15 ms·

Learn Git Branching

717 points by redDragon 14y ago

jedberg 14y ago
It would be great if the help page popped up when I first load the site, so I don't have to guess and type "help" at the prompt to find out the purpose of the site. :)
- wldlyinaccurate 14y ago
  I didn't even realise you could type "help". There definitely needs to be some sort of introduction prompt otherwise people (like me) are just gonna leave feeling like they've learned nothing. Still, nice idea.
  - bpatrianakos 14y ago
    Agreed. I'm like you and I was just committing, branching, and merging but learning nothing while clicking around. I'm glad I know now though because I can totally use a lesson on branching. I think branching in Git is one of the most misunderstood parts of Git. I can't tell you how many times I've almost screwed up a repo because I made some mistake merging branches and not pulling from the correct branch when working on a different machine. To make matters worse, if you use Git to deploy into production, testing, and staging environments like I do you run the risk of pushing development or untested code into production by accident. I know I've definitely pushed code meant only for one branch (or feature) into production without merging with master... it gets confusing but needless to say it didn't take long before things stopped working and I realized my mistake. Branching is huge, awesome, powerful, but I know I as well as a lot of developers I know could use a good lesson on it.
    - alinajaf 14y ago
      The implementation of branching in git is so fantastically simple (its literally a commit hash in a file, `cat .git/refs/heads/master` if you don't believe me) that it boggles the mind that so many developers have so much issue with it.
      - bpatrianakos 14y ago
        The implementation may be simple but I think what gets people is building a mental model of all your different remotes and branches. If you're working on a single machine this is simple. Add in another remote and it's still simple but adds complexity. Add in 3 remotes, 3 development machiness, and oh say 3 branches and the mental model is hard to juggle. I develop on 3 different machines and even after about 6 months of this setup which is very close to the example I gave I still mess things up because I don't think to check what branch I'm on when I switch machines and pull from the wrong one and other little mistakes like that. Branching really is a very simple thing to understand but what I think gets people in the end is building a mental model of one's own setup and creating good habits like always running `git status` when sitting down at a new machine to be sure you're on the branch you think you are, always pushing to your main remote before switching machines, and making sure to push to the correct branch in that remote, and so on.
  - xxbondsxx 14y ago
    Sorry, I got to this thread late (author here). The demo link: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo Is far better
- xxbondsxx 14y ago
  My bad (author here), this was submitted without my knowledge :P The demo here: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo Shows the help page, an example level, and the whole shebang
  - jedberg 14y ago
    Ah, that's much better!
leetrout 14y ago
I'm only getting started with the tutorials but this looks really promising! I also like the fact that there are no instructions on the page which would make this really useful as a quiz tool to see how students / interview candidates / etc approach the problem space. I fully intend to fork and try to make my own levels when I get some free time. Great concept. Is this based on something else similar or entirely new?
- xxbondsxx 14y ago
  LearnGitBranching is somewhat the intersection between try.github.com (which has the whole fake command line thing) and the diagrams drawn in the git manpages. Try.github was an awesome way to present a tutorial, but it wasn't the full-fledged demo I wanted it to be. A few months later I came out with this!
edgarvaldes 14y ago
I don't get how it works.
- deweerdt 14y ago
  You can: - 'git checkout -b branch_name' to create a branch - 'git checkout branch_name' to switch branches - 'git commit' to add dummy commits (no need to git add stuff) Edit: formatting
  - deleted 14y ago
    [deleted]
  - famulus 14y ago
    You can also: -'git rebase branch_name' -'git merge branch_name' -'git checkout C6' to enter a detached head state
  - asveikau 14y ago
    Congrats, you just gave a more helpful introduction than the page. :-)
- deleted 14y ago
  [deleted]
joebeetee 14y ago
Beautiful. Great job.
seivan 14y ago
Great job. Would be cool if you told people about git flow once you notice the pattern further in.
miga 14y ago
Please support git fast-forward!
deleted 14y ago
[deleted]
alinajaf 14y ago
Excellent work! I've wanted an easy way to explain git branching to people and from now on I'll point them to this.
- tiziano88 14y ago
  Same! Sometimes I would like to introduce my coworkers to the amazing world of git, but it's hard to convince them without showing them a concrete example, this one is a pretty nice overview, and also useful for advanced users! I just got a better, more intuitive understanding of what detached HEAD really means thanks to it!
  - msoad 14y ago
    Git is amazing, I just wish if there was a better conflict resolving approach in Git.
    - alinajaf 14y ago
      Do you really? I like the fact that git doesn't try anything clever when it hits a conflict and asks you to fix by hand. Have you found an automatic conflict resolution tool that you liked before?
    - _ikke_ 14y ago
      resolving conflicts is not something machines can do. There needs to be a human to decide what is a correct outcome.
  - xxbondsxx 14y ago
    No problem, really glad you like it. I think one of the most important distinctions as well is the difference between rebasing and merging -- I show this off in the demo link: http://pcottle.github.com/learnGitBranching/index.html?demo http://pcottle.github.com/learnGitBranching/index.html?demo I never understood why some repos only accept rebase commits until I actually looked up how the graph is wildly different depending on the command
dljsjr 14y ago
Absolutely fantastic tutorial, but as most other people here have mentioned there should probably be some indication that you should type help to get started.
- xxbondsxx 14y ago
  I just pushed the site live, so it starts off with a help dialog and links to the demo. Future visitors should hopefully get a better experience! My apologies again -- I only noticed it was on HN when I got an email about it...
  - dljsjr 14y ago
    Your use of live visualizations of the state of the repository is probably the single best part of the app. Seriously, very very well done.
    - xxbondsxx 14y ago
      Thanks! Really appreciate the feedback, I worked really hard on the animations and there were a ton of corner cases to solve in order for them to work. But I do think they serve a huge educational value, so I'm glad to hear the work (and code) paid off.
memming 14y ago
type 'level' to start.
- cpayne 14y ago
  Wow! How did you find that?
  - kaichanvong 14y ago
    I typed help first.
- mitchelllc 14y ago
  type 'level' to select level
dsjoerg 14y ago
very nice idea. when/if this supports git push i'll come back and play some more. i'm a total git noob, git makes me crazy and maybe this will help clarify things for me.
- d0m 14y ago
