{"rowid": 15, "title": "Git for Grown-ups", "contents": "You are a clever and talented person. You create beautiful designs, or perhaps you have architected a system that even my cat could use. Your peers adore you. Your clients love you. But, until now, you haven\u2019t *&^#^! been able to make Git work. It makes you angry inside that you have to ask your co-worker, again, for that *&^#^! command to upload your work.\n\nIt\u2019s not you. It\u2019s Git. Promise.\n\nYes, this is an article about the popular version control system, Git. But unlike just about every other article written about Git, I\u2019m not going to give you the top five commands that you need to memorize; and I\u2019m not going to tell you all your problems would be solved if only you were using this GUI wrapper or that particular workflow. You see, I\u2019ve come to a grand realization: when we teach Git, we\u2019re doing it wrong.\n\nLet me back up for a second and tell you a little bit about the field of adult education. (Bear with me, it gets good and will leave you feeling both empowered and righteous.) Andragogy, unlike pedagogy, is a learner-driven educational experience. There are six main tenets to adult education: \n\n\n\tAdults prefer to know why they are learning something.\n\tThe foundation of the learning activities should include experience.\n\tAdults prefer to be able to plan and evaluate their own instruction.\n\tAdults are more interested in learning things which directly impact their daily activities.\n\tAdults prefer learning to be oriented not towards content, but towards problems.\n\tAdults relate more to their own motivators than to external ones.\n\n\nNowhere in this list does it include \u201cmemorize the five most popular Git commands\u201d. And yet this is how we teach version control: init, add, commit, branch, push. You\u2019re an expert! Sound familiar? In the hierarchy of learning, memorizing commands is the lowest, or most basic, form of learning. At the peak of learning you are able to not just analyze and evaluate a problem space, but create your own understanding in relation to your existing body of knowledge.\n\n\u201cFine,\u201d I can hear you saying to yourself. \u201cBut I\u2019m here to learn about version control.\u201d Right you are! So how can we use this knowledge to master Git? First of all: I give you permission to use Git as a tool. A tool which you control and which you assign tasks to. A tool like a hammer, or a saw. Yes, your mastery of your tools will shape the kinds of interactions you have with your work, and your peers. But it\u2019s yours to control. Git was written by kernel developers for kernel development. The web world has adopted Git, but it is not a tool designed for us and by us. It\u2019s no Sass, y\u2019know? Git wasn\u2019t developed out of our frustration with managing CSS files in an increasingly complex ecosystem of components and atomic design. So, as you work through the next part of this article, give yourself a bit of a break. We\u2019re in this together, and it\u2019s going to be OK.\n\nWe\u2019re going to do a little activity. We\u2019re going to create your perfect Git cheatsheet.\n\nI want you to start by writing down a list of all the people on your code team. This list may include:\n\n\n\tdevelopers\n\tdesigners\n\tproject managers\n\tclients\n\n\nNext, I want you to write down a list of all the ways you interact with your team. Maybe you\u2019re a solo developer and you do all the tasks. Maybe you only do a few things. But I want you to write down a list of all the tasks you\u2019re actually responsible for. For example, my list looks like this:\n\n\n\twriting code\n\treviewing code\n\tpublishing tested code to your server(s)\n\ttroubleshooting broken code\n\n\nThe next list will end up being a series of boxes in a diagram. But to start, I want you to write down a list of your tools and constraints. This list potentially has a lot of noun-like items and verb-like items:\n\n\n\tcode hosting system (Bitbucket? GitHub? Unfuddle? self-hosted?)\n\tserver ecosystem (dev/staging/live)\n\tautomated testing systems or review gates\n\tautomated build systems (that Jenkins dude people keep referring to)\n\n\nBrilliant! Now you\u2019ve got your actors and your actions, it\u2019s time to shuffle them into a diagram. There are many popular workflow patterns. None are inherently right or wrong; rather, some are more or less appropriate for what you are trying to accomplish.\n\nCentralized workflow\n\nEveryone saves to a single place. This workflow may mean no version control, or a very rudimentary version control system which only ever has a single copy of the work available to the team at any point in time.\n\n \n\nBranching workflow\n\nEveryone works from a copy of the same place, merging their changes into the main copy as their work is completed. Think of the branches as a motorcycle sidecar: they\u2019re along for the ride and probably cannot exist in isolation of the main project for long without serious danger coming to the either the driver or sidecar passenger. Branches are a fundamental concept in version control \u2014 they allow you to work on new features, bug fixes, and experimental changes within a single repository, but without forcing the changes onto others working from the same branch.\n\n \n\nForking workflow\n\nEveryone works from their own, independent repository. A fork is an exact duplicate of a repository that a developer can make their own changes to. It can be kept up to date with additional changes made in other repositories, but it cannot force its changes onto another\u2019s repository. A fork is a complete repository which can use its own workflow strategies. If developers wish to merge their work with the main project, they must make a request of some kind (submit a patch, or a pull request) which the project collaborators may choose to adopt or reject. This workflow is popular for open source projects as it enforces a review process.\n\n \n\nGitflow workflow\n\nA specific workflow convention which includes five streams of parallel coding efforts: master, development, feature branches, release branches, and hot fixes. This workflow is often simplified down to a few elements by web teams, but may be used wholesale by software product teams. The original article describing this workflow was written by Vincent Driessen back in January 2010.