:

After Merging



| style="border:1pt solid #000000;padding:0.097cm;"| After '''merging''', the '''commits''' of''' new-module''' are added to''' master''' branch.


Let me explain how it works.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Press Ctrl+Alt+T to open the''' terminal'''
| style="border:1pt solid #000000;padding:0.097cm;"| First, we will open our''' Git repository mywebpage''' which we created earlier.


Press''' Ctrl+Alt+T''' to open the''' terminal'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' cd mywebpage''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| To go into our''' Git repository''', type''' cd space mywebpage'''


and press''' Enter'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| I will continue to use''' html''' files for demonstration. 


You may use any file type of your choice.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| From here onwards, please remember to press the '''Enter key '''after typing every '''command '''on the '''terminal'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git branch''' and press''' Enter'''


Highlight''' master''' and''' new-chapter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let us check the '''branch '''list by typing''' git space branch'''.


We can see that we have two branches named''' master''' and''' new-chapter'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight''' new-chapter >> '''Highlight''' master'''
| style="border:1pt solid #000000;padding:0.097cm;"| The''' new-chapter''' '''branch '''was created earlier in this series and''' master''' is the default '''branch'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight''' * master'''
| style="border:1pt solid #000000;padding:0.097cm;"| Currently, we are in the''' master''' '''branch'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| We will check the''' Git log''' by typing''' git space log space hyphen hyphen oneline'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git checkout new-chapter''' and press '''Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s go to''' new-chapter''' branch and check the''' Git log'''.


Type''' git space checkout space new-chapter'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git space log space hyphen hyphen oneline''' 

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| Now we will compare the '''commits''' of''' master''' and''' new-chapter''' '''branches'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the first 4 commits of''' master''' and''' new-chapter''' branch
| style="border:1pt solid #000000;padding:0.097cm;"| These four '''commits''' are common to both the '''branches'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight''' Added story.html in new-chapter branch'''


Highlight '''Added chapter two in history.html'''
| style="border:1pt solid #000000;padding:0.097cm;"| '''"Added story.html in new-chapter branch"''' is in''' new-chapter branch.'''


And''' "Added chapter two in history.html"''' is in''' master branch.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| After '''merging, “Added story.html in new-chapter branch” commit '''will be added in the''' master branch'''.


<<PAUSE>>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git merge master''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let me demonstrate how to '''merge '''now.


Type''' git space merge space master'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| '''Gedit''' opens up automatically to receive the '''commit''' message.


Recall that we have configured''' gedit''' as the core '''editor''' of''' Git'''.


If you had configured another '''editor''', then that one will open up.


If you are using a '''Git''' version that is below '''1.9''', then the '''editor''' may not open. 


So, you may skip the next step.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the first line of gedit


Save and close the gedit
| style="border:1pt solid #000000;padding:0.097cm;"| I use the default '''commit '''message as it is.


If you want to give any other message related to the '''merging''', then type it here.


Now save and close the''' editor'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| We will check the''' Git log''' again.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the commits
| style="border:1pt solid #000000;padding:0.097cm;"| You can see that the '''commits '''of''' master branch '''are merged with''' new-chapter branch.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight the merge commit message
| style="border:1pt solid #000000;padding:0.097cm;"| You can also see a '''commit '''message for the '''merging.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git checkout master''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Next, we will go to''' master branch '''and check the '''commits'''.


Type''' git space checkout space master'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s check the''' Git log'''.


Here we should have seen '''master branch commits''' along with '''new-chapter commits'''.


But the '''Git log '''shows '''master branch commits '''only.

|-
| style="background-color:#ffffff;border:1pt solid #000000;padding:0.097cm;"| Highlight the '''Git log'''
| style="border:1pt solid #000000;padding:0.097cm;"| Ideally, we should have '''merged''' the''' new-chapter branch '''to the''' master branch'''.


But we have '''merged '''it the other way around.