  I suggest you take the time to learn the "core" before memorizing all the commands.. everything will be so much easier : )
insteadof 14y ago
Seems only Chrome exists as a browser. All others need not apply.
- xxbondsxx 14y ago
  Should work on Firefox, Chrome, and Safari. Anything specific you are noticing in another browser?? I rely pretty heavily on the box model for layout, but if you look at the CSS I included almost every browser extension (even Opera)
  - jazz 14y ago
    For example the buttons does not work in the levels dialog. I would make a pull request if I could figure out how to build it with Grunt...
    - xxbondsxx 14y ago
      Fixed! Totally my bad, click event properties are super browser-specific
      - jazz 14y ago
        jQuery is here for that... You should use event.target.
  - test001only 14y ago
    http://imgur.com/XvK3kFY http://imgur.com/XvK3kFY - the layout of the box is messed up in Firefox. Using Firefox version - 18.0.2. Works great in chrome though. Thanks for the nice tutorial!
  - rexreed 14y ago
    It doesn't really layout well in my version of Firefox (18.0.2) - see the output here: http://imm.io/WxqQ http://imm.io/WxqQ and here: http://imm.io/Wxr8 http://imm.io/Wxr8 You can't see what's happening and the box seems to be improperly sized and spaced as well as problems with the terminal-style text editing window. The text flows off the bottom and cursor is misaligned: http://imm.io/WxrS http://imm.io/WxrS
jlgreco 14y ago
I would try it out but, fullscreened, I get the message "That window size is not supported :-/" How about letting me worry about that and continue anyway? What is the worst that could happen, I have to use a scrollbar?
- xxbondsxx 14y ago
  I support a fairly wide range of zoom levels... from +3 levels zoomed in to almost any level zoomed out. The main reason why I can't do more than 4 is the way canvas pixels interact with screen pixels and some of the text positioning logic. If you're at a normal zoom level and getting that message, certainly let me know -- the zoom level detection logic is a unfortunately pretty hacky.
  - Flimm 14y ago
    Please improve the error message to at least tell me what window sizes and zoom levels are supported.
    - xxbondsxx 14y ago
      I'm removing this for now, my apologies! This is what happens when a WIP gets submitted
  - evincarofautumn 14y ago
    It gave me the same message on my netbook (1024x600) at 100% zoom. I had to zoom out a few levels to make it happy, but then I couldn’t read the text. :(
nodesocket 14y ago
What is the difference between doing: git checkout -b bugFix git commit git checkout master git commit git merge bugFix master And git branch bugFix git commit git checkout master git commit git merge bugFix master
- jspiros 14y ago
  Creating a branch with git branch bugFix does not automatically check it out, so you'd have to follow it up with git checkout bugFix but if you do git checkout -b bugFix it will create the branch and then check it out all in one step.
  - nodesocket 14y ago
    Yup, makes sense. Thanks.
  - xxbondsxx 14y ago
    Yep! Exactly. The status of the current branch your on is designated by the asterisk (like in real git), but in retrospect I guess it could be a bit more clear...
- micampe 14y ago
  git checkout -b bugFix creates the branch and puts you on that branch, git branch bugFix creates the branch and leaves you where you are, so in your first example you are committing on the branch and then merging to master, in the second example you are always committing to master. try it in the website and you’ll see that in the second case bugFix never changes. the merge will say nothing needs to be done because bugFix already contains all changesets in master.
xxbondsxx 14y ago
Wow! Author here, did not expect this to get submitted to HN yet (was going to finish out a few more levels this weekend and clean everything up). Forgive the giant "TODO" in the help dialog The link everyone should see is the demo: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo That shows a few example commands, the completion of a level, and finishes with the help dialog. Some interesting technical highlights - I made heavy use of javascript "Promises" to route control through the entire app. The source code has some nice examples, but it would be callback spaghetti without it - You can import and export trees to share with your friends ("import tree" and "export tree" commands) - You can build levels from within the app with "build level". The intro diaog should step you through the process - It even supports interactive rebasing! Try it out with "git rebase -i HEAD~3" Git is a fairly complex too that can be explained really well graphically. I never understood what I was doing until I saw diagrams in the git manpages and various books around on the internet. I wanted there to be an interactive form of these diagrams but it didn't exist --- so I built it. 9,000 lines of JS later I have this. There's still some polishing to be done, but I'd love for the community to share their knowledge about different git workflows and different ways to explain git concepts. I tried to make the bar for contributing as low as possible. You can build a level and submit a pull request without even cloning the repo!
- nwhitehead 14y ago
  Very nice! I worked through all the levels you have and everything worked great, it was a lot of fun. Some notes: I "cheated" and used cherry-pick before it was introduced, not sure if that should or should not be allowed. Sometimes I was frustrated because my graph looked like the goal except for "ghosted" nodes, had to go back and figure out a different way to solve the level the right way. I wished I had an "undo" feature to take back moves rather than resetting everything. Lots more hints would be good, this stuff is hard. Honestly I learned more git in the last 10 minutes than I've learned in a year of using git, or from several hours reading git tutorials.
  - xxbondsxx 14y ago
    Wow that's great to hear! Seriously, really glad someone found it useful. That's the entire reason I built it. Levels support a "disable-map" that will prevent certain commands from executing. I somewhat foolishly assume that users only learn commands as I introduce them, but I should go back and lock down some of the levels. Also, I'm working on a way to compare trees without the ghosted nodes --- it's a bit tricky, but if anyone loves graph traversal and would love to help, chime in on github!
r4pha 14y ago
shameless plug: www.srctree.net - Ace editor + git + canvas for viewing commits/branches. I built it about a year ago, mostly for learning and fun. I haven't advertised it a lot but it seems relevant in here. I hope it's not off topic!
- THINKBEFORE 14y ago
  totally do not understand what this should do. please give some intro...
  - r4pha 14y ago
    I guess I need to rethink the whole layout. Under 'tips' there is a small explanation but might still be confusing. There's also a 'see an example' on the bottom, but I guess it's not that helpful either. Someone gave me a nice hint of doing a landing page with explanation and a huge 'start coding' button. I'll do that :)
- contingencies 14y ago
  Interesting but how to get other code in there is not so clear. Could be useful as an educational tool, with nicer defaults.
  - r4pha 14y ago
    I'm not sure I get it. You can start coding and just keeping on commiting and it will handle branching automatically. No doubts that I should make that clear somewhere.
- cormacrelf 14y ago
  I just wish you could merge and rebase.
  - r4pha 14y ago
    That would be one of the next steps. I just released an really simple MVP and got my head around other projects. I'm sure gonna refactor the thing eventually and make some things clearer.
shurcooL 14y ago
Nice stuff. This kind of branching visualisation is highly useful. I'd like to work with that kind of interface. I suppose I should use gitk or something similar? How did you create the branch visualization? Did you use some sort of library for displaying and animating connected nodes, or is it all coded from scratch?
- prophetjohn 14y ago
  Looks like raphael https://github.com/pcottle/learnGitBranching/tree/master/lib https://github.com/pcottle/learnGitBranching/tree/master/lib
- xxbondsxx 14y ago
  I had to code it all from scratch unfortunately :-/ I looked at d3.js, arbor.js, and a ton of other libraries but none of them supported the tree layout I had in mind. Apparently visual tree layouts are PhD dissertation topics so there's a wide variety out there I think a lot of educational value is in the animations as well, so it made sense to roll my own. The majority of the code involves all the visual and GUI elements -- re-implementing git (ironically) wasn't too bad!
js-coder 14y ago
Dude, this is epic! Really great work.
g3orge 14y ago
you need to replay the solutions slower...
wildmXranat 14y ago
Since the author mentions that it's not ready for submission and use yet, I won't complain that I didn't know what to do with this demo at first. After reading these comments, it became obvious how great the thing is and going back with that in mind made the app more enjoyable
archgoon 14y ago
This tutorial is great, but it propagates a misconception about git. "A commit in git is a recorded set of changes that you have made" Git commits are _not_ deltas. They are entire snapshots of the repository and a single (optional) pointer to an ancestor commit[1]. Git may handle _compression_ in terms of deltas (see 'Packfiles' in [2]), but logically, a commit should be thought of as equivalent to the state of all files that are being tracked. That difference is that if you were only looking at diffs, commits would be the _edges_ of a graph, rather than a node plus a single edge. This is why rebases change the commit SHAs but not merges (and why merges create a new commit). This is why if you are on a merge branch, 'git checkout HEAD~3' may not bring you to where 'git log' would naively suggest. Version control systems that actually do think of 'commits' as pure 'deltas' are ones such as darcs. A really good, low level explanation, of git is here http://git-scm.com/book/en/Git-Internals-Git-Objects http://git-scm.com/book/en/Git-Internals-Git-Objects (BUG REPORT) The commit created with 'git merge b2' from branch b1 should have HEAD~1 point to the previous head of b1, not b2. (that said, this is a really cool thing. :) I look forward to the author adding support for conflict resolution. ) [1] http://git-scm.com/book/en/Git-Internals-Git-Objects#Commit-Objects http://git-scm.com/book/en/Git-Internals-Git-Objects#Commit-... [2] http://git-scm.com/book/en/Git-Internals-Packfiles http://git-scm.com/book/en/Git-Internals-Packfiles
- xxbondsxx 14y ago
  Thanks a ton for catching this. I guess there is a distinction to be made -- the compression might use delta's, but a commit specifies the entire state of the repository. It's a tricky line to walk though, because commands like "git show" and "git patch" clearly show the delta-like nature of a single commit. I also don't want newcomers to think that commits are heavy and should be used sparingly. I'm totally down to discuss this on a github issue with you, we could go over the wording. Maybe something like "a commit specifies the entire state of a repository, but is usually stored on disk as a set of changes"? EDIT: moving discussion to: https://github.com/pcottle/learnGitBranching/issues/6 https://github.com/pcottle/learnGitBranching/issues/6 EDIT: fixed in: https://github.com/pcottle/learnGitBranching/commit/168852b293697442ea458a96a9c17c15e87a5594 https://github.com/pcottle/learnGitBranching/commit/168852b2...
devin 14y ago
This is great. Adding this to my list of resources for beginners. The ability to build levels, export trees, etc. makes it even better.
ecoffey 14y ago
This is really really great. Good visualizations of how git works are really awesome and useful, so thanks! That said, the intro lesson introduces commits as exclusively deltas. This isn't accurate, and would probably cause confusion with later concepts. Commits are really snapshots of a tree object (with probably a whole lot of sub trees, and a whole lot of blobs). Since part of the commit meta-data is the parent sha, it's really easy for git to show you the delta, but at it's core git cares about linked snapshots of trees. I am now done being anal retentive :-) thanks again for the great site, excited to see it more fleshed out
- xxbondsxx 14y ago
  Discussion here, I'm updating as we speak: https://github.com/pcottle/learnGitBranching/issues/6 https://github.com/pcottle/learnGitBranching/issues/6
ExpiredLink 14y ago
I don't see how this could be helpful. Does the author imply that there exists only one branching and merging strategy for any CVS?
- Cthulhu_ 14y ago
  No? Else the link / project would be called "Learn CVS Branching"
cocoflunchy 14y ago
This is a great tool, thanks so much ! I have trouble understanding the rebase workflow: What is the difference between these two sequences? git checkout -b bugFix git commit -m "fix" git checkout master git commit -m "master stuff" git rebase bugFix git checkout bugFix git rebase master and git checkout -b bugFix git commit -m "fix" git checkout master git commit -m "master stuff" git checkout bugFix git rebase master git checkout master git rebase bugFix Is it just the order of the commits in the final tree that will be different? Or I am missing something else? Instinctively I would tend to do the first one, but that was not what lesson 4 expected...
- jedbrown 14y ago
  In both cases, the second 'git rebase' is just a fast-forward (moving the ref ahead without modifying the graph). Thus we need only distinguish what happens in the first 'git rebase', which is a different choice of which patch gets rewritten. Note that you can shorten git checkout bugFix git rebase master to git rebase master bugFix
- csense 14y ago
  Rebase works by discarding commits and replacing them with different commits. If you rebase, then anyone who has the old commits in their repo will have to use git reset --hard to switch to the new branch. In other words, rebase inconveniences all other users of a branch. So you can use it freely on branches that only you work on, but you should be reluctant to use it on branches used by other people -- especially popular branches like "master". If you use your first workflow, the app clearly shows that you discard the commit C3 ("master stuff") and replace it with a different commit C3'. This requires everyone on master to reset. If you use your second workflow, the commit that you're discarding is C2 ("fix") instead. This means that only people who checked out C2 on bugFix need to reset.
  - cocoflunchy 14y ago
    Thanks, that makes sense.
Flimm 14y ago
C1' has two meanings, one is the result of a rebase, and one is the result of a revert. I stared at level 2 of "master the rebase, Luke" for a while before I realised this. I think these two things should be have different notations (maybe C1' and C1^-1, or C1' and C1r).
- Flimm 14y ago
  In fact, I solved that level using only 'git revert' commands, which I don't think was the intended solution. And the displayed solution isn't complete: it asks the user to perform an interactive rebase. (I'm not complaining, just feedback.)
  - xxbondsxx 14y ago
    That's a good point. I should just disable revert in all levels except for those related to it. I rarely revert in practice so it's not a huge issue. Showing the concept of a "modified" commit is hard though. That's why I did all the C1' sillyness (like the man pages do). The apostrophes also scale nicely (up to C1'^99) where reverting a reverted rebased commit might make the text too big. EDIT: Fixed, see: https://github.com/pcottle/learnGitBranching/issues/7 https://github.com/pcottle/learnGitBranching/issues/7
alexzhan 14y ago
The back array does not function well.
snip596 14y ago
Awesome visualization, but it seems to deviate from how git works in a few instances. Take "level mixed2" for example. The initial branch checked out was "caption". I did "git rebase -i master" and picked both commits (no re-ordering). That created C2' and C3' which is not correct. C2' wouldn't have been created because it's the same tree as C2 with the same ancestor. I had other issues with that level as well. It seems to be teaching inefficient habits by forcing strange rebases rather than a single one with an "edit" on C2. I understand this might be a limitation on the (really cool) visualization, but maybe those levels shouldn't be included if you can't show the most intuitive way (at least to me) to accomplish the goal. Otherwise, awesome work!
orangethirty 14y ago
I would seriously consider packaging this as an enterprise teaching tool for developers. Companies buy this sort of tools for training. Very good commercial potential here.
- xxbondsxx 14y ago
  I also spoke to the Github guys about integrating this into their set of training tools (try.github and a few docs), but I think they got caught up with their full time responsibilities because I haven't heard back in a while. I could commercialize it but it deserves to be free!
  - polymatter 14y ago
    well, this is seriously awesome - especially if you intend to carry on with it. would you consider a gittip or similar, so I can buy you a coffee?
  - orangethirty 14y ago
    You do know that with the license you currently have in there anyone can just sell it, right? You don't have an issue with that?
    - xxbondsxx 14y ago
      I'd be really disappointed if someone added one level and started selling a zip file of the application to enterprises for $400 a pop. That being said, I've heard the GNU license is sometimes too prohibitive (albeit no definitive examples). If you know licenses at all, I'd love some advice
      - orangethirty 14y ago
        $400? This would sell for thousands in the right market. Add in training, and you have a long time gig here. This would even be a great online training business. So many possibilities. Right now, you cant be disappointed if the license allows it. If you have doubts, change it now. In terms of licenses, I'm not really an expert. But you could just roll your own. Just take the one you have right now, and remove what allows people to sell it. Still won't stop some people from doing it, though. For example, I forked your repo. Why? Because its such a nice platform, that I want to learn how it works. I saw that about other 20 people had forked it too. What is stopping them from putting up a website and selling it? Nothing. Nothing at all. Open source is awesome and all. But you have to also be aware that there are a lot of ruthless people out there waiting for programmers like you to put out software like this one under such licensing terms. Its like buying a car, and listing everyone you know as an owner in the title. Can't get mad when they sell it.
aymeric 14y ago
Would be nice to see the solution of a level, to compare it with what we have done (and to find the solution if we are stuck).
- xxbondsxx 14y ago
  You can type in "show solution" to see the solution for a level (after a prompt). I'll have to add this to some help dialog somewhere... (again I apologize about the discoverability for different commands -- was going to document all this before submitting)
  - aymeric 14y ago
    Thanks!
mappum 14y ago
My only criticism is that there a million modals you have to go through, and some are even multi page, adding complexity. I would rather have fewer modals/pages that show more text at once. But overall, this is super handy, great idea :)
mawuli 14y ago
Great work. I recently found a very practical use of Git. I call it the "Poor man's hot code loading". This is a post i just wrote on it http://blog.mawuli.me/2013/02/poor-mans-hot-code-loading-git-branch.html http://blog.mawuli.me/2013/02/poor-mans-hot-code-loading-git...
- homosaur 14y ago
  I like this, I use Git in this way on my testing server quite often.
joeblau 14y ago
This looks awesome! Thanks for putting this together. It's hard to keep something cool under wraps :)
2mur 14y ago
Awesome. Using some lovely client side tech: backbone, browserify. Going to have to really spend some time looking through the code. Cheers!
arasmussen 14y ago
I found it a bit annoying that the "Alert!" dialogs in the beginning looked like a window but didn't work like one whatsoever (couldn't minimize, close, maximize, or move around). Probably shouldn't make something look like a well-known UI if it doesn't behave like that UI, especially to the point where familiar buttons don't work.
fiatpandas 14y ago
Buggy in Firefox. Stoplight window buttons not correctly placed, and the popups aren't centered-- they just align to the upper left
justplay 14y ago
Great work. Thanks for releasing .
Tomino 14y ago
Awesome work, obviously author has spent a lot of time on this and thought it through. Even with advanced GIT skills, it made me think about few things.
newtang 14y ago
This is really well done. Nice job! Another direction you can go with this is to make a series of Git puzzles. Basically, starting with this diagram A, convert to diagram B in the least number of moves. To be extra useful, these could revolve around common Git pitfalls.
- charlieflowers 14y ago
  This is a fantastic idea! Just like chess puzzles, only for git. Would be a great deliberate practice tool.
  - newtang 14y ago
    Exactly, the chess puzzles are a perfect comparison.
deleted 14y ago
[deleted]
swah 14y ago
I thought I knew enough git, but the other day I was still able to lose my changes... Suppose I'm in master and already modified a file, and now I notice that it would be better to work on a devel branch with those changes, so I could pull upstream changes from master and merge locally. I think I did something like this: git stash git checkout -b devel git stash apply git add file.txt git commit -m "XYZ new changes" git checkout master git fetch git rebase origin/master (to avoid an empty merge, changes upstream were in independent files) git merge devel (to get commit "XYZ") In the end of this, I had lost my changes in file.txt.
happypeter 14y ago
Have tried merging and rebasing, absolutely wonderful!
sleepybrett 14y ago
I worked my way up to branch spaghetti, where I went into the deep end, the solution for it uses commands and concepts not well introduced in the proceeding 'puzzles' (rebase -i)

717 points by redDragon 14y ago

It would be great if the help page popped up when I first load the site, so I don't have to guess and type "help" at the prompt to find out the purpose of the site. :)

wldlyinaccurate 14y ago
I didn't even realise you could type "help". There definitely needs to be some sort of introduction prompt otherwise people (like me) are just gonna leave feeling like they've learned nothing. Still, nice idea.
- bpatrianakos 14y ago
  Agreed. I'm like you and I was just committing, branching, and merging but learning nothing while clicking around. I'm glad I know now though because I can totally use a lesson on branching. I think branching in Git is one of the most misunderstood parts of Git. I can't tell you how many times I've almost screwed up a repo because I made some mistake merging branches and not pulling from the correct branch when working on a different machine. To make matters worse, if you use Git to deploy into production, testing, and staging environments like I do you run the risk of pushing development or untested code into production by accident. I know I've definitely pushed code meant only for one branch (or feature) into production without merging with master... it gets confusing but needless to say it didn't take long before things stopped working and I realized my mistake. Branching is huge, awesome, powerful, but I know I as well as a lot of developers I know could use a good lesson on it.
  - alinajaf 14y ago
    The implementation of branching in git is so fantastically simple (its literally a commit hash in a file, `cat .git/refs/heads/master` if you don't believe me) that it boggles the mind that so many developers have so much issue with it.
    - bpatrianakos 14y ago
      The implementation may be simple but I think what gets people is building a mental model of all your different remotes and branches. If you're working on a single machine this is simple. Add in another remote and it's still simple but adds complexity. Add in 3 remotes, 3 development machiness, and oh say 3 branches and the mental model is hard to juggle. I develop on 3 different machines and even after about 6 months of this setup which is very close to the example I gave I still mess things up because I don't think to check what branch I'm on when I switch machines and pull from the wrong one and other little mistakes like that. Branching really is a very simple thing to understand but what I think gets people in the end is building a mental model of one's own setup and creating good habits like always running `git status` when sitting down at a new machine to be sure you're on the branch you think you are, always pushing to your main remote before switching machines, and making sure to push to the correct branch in that remote, and so on.
- xxbondsxx 14y ago
  Sorry, I got to this thread late (author here). The demo link: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo Is far better
xxbondsxx 14y ago
My bad (author here), this was submitted without my knowledge :P The demo here: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo Shows the help page, an example level, and the whole shebang
- jedberg 14y ago
  Ah, that's much better!

leetrout 14y ago

I'm only getting started with the tutorials but this looks really promising! I also like the fact that there are no instructions on the page which would make this really useful as a quiz tool to see how students / interview candidates / etc approach the problem space. I fully intend to fork and try to make my own levels when I get some free time. Great concept. Is this based on something else similar or entirely new?

xxbondsxx 14y ago
LearnGitBranching is somewhat the intersection between try.github.com (which has the whole fake command line thing) and the diagrams drawn in the git manpages. Try.github was an awesome way to present a tutorial, but it wasn't the full-fledged demo I wanted it to be. A few months later I came out with this!

edgarvaldes 14y ago

I don't get how it works.

deweerdt 14y ago
You can: - 'git checkout -b branch_name' to create a branch - 'git checkout branch_name' to switch branches - 'git commit' to add dummy commits (no need to git add stuff) Edit: formatting
- deleted 14y ago
  [deleted]
- famulus 14y ago
  You can also: -'git rebase branch_name' -'git merge branch_name' -'git checkout C6' to enter a detached head state
- asveikau 14y ago
  Congrats, you just gave a more helpful introduction than the page. :-)
deleted 14y ago
[deleted]

joebeetee 14y ago

Beautiful. Great job.

seivan 14y ago

Great job. Would be cool if you told people about git flow once you notice the pattern further in.

miga 14y ago

Please support git fast-forward!

deleted 14y ago

[deleted]

alinajaf 14y ago

Excellent work! I've wanted an easy way to explain git branching to people and from now on I'll point them to this.

tiziano88 14y ago
Same! Sometimes I would like to introduce my coworkers to the amazing world of git, but it's hard to convince them without showing them a concrete example, this one is a pretty nice overview, and also useful for advanced users! I just got a better, more intuitive understanding of what detached HEAD really means thanks to it!
- msoad 14y ago
  Git is amazing, I just wish if there was a better conflict resolving approach in Git.
  - alinajaf 14y ago
    Do you really? I like the fact that git doesn't try anything clever when it hits a conflict and asks you to fix by hand. Have you found an automatic conflict resolution tool that you liked before?
  - _ikke_ 14y ago
    resolving conflicts is not something machines can do. There needs to be a human to decide what is a correct outcome.
- xxbondsxx 14y ago
  No problem, really glad you like it. I think one of the most important distinctions as well is the difference between rebasing and merging -- I show this off in the demo link: http://pcottle.github.com/learnGitBranching/index.html?demo http://pcottle.github.com/learnGitBranching/index.html?demo I never understood why some repos only accept rebase commits until I actually looked up how the graph is wildly different depending on the command

dljsjr 14y ago

Absolutely fantastic tutorial, but as most other people here have mentioned there should probably be some indication that you should type help to get started.

xxbondsxx 14y ago
I just pushed the site live, so it starts off with a help dialog and links to the demo. Future visitors should hopefully get a better experience! My apologies again -- I only noticed it was on HN when I got an email about it...
- dljsjr 14y ago
  Your use of live visualizations of the state of the repository is probably the single best part of the app. Seriously, very very well done.
  - xxbondsxx 14y ago
    Thanks! Really appreciate the feedback, I worked really hard on the animations and there were a ton of corner cases to solve in order for them to work. But I do think they serve a huge educational value, so I'm glad to hear the work (and code) paid off.

memming 14y ago

type 'level' to start.

cpayne 14y ago
Wow! How did you find that?
- kaichanvong 14y ago
  I typed help first.
mitchelllc 14y ago
type 'level' to select level

dsjoerg 14y ago

very nice idea. when/if this supports git push i'll come back and play some more. i'm a total git noob, git makes me crazy and maybe this will help clarify things for me.

d0m 14y ago
I suggest you take the time to learn the "core" before memorizing all the commands.. everything will be so much easier : )

insteadof 14y ago

Seems only Chrome exists as a browser. All others need not apply.

xxbondsxx 14y ago
Should work on Firefox, Chrome, and Safari. Anything specific you are noticing in another browser?? I rely pretty heavily on the box model for layout, but if you look at the CSS I included almost every browser extension (even Opera)
- jazz 14y ago
  For example the buttons does not work in the levels dialog. I would make a pull request if I could figure out how to build it with Grunt...
  - xxbondsxx 14y ago
    Fixed! Totally my bad, click event properties are super browser-specific
    - jazz 14y ago
      jQuery is here for that... You should use event.target.
- test001only 14y ago
  http://imgur.com/XvK3kFY http://imgur.com/XvK3kFY - the layout of the box is messed up in Firefox. Using Firefox version - 18.0.2. Works great in chrome though. Thanks for the nice tutorial!
- rexreed 14y ago
  It doesn't really layout well in my version of Firefox (18.0.2) - see the output here: http://imm.io/WxqQ http://imm.io/WxqQ and here: http://imm.io/Wxr8 http://imm.io/Wxr8 You can't see what's happening and the box seems to be improperly sized and spaced as well as problems with the terminal-style text editing window. The text flows off the bottom and cursor is misaligned: http://imm.io/WxrS http://imm.io/WxrS

jlgreco 14y ago

I would try it out but, fullscreened, I get the message "That window size is not supported :-/" How about letting me worry about that and continue anyway? What is the worst that could happen, I have to use a scrollbar?

xxbondsxx 14y ago
I support a fairly wide range of zoom levels... from +3 levels zoomed in to almost any level zoomed out. The main reason why I can't do more than 4 is the way canvas pixels interact with screen pixels and some of the text positioning logic. If you're at a normal zoom level and getting that message, certainly let me know -- the zoom level detection logic is a unfortunately pretty hacky.
- Flimm 14y ago
  Please improve the error message to at least tell me what window sizes and zoom levels are supported.
  - xxbondsxx 14y ago
    I'm removing this for now, my apologies! This is what happens when a WIP gets submitted
- evincarofautumn 14y ago
  It gave me the same message on my netbook (1024x600) at 100% zoom. I had to zoom out a few levels to make it happy, but then I couldn’t read the text. :(

nodesocket 14y ago

What is the difference between doing: git checkout -b bugFix git commit git checkout master git commit git merge bugFix master And git branch bugFix git commit git checkout master git commit git merge bugFix master

jspiros 14y ago
Creating a branch with git branch bugFix does not automatically check it out, so you'd have to follow it up with git checkout bugFix but if you do git checkout -b bugFix it will create the branch and then check it out all in one step.
- nodesocket 14y ago
  Yup, makes sense. Thanks.
- xxbondsxx 14y ago
  Yep! Exactly. The status of the current branch your on is designated by the asterisk (like in real git), but in retrospect I guess it could be a bit more clear...
micampe 14y ago
git checkout -b bugFix creates the branch and puts you on that branch, git branch bugFix creates the branch and leaves you where you are, so in your first example you are committing on the branch and then merging to master, in the second example you are always committing to master. try it in the website and you’ll see that in the second case bugFix never changes. the merge will say nothing needs to be done because bugFix already contains all changesets in master.

xxbondsxx 14y ago

Wow! Author here, did not expect this to get submitted to HN yet (was going to finish out a few more levels this weekend and clean everything up). Forgive the giant "TODO" in the help dialog The link everyone should see is the demo: http://pcottle.github.com/learnGitBranching/?demo http://pcottle.github.com/learnGitBranching/?demo That shows a few example commands, the completion of a level, and finishes with the help dialog. Some interesting technical highlights - I made heavy use of javascript "Promises" to route control through the entire app. The source code has some nice examples, but it would be callback spaghetti without it - You can import and export trees to share with your friends ("import tree" and "export tree" commands) - You can build levels from within the app with "build level". The intro diaog should step you through the process - It even supports interactive rebasing! Try it out with "git rebase -i HEAD~3" Git is a fairly complex too that can be explained really well graphically. I never understood what I was doing until I saw diagrams in the git manpages and various books around on the internet. I wanted there to be an interactive form of these diagrams but it didn't exist --- so I built it. 9,000 lines of JS later I have this. There's still some polishing to be done, but I'd love for the community to share their knowledge about different git workflows and different ways to explain git concepts. I tried to make the bar for contributing as low as possible. You can build a level and submit a pull request without even cloning the repo!

nwhitehead 14y ago
Very nice! I worked through all the levels you have and everything worked great, it was a lot of fun. Some notes: I "cheated" and used cherry-pick before it was introduced, not sure if that should or should not be allowed. Sometimes I was frustrated because my graph looked like the goal except for "ghosted" nodes, had to go back and figure out a different way to solve the level the right way. I wished I had an "undo" feature to take back moves rather than resetting everything. Lots more hints would be good, this stuff is hard. Honestly I learned more git in the last 10 minutes than I've learned in a year of using git, or from several hours reading git tutorials.
- xxbondsxx 14y ago
  Wow that's great to hear! Seriously, really glad someone found it useful. That's the entire reason I built it. Levels support a "disable-map" that will prevent certain commands from executing. I somewhat foolishly assume that users only learn commands as I introduce them, but I should go back and lock down some of the levels. Also, I'm working on a way to compare trees without the ghosted nodes --- it's a bit tricky, but if anyone loves graph traversal and would love to help, chime in on github!

r4pha 14y ago

shameless plug: www.srctree.net - Ace editor + git + canvas for viewing commits/branches. I built it about a year ago, mostly for learning and fun. I haven't advertised it a lot but it seems relevant in here. I hope it's not off topic!

THINKBEFORE 14y ago
totally do not understand what this should do. please give some intro...
- r4pha 14y ago
  I guess I need to rethink the whole layout. Under 'tips' there is a small explanation but might still be confusing. There's also a 'see an example' on the bottom, but I guess it's not that helpful either. Someone gave me a nice hint of doing a landing page with explanation and a huge 'start coding' button. I'll do that :)
contingencies 14y ago
Interesting but how to get other code in there is not so clear. Could be useful as an educational tool, with nicer defaults.
- r4pha 14y ago
  I'm not sure I get it. You can start coding and just keeping on commiting and it will handle branching automatically. No doubts that I should make that clear somewhere.
cormacrelf 14y ago
I just wish you could merge and rebase.
- r4pha 14y ago
  That would be one of the next steps. I just released an really simple MVP and got my head around other projects. I'm sure gonna refactor the thing eventually and make some things clearer.

shurcooL 14y ago

Nice stuff. This kind of branching visualisation is highly useful. I'd like to work with that kind of interface. I suppose I should use gitk or something similar? How did you create the branch visualization? Did you use some sort of library for displaying and animating connected nodes, or is it all coded from scratch?

prophetjohn 14y ago
Looks like raphael https://github.com/pcottle/learnGitBranching/tree/master/lib https://github.com/pcottle/learnGitBranching/tree/master/lib
xxbondsxx 14y ago
I had to code it all from scratch unfortunately :-/ I looked at d3.js, arbor.js, and a ton of other libraries but none of them supported the tree layout I had in mind. Apparently visual tree layouts are PhD dissertation topics so there's a wide variety out there I think a lot of educational value is in the animations as well, so it made sense to roll my own. The majority of the code involves all the visual and GUI elements -- re-implementing git (ironically) wasn't too bad!

js-coder 14y ago

Dude, this is epic! Really great work.

g3orge 14y ago

you need to replay the solutions slower...

wildmXranat 14y ago

Since the author mentions that it's not ready for submission and use yet, I won't complain that I didn't know what to do with this demo at first. After reading these comments, it became obvious how great the thing is and going back with that in mind made the app more enjoyable

archgoon 14y ago

This tutorial is great, but it propagates a misconception about git. "A commit in git is a recorded set of changes that you have made" Git commits are _not_ deltas. They are entire snapshots of the repository and a single (optional) pointer to an ancestor commit[1]. Git may handle _compression_ in terms of deltas (see 'Packfiles' in [2]), but logically, a commit should be thought of as equivalent to the state of all files that are being tracked. That difference is that if you were only looking at diffs, commits would be the _edges_ of a graph, rather than a node plus a single edge. This is why rebases change the commit SHAs but not merges (and why merges create a new commit). This is why if you are on a merge branch, 'git checkout HEAD~3' may not bring you to where 'git log' would naively suggest. Version control systems that actually do think of 'commits' as pure 'deltas' are ones such as darcs. A really good, low level explanation, of git is here http://git-scm.com/book/en/Git-Internals-Git-Objects http://git-scm.com/book/en/Git-Internals-Git-Objects (BUG REPORT) The commit created with 'git merge b2' from branch b1 should have HEAD~1 point to the previous head of b1, not b2. (that said, this is a really cool thing. :) I look forward to the author adding support for conflict resolution. ) [1] http://git-scm.com/book/en/Git-Internals-Git-Objects#Commit-Objects http://git-scm.com/book/en/Git-Internals-Git-Objects#Commit-... [2] http://git-scm.com/book/en/Git-Internals-Packfiles http://git-scm.com/book/en/Git-Internals-Packfiles

xxbondsxx 14y ago
Thanks a ton for catching this. I guess there is a distinction to be made -- the compression might use delta's, but a commit specifies the entire state of the repository. It's a tricky line to walk though, because commands like "git show" and "git patch" clearly show the delta-like nature of a single commit. I also don't want newcomers to think that commits are heavy and should be used sparingly. I'm totally down to discuss this on a github issue with you, we could go over the wording. Maybe something like "a commit specifies the entire state of a repository, but is usually stored on disk as a set of changes"? EDIT: moving discussion to: https://github.com/pcottle/learnGitBranching/issues/6 https://github.com/pcottle/learnGitBranching/issues/6 EDIT: fixed in: https://github.com/pcottle/learnGitBranching/commit/168852b293697442ea458a96a9c17c15e87a5594 https://github.com/pcottle/learnGitBranching/commit/168852b2...

devin 14y ago

This is great. Adding this to my list of resources for beginners. The ability to build levels, export trees, etc. makes it even better.

ecoffey 14y ago

This is really really great. Good visualizations of how git works are really awesome and useful, so thanks! That said, the intro lesson introduces commits as exclusively deltas. This isn't accurate, and would probably cause confusion with later concepts. Commits are really snapshots of a tree object (with probably a whole lot of sub trees, and a whole lot of blobs). Since part of the commit meta-data is the parent sha, it's really easy for git to show you the delta, but at it's core git cares about linked snapshots of trees. I am now done being anal retentive :-) thanks again for the great site, excited to see it more fleshed out

xxbondsxx 14y ago
Discussion here, I'm updating as we speak: https://github.com/pcottle/learnGitBranching/issues/6 https://github.com/pcottle/learnGitBranching/issues/6

ExpiredLink 14y ago

I don't see how this could be helpful. Does the author imply that there exists only one branching and merging strategy for any CVS?

Cthulhu_ 14y ago
No? Else the link / project would be called "Learn CVS Branching"

cocoflunchy 14y ago

This is a great tool, thanks so much ! I have trouble understanding the rebase workflow: What is the difference between these two sequences? git checkout -b bugFix git commit -m "fix" git checkout master git commit -m "master stuff" git rebase bugFix git checkout bugFix git rebase master and git checkout -b bugFix git commit -m "fix" git checkout master git commit -m "master stuff" git checkout bugFix git rebase master git checkout master git rebase bugFix Is it just the order of the commits in the final tree that will be different? Or I am missing something else? Instinctively I would tend to do the first one, but that was not what lesson 4 expected...

jedbrown 14y ago
In both cases, the second 'git rebase' is just a fast-forward (moving the ref ahead without modifying the graph). Thus we need only distinguish what happens in the first 'git rebase', which is a different choice of which patch gets rewritten. Note that you can shorten git checkout bugFix git rebase master to git rebase master bugFix
csense 14y ago
Rebase works by discarding commits and replacing them with different commits. If you rebase, then anyone who has the old commits in their repo will have to use git reset --hard to switch to the new branch. In other words, rebase inconveniences all other users of a branch. So you can use it freely on branches that only you work on, but you should be reluctant to use it on branches used by other people -- especially popular branches like "master". If you use your first workflow, the app clearly shows that you discard the commit C3 ("master stuff") and replace it with a different commit C3'. This requires everyone on master to reset. If you use your second workflow, the commit that you're discarding is C2 ("fix") instead. This means that only people who checked out C2 on bugFix need to reset.
- cocoflunchy 14y ago
  Thanks, that makes sense.

Flimm 14y ago

C1' has two meanings, one is the result of a rebase, and one is the result of a revert. I stared at level 2 of "master the rebase, Luke" for a while before I realised this. I think these two things should be have different notations (maybe C1' and C1^-1, or C1' and C1r).

Flimm 14y ago
In fact, I solved that level using only 'git revert' commands, which I don't think was the intended solution. And the displayed solution isn't complete: it asks the user to perform an interactive rebase. (I'm not complaining, just feedback.)
- xxbondsxx 14y ago
  That's a good point. I should just disable revert in all levels except for those related to it. I rarely revert in practice so it's not a huge issue. Showing the concept of a "modified" commit is hard though. That's why I did all the C1' sillyness (like the man pages do). The apostrophes also scale nicely (up to C1'^99) where reverting a reverted rebased commit might make the text too big. EDIT: Fixed, see: https://github.com/pcottle/learnGitBranching/issues/7 https://github.com/pcottle/learnGitBranching/issues/7

alexzhan 14y ago

The back array does not function well.

snip596 14y ago

Awesome visualization, but it seems to deviate from how git works in a few instances. Take "level mixed2" for example. The initial branch checked out was "caption". I did "git rebase -i master" and picked both commits (no re-ordering). That created C2' and C3' which is not correct. C2' wouldn't have been created because it's the same tree as C2 with the same ancestor. I had other issues with that level as well. It seems to be teaching inefficient habits by forcing strange rebases rather than a single one with an "edit" on C2. I understand this might be a limitation on the (really cool) visualization, but maybe those levels shouldn't be included if you can't show the most intuitive way (at least to me) to accomplish the goal. Otherwise, awesome work!

orangethirty 14y ago

I would seriously consider packaging this as an enterprise teaching tool for developers. Companies buy this sort of tools for training. Very good commercial potential here.

xxbondsxx 14y ago
I also spoke to the Github guys about integrating this into their set of training tools (try.github and a few docs), but I think they got caught up with their full time responsibilities because I haven't heard back in a while. I could commercialize it but it deserves to be free!
- polymatter 14y ago
  well, this is seriously awesome - especially if you intend to carry on with it. would you consider a gittip or similar, so I can buy you a coffee?
- orangethirty 14y ago
  You do know that with the license you currently have in there anyone can just sell it, right? You don't have an issue with that?
  - xxbondsxx 14y ago
    I'd be really disappointed if someone added one level and started selling a zip file of the application to enterprises for $400 a pop. That being said, I've heard the GNU license is sometimes too prohibitive (albeit no definitive examples). If you know licenses at all, I'd love some advice
    - orangethirty 14y ago
      $400? This would sell for thousands in the right market. Add in training, and you have a long time gig here. This would even be a great online training business. So many possibilities. Right now, you cant be disappointed if the license allows it. If you have doubts, change it now. In terms of licenses, I'm not really an expert. But you could just roll your own. Just take the one you have right now, and remove what allows people to sell it. Still won't stop some people from doing it, though. For example, I forked your repo. Why? Because its such a nice platform, that I want to learn how it works. I saw that about other 20 people had forked it too. What is stopping them from putting up a website and selling it? Nothing. Nothing at all. Open source is awesome and all. But you have to also be aware that there are a lot of ruthless people out there waiting for programmers like you to put out software like this one under such licensing terms. Its like buying a car, and listing everyone you know as an owner in the title. Can't get mad when they sell it.

aymeric 14y ago

Would be nice to see the solution of a level, to compare it with what we have done (and to find the solution if we are stuck).

xxbondsxx 14y ago
You can type in "show solution" to see the solution for a level (after a prompt). I'll have to add this to some help dialog somewhere... (again I apologize about the discoverability for different commands -- was going to document all this before submitting)
- aymeric 14y ago
  Thanks!

mappum 14y ago

My only criticism is that there a million modals you have to go through, and some are even multi page, adding complexity. I would rather have fewer modals/pages that show more text at once. But overall, this is super handy, great idea :)

mawuli 14y ago

Great work. I recently found a very practical use of Git. I call it the "Poor man's hot code loading". This is a post i just wrote on it http://blog.mawuli.me/2013/02/poor-mans-hot-code-loading-git-branch.html http://blog.mawuli.me/2013/02/poor-mans-hot-code-loading-git...

homosaur 14y ago
I like this, I use Git in this way on my testing server quite often.

joeblau 14y ago

This looks awesome! Thanks for putting this together. It's hard to keep something cool under wraps :)

2mur 14y ago

Awesome. Using some lovely client side tech: backbone, browserify. Going to have to really spend some time looking through the code. Cheers!

arasmussen 14y ago

I found it a bit annoying that the "Alert!" dialogs in the beginning looked like a window but didn't work like one whatsoever (couldn't minimize, close, maximize, or move around). Probably shouldn't make something look like a well-known UI if it doesn't behave like that UI, especially to the point where familiar buttons don't work.

fiatpandas 14y ago

Buggy in Firefox. Stoplight window buttons not correctly placed, and the popups aren't centered-- they just align to the upper left

justplay 14y ago

Great work. Thanks for releasing .

Tomino 14y ago

Awesome work, obviously author has spent a lot of time on this and thought it through. Even with advanced GIT skills, it made me think about few things.

newtang 14y ago

This is really well done. Nice job! Another direction you can go with this is to make a series of Git puzzles. Basically, starting with this diagram A, convert to diagram B in the least number of moves. To be extra useful, these could revolve around common Git pitfalls.

charlieflowers 14y ago
This is a fantastic idea! Just like chess puzzles, only for git. Would be a great deliberate practice tool.
- newtang 14y ago
  Exactly, the chess puzzles are a perfect comparison.

deleted 14y ago

[deleted]

swah 14y ago

I thought I knew enough git, but the other day I was still able to lose my changes... Suppose I'm in master and already modified a file, and now I notice that it would be better to work on a devel branch with those changes, so I could pull upstream changes from master and merge locally. I think I did something like this: git stash git checkout -b devel git stash apply git add file.txt git commit -m "XYZ new changes" git checkout master git fetch git rebase origin/master (to avoid an empty merge, changes upstream were in independent files) git merge devel (to get commit "XYZ") In the end of this, I had lost my changes in file.txt.

happypeter 14y ago

Have tried merging and rebasing, absolutely wonderful!

sleepybrett 14y ago

I worked my way up to branch spaghetti, where I went into the deep end, the solution for it uses commands and concepts not well introduced in the proceeding 'puzzles' (rebase -i)