Udacity lesson 5

Question 1

point out certain commits in order to let them stand out

Answer 1

git tag -a some_tag -m “Message to be added”

-a stands for annotated. You can also add a message through -m

last commit: just like above, the commits somewhere before:

git tag -a tags_name commit_s_number_in_7_digits -m “Message”

Question 2

see all tags that are in the repository

Answer 2

git tag

but to see where they are - git log

Question 3

what does git tag -a blah do?

Answer 3

it it adds a tag to the last commit. The tag is visible if you want to see all the commits, also with –oneline

Question 4

delete a tag

Answer 4

git tag -d tag_name

Question 5

how do branches work?

Answer 5

you move the pointer called head to the specific commit in a specific branch. That branch then appears in your code editor, and there the next commit will be added.

So if you point at the last commit of one of the existing branches, it will add to that branch. If you point your “head” somewhere in the middle of the branch, it will create a new branch from there.

Question 6

create a new branch

Answer 6

situate the pointer at the right commit somehow

git branch name_of_branch

Question 7

switch between branches

Answer 7

git checkout name_of_the_branch_to_switch_to

Question 8

start a new branch at a certain commit

Answer 8

git branch name_of_the_branch commits_number

git checkout name_of_the_branch

or your could do the first one also with the name of the branch that’s on the same commit now (it’s HEAD is there) as the one you want

Question 9

list out the branches in a repository

Answer 9

git branch

Question 10

what happens when you run git checkout branch_name?

Answer 10

removes all files and directories from the Working Directory that Git is tracking (files that Git tracks are stored in the repository, so nothing is lost)

goes into the repository and pulsl out all of the files and directories of the commit that the branch points to

Question 11

how to know in which branch I am?

Answer 11

git branch

the one with * is the current one

Question 12

delete a branch

Answer 12

switch to another branch

git branch -d branch_name

Question 13

why isn’t it deleting my branch? what to do?

Answer 13

because it has unique commits

merge it with some other branch or

git branch -D branch_name

Question 14

Switch and create branch in one command

Answer 14

git checkout -b new_branch_name

Question 15

see commits of all branches in a single output

Answer 15

git log –oneline –graph –all

–graph creates the visualization of the tree

–all ensures all branches are represented

Question 16

merge branches

Answer 16

checkout the branch that will encompass another branch, then

git merge name-of-branch-to-merge-in

so not the one at which you are, but the other one, that should be incorporated

Question 17

undo the merge

Answer 17

git reset –hard HEAD^

Question 18

what will git do when you use the git merge command?

Answer 18

look at the branches that it’s going to merge

look back along the branch’s history to find a single commit that both branches have in their commit history

combine the lines of code that were changed on the separate branches together

makes a commit to record the merge

Question 19

fast-forward merge

Answer 19

when the branch that’s merged in contains next steps for the checked out branch

will move the currently checked out branch forward until it points to the same commit that the other branch is pointing to. So it moves the HEAD (the pointer), it doesn’t create a new commit

Question 20

When a merge is performed and fails, that is called

Answer 20

a merge conflict

Question 21

what will I see if a merge conflict occurs?

Answer 21

Git will try to combine as much as it can, but then it will leave special markers (e.g. > > > and < < < ) that tell you where you need to manually fix.

Question 22

when does a merge conflict happen?

Answer 22

when the exact same line(s) are changed in separate branches

Question 23

what do the indicators of the merge conflict mean?

Answer 23

Question 24

resolve merge conflict

Answer 24

remove all conflict indicators

write the piece of the code that causes conflict the way you want it to be, delete all the alternative versions, save, stage and commit the new version

you could also just commit it with all the indicators, but that’s a bit useless, and how will this code work anyways?

! Be careful that a file might have merge conflicts in multiple parts of the file, so make sure you check the entire file for merge conflict indicators - a quick search for < < < (without spaces) should help you locate all of them.