That’s why we can't see the '''merging commit '''in the''' master branch'''.


<<PAUSE>>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| So, how can we revert this '''merging'''?

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| For this, we will have to go back to the''' new-chapter branch.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git space checkout space new-chapter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git space checkout space new-chapter'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git reset --hard HEAD~''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| To revert the '''merge''', type''' git space reset space hyphen hyphen hard space HEAD tilde'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight''' HEAD~'''
| style="border:1pt solid #000000;padding:0.097cm;"| Recall that latest revision is always''' HEAD''' and latest minus 1 revision is always''' HEAD tilde'''.


So we have used '''HEAD tilde''' to get the previous revision of '''merging'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s check the''' Git log''' once again.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| We can see that the '''merging''' is discarded now.


<<PAUSE>>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| We will now '''merge''' the''' new-chapter branch '''to the''' master branch'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git checkout master''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| We will go to '''master branch''' first by typing''' git space checkout space master'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s check the''' Git log '''again.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git merge new-chapter''' and press''' Enter'''


Close the''' editor'''
| style="border:1pt solid #000000;padding:0.097cm;"| To '''merge''', we will type''' git space merge space new-chapter'''


Give your '''merging commit''' message in the '''gedit'''.


Then save and close the''' editor.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git log --oneline''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Again check the''' Git log'''.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| We can see that our''' new-chapter branch''' has been successfully merged to''' '''the '''master branch.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type '''git merge new-chapter''' and press '''Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s try to '''merge '''it again.


Type '''git space merge space new-chapter'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight “'''Already up-to-date”'''
| style="border:1pt solid #000000;padding:0.097cm;"| Now we see a message that says “'''Already up-to-date'''”. 


This is a good way to verify whether we '''merged '''or not. 


<<PAUSE>>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| After '''merging, '''the''' new-chapter branch '''can be deleted from the''' Git repository.'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git branch -d new-chapter''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| To delete the '''branch''', type''' git space branch space hyphen d space new-chapter'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Type''' git branch''' and press''' Enter'''
| style="border:1pt solid #000000;padding:0.097cm;"| Let’s check the '''branch''' list once again by typing''' git space branch'''


We can't see''' new-chapter branch '''anymore as it has been deleted.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Highlight''' -d''' in the deleting command
| style="border:1pt solid #000000;padding:0.097cm;"| To delete a '''branch '''without '''merging''', 
*use''' hyphen D''' in uppercase 
*instead of '''hyphen d '''in lowercase.


<<PAUSE>>

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| With this, we come to the end of this tutorial.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 7:

Summary


| style="border:1pt solid #000000;padding:0.097cm;"| Let us summarize.


In this tutorial, we have learnt about

* '''Merging'''
* Revert '''merging '''and
* Deleting '''branches'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 8:

Assignment

* Check the commits of the branch''' chapter-two''' which you created in the previous assignment
* Merge it to the''' master''' branch
* Delete the''' chapter-two''' branch


| style="border:1pt solid #000000;padding:0.097cm;"| As an assignment

* Check the '''commits''' of the '''branch chapter-two''' which you created in the previous assignment
* Merge it with the''' master branch '''and
* Delete the''' chapter-two branch'''

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 9:

Acknowledgement


| style="border:1pt solid #000000;padding:0.097cm;"| The video at the following link summarises the Spoken Tutorial project.


Please download and watch it.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 10:

Spoken Tutorial Workshops



| style="border:1pt solid #000000;padding:0.097cm;"| The Spoken Tutorial Project Team conducts workshops and gives certificates to those who pass online tests.


For more details, please write to us.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| Slide 11:

Acknowledgement


| style="border:1pt solid #000000;padding:0.097cm;"| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.


More information on this Mission is available at the following link.

|-
| style="border:1pt solid #000000;padding:0.097cm;"| 
| style="border:1pt solid #000000;padding:0.097cm;"| This is Priya from IIT Bombay. Thanks for joining.

|}