\n\n \n\nBut these workflows aren\u2019t about you yet, are they? So let\u2019s make the connections.\n\nFrom the list of people on your team you identified earlier, draw a little circle. Give each of these circles some eyes and a smile. Now I want you to draw arrows between each of these people in the direction that code (ideally) flows. Does your designer create responsive prototypes which are pushed to the developer? Draw an arrow to represent this.\n\nChances are high that you don\u2019t just have people on your team, but you also have some kind of infrastructure. Hopefully you wrote about it earlier. For each of the servers and code repositories in your infrastructure, draw a square. Now, add to your diagram the relationships between the people and each of the machines in the infrastructure. Who can deploy code to the live server? How does it really get there? I bet it goes through some kind of code hosting system, such as GitHub. Draw in those arrows.\n\nBut wait!\n\nThe code that\u2019s on your development machine isn\u2019t the same as the live code. This is where we introduce the concept of a branch in version control. In Git, a repository contains all of the code (sort of). A branch is a fragment of the code that has been worked on in isolation to the other branches within a repository. Often branches will have elements in common. When we compare two (or more) branches, we are asking about the difference (or diff) between these two slivers. Often the master branch is used on production, and the development branch is used on our dev server. The difference between these two branches is the untested code that is not yet deployed.\n\nOn your diagram, see if you can colour-code according to the branch names at each of the locations within your infrastructure. You might find it useful to make a few different copies of the diagram to isolate each of the tasks you need to perform. For example: our team has a peer review process that each branch must go through before it is merged into the shared development branch.\n\nFinally, we are ready to add the Git commands necessary to make sense of the arrows in our diagram. If we are bringing code to our own workstation we will issue one of the following commands: clone (the first time we bring code to our workstation) or pull. Remembering that a repository contains all branches, we will issue the command checkout to switch from one branch to another within our own workstation. If we want to share a particular branch with one of our team mates, we will push this branch back to the place we retrieved it from (the origin). Along each of the arrows in your diagram, write the name of the command you are are going to use when you perform that particular task.\n\n \n\nFrom here, it\u2019s up to you to be selfish. Before asking Git what command it would like you to use, sketch the diagram of what you want. Git is your tool, you are not Git\u2019s tool. Draw the diagram. Communicate your tasks with your team as explicitly as you can. Insist on being a selfish adult learner \u2014 demand that others explain to you, in ways that are relevant to you, how to do the things you need to do today.", "year": "2013", "author": "Emma Jane Westby", "author_slug": "emmajanewestby", "published": "2013-12-04T00:00:00+00:00", "url": "https://24ways.org/2013/git-for-grownups/", "topic": "code"} {"rowid": 31, "title": "Dealing with Emergencies in Git", "contents": "The stockings were hung by the chimney with care,\nIn hopes that version control soon would be there.\n\nThis summer I moved to the UK with my partner, and the onslaught of the Christmas holiday season began around the end of October (October!). It does mean that I\u2019ve had more than a fair amount of time to come up with horrible Git analogies for this article. Analogies, metaphors, and comparisons help the learner hook into existing mental models about how a system works. They only help, however, if the learner has enough familiarity with the topic at hand to make the connection between the old and new information.\n\nLet\u2019s start by painting an updated version of Clement Clarke Moore\u2019s Christmas living room. Empty stockings are hung up next to the fireplace, waiting for Saint Nicholas to come down the chimney and fill them with small treats. Holiday treats are scattered about. A bowl of mixed nuts, the holiday nutcracker, and a few clementines. A string of coloured lights winds its way up an evergreen.\n\nPerhaps a few of these images are familiar, or maybe they\u2019re just settings you\u2019ve seen in a movie. It doesn\u2019t really matter what the living room looks like though. The important thing is to ground yourself in your own experiences before tackling a new subject. Instead of trying to brute-force your way into new information, as an adult learner constantly ask yourself: \u2018What is this like? What does this remind me of? What do I already know that I can use to map out this new territory?\u2019 It\u2019s okay if the map isn\u2019t perfect. As you refine your understanding of a new topic, you\u2019ll outgrow the initial metaphors, analogies, and comparisons.\n\nWith apologies to Mr. Moore, let\u2019s give it a try.\n\nGetting Interrupted in Git\n\nWhen on the roof there arose such a clatter!\n\nYou\u2019re happily working on your software project when all of a sudden there are freaking reindeer on the roof! Whatever you\u2019ve been working on is going to need to wait while you investigate the commotion.\n\nIf you\u2019ve got even a little bit of experience working with Git, you know that you cannot simply change what you\u2019re working on in times of emergency. If you\u2019ve been doing work, you have a dirty working directory and you cannot change branches, or push your work to a remote repository while in this state.\n\nUp to this point, you\u2019ve probably dealt with emergencies by making a somewhat useless commit with a message something to the effect of \u2018switching branches for a sec\u2019. This isn\u2019t exactly helpful to future you, as commits should really contain whole ideas of completed work. If you get interrupted, especially if there are reindeer on the roof, the chances are very