Git/C2/Merging-and-Deleting-branches/English-timed

Time	Narration
00:01	Welcome to the spoken tutorial on Merging and deleting branches.
00:06	In this tutorial, we will learn about Merging,
00:10	revert merging and deleting branches.
00:14	For this tutorial, I am using: Ubuntu Linux 14.04
00:20	Git 2.3.2 and gedit Text Editor.
00:26	You can use any editor of your choice.
00:29	To follow this tutorial, you must have knowledge of basics of Git commands and branching in Git.
00:37	If not, for relevant Linux tutorials, please visit our website.
00:42	Earlier in the series, we learnt to create branches.
00:47	Now, we will learn how to merge two branches.
00:51	This diagram illustrates how the "new-module" branch is merged with the "master" branch.
00:58	This is done in the C9 commit.
01:01	After merging, the commits of new-module are added to master branch.
01:06	Let me explain how it works.
01:09	First, we will open our Git repository mywebpage which we created earlier.
01:16	Press Ctrl+Alt+T to open the terminal.
01:20	To go into our Git repository, type: cd space mywebpageand press Enter.
01:29	I will continue to use html files for demonstration.
01:33	You may use any file type of your choice.
01:38	From here onwards, please remember to press the Enter key after typing every command on the terminal.
01:45	Let us check the git branch list by typing git space branch.
01:51	We can see that we have two branches named master and new-chapter.
01:57	The new-chapter branch was created earlier in this series and master is the default branch.
02:05	Currently, we are in the master branch.
02:08	We will check the Git log by typing git space log space hyphen hyphen oneline.
02:17	Let’s go to new-chapter branch and check the Git log.
02:21	Type: git space checkout space new-chapter
02:27	Type: git space log space hyphen hyphen oneline
02:33	Now, we will compare the commits of master and new-chapter branches.
02:38	These four commits are common to both the branches.
02:42	"Added story.html in new-chapter branch" is in new-chapter branch.
02:48	And, "Added chapter two in history.html" is in master branch.
02:54	After merging, “Added story.html in new-chapter branch” commit will be added in the master branch.
03:02	Let me demonstrate how to merge now.
03:05	Type: git space merge space master
03:09	Gedit opens up automatically to receive the commit message.
03:14	Recall that we have configured gedit as the core editor of Git.
03:20	If you had configured another editor, then that one will open up.
03:26	If you are using a Git version that is below 1.9, then the editor may not open.
03:33	So, you may skip the next step.
03:36	I use the default commit message as it is.
03:40	If you want to give any other message related to the merging then type it here.
03:46	Now save and close the editor.
03:50	We will check the Git log again.
03:54	You can see that the commits of master branch are merged with new-chapter branch.
04:00	You can also see a commit message for the merging.
04:04	Next, we will go to master branch and check the commits.
04:09	Type: git space checkout space master
04:14	Let’s check the Git log.
04:17	Here, we should have seen master branch commits along with new-chapter commits.
04:22	But, the Git log shows master branch commits only.
04:27	Ideally, we should have merged the new-chapter branch to the master branch.
04:32	But we have merged it the other way round.
04:36	That’s why we can't see the merging commit in the master branch.
04:41	So, how can we revert this merging?
04:45	For this, we will have to go back to the new-chapter branch.
04:50	Type: git space checkout space new-chapter
04:54	To revert the merge, type: git space reset space hyphen hyphen hard space HEAD tilde
05:04	Recall that latest revision is always HEAD and latest minus 1 revision is always HEAD tilde.
05:12	So, we have used HEAD tilde to get the previous revision of merging.
05:18	Let’s check the Git log once again.
05:22	We can see that the merging is discarded now.
05:26	We will now merge the new-chapter branch to the master branch.
05:31	We will go to master branch first by typing git space checkout space master
05:38	Let’s check the Git log again.
05:42	To merge, we will type: git space merge space new-chapter.
05:48	Give your merging commit message in the gedit.
05:52	Then save and close the editor.
05:55	Again, check the Git log.
05:58	We can see that our new-chapter branch has been successfully merged to the master branch.
06:05	Let’s try to merge it again.
06:08	Type: git space merge space new-chapter
06:13	Now, we see a message that says “Already up-to-date”.
06:17	This is a good way to verify whether we merged or not.
06:22	After merging, the new-chapter branch can be deleted from the Git repository.
06:28	To delete the branch, type: git space branch space hyphen d space new-chapter
06:36	Let’s check the branch list once again by typing git space branch
06:43	We can't see new-chapter branch anymore as it has been deleted.
06:48	To delete a branch without merging, use hyphen D in uppercase instead of hyphen d in lowercase.
06:56	With this, we come to the end of this tutorial.
07:00	Let us summarize.
07:02	In this tutorial, we have learnt about Merging, revert merging and deleting branches.
07:09	As an assignment, check the commits of the branch chapter-two which we created in the previous assignment.
07:16	Merge it with the master branch and delete the chapter-two branch.
07:22	The video at the following link summarizes the Spoken Tutorial project.
07:27	Please download and watch it.
07:30	The Spoken Tutorial Project team conducts workshops and gives certificates to those who pass online tests.
07:38	For more details, please write to us.
07:41	Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
07:48	More information on this mission is available at the following link.
07:53	This is Priya from IIT Bombay. Thanks for joining.

Contributors and Content Editors

PoojaMoolya, Sandhya.np14