add branches content

lectures/02-Git/slides.qmd

@@ -23,14 +23,164 @@ author: "Lukas, Georgiana, Theresa, Tobi"
 
 ## Branches 
 
-(local repo - 5 slide - Georgiana)
+* are versions of the code identified with a name (besides existing hash)
+* are used to encapsulate the changes required for a new feature or a bugfix 
+* allow incremental development without impacting the `main` branch
 
-* why use a branch? 
-* create/delete local branch 
-* rebase branch
-* git add after editing a conflicting file - go through the text file
-* merge branch into main
-* stop lecture: do exercises
+---
+
+### Create a branch 
+```bash
+# check the branches before creating a new one
+git branch
+* master 
+
+# create a new branch
+git branch b1
+
+# check the branches after adding a new branch
+git branch
+  b1
+* master
+```
+
+---
+
+### Switch branches
+```bash
+# check the branches to see the current branch
+git branch
+  b1
+* master
+
+# switch to the new branch
+git checkout b1
+
+# check the branches to see the current branch
+git branch
+* b1
+  master
+```
+
+---
+
+### Rename a branch
+
+```bash
+# check the branches before rename
+git branch
+* b1
+  master
+
+# rename current branch
+git branch -m feature-new-sorting-algo
+
+# check the branches after rename
+git branch
+* feature-new-sorting-algo
+  master
+```
+
+---
+
+### Compare branches
+```bash
+git diff master..feature-new-sorting-algo
+
+diff --git a/test.txt b/test.txt
+index faab00e..f4ecce0 100644
+--- a/test.txt
++++ b/test.txt
+@@ -1 +1 @@
+-this is a test.
++this is a test in a branch.
+
+```
+
+---
+
+### Rebase a branch
+```bash
+# make changes in two branches
+...
+
+# rebase branch feature-new-sorting-algo on main
+git rebase master
+
+CONFLICT (content): Merge conflict in test.txt
+error: could not apply 2ce7874... modify in branch
+hint: Resolve all conflicts manually, mark them as resolved with
+hint: "git add/rm <conflicted_files>", then run "git rebase --continue".
+hint: You can instead skip this commit: run "git rebase --skip".
+hint: To abort and get back to the state before "git rebase", run "git rebase --abort".
+Could not apply 2ce7874... modify in branch
+
+```
+
+---
+
+### Rebase a branch - edit conflicts
+```bash
+# view and edit the conflicting file
+<<<<<<< HEAD
+this is a test in master branch.
+=======
+this is a test in a branch.
+>>>>>>> 2ce7874 (modify in branch)
+
+# fix the conflict and continue the rebase
+git add test.txt
+git rebase --continue
+[detached HEAD 3699a57] modify in branch
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+Successfully rebased and updated refs/heads/feature-new-sorting-algo.
+```
+
+---
+
+
+### Merge a branch 
+```bash 
+# move to destination branch
+git checkout master
+
+# merge source branch into destination branch
+git merge feature-new-sorting-algo
+Updating c3f5771..3699a57
+Fast-forward
+ test.txt | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+```
+
+---
+
+### Delete a branch
+```bash
+# check current branches
+git branch
+  feature-new-sorting-algo
+* master
+
+# delete a branch
+git branch -d feature-new-sorting-algo
+
+# check branches after delete
+git branch
+*  master
+```
+
+---
+
+### Exercise time!
+
+1. create a branch
+2. rename the branch
+3. make changes in both branches (`master` and the new one)
+4. merge/rebase the new branch on master
+5. check the log for the master branch
+6. delete the new branch 
+
+---
 
 ## Best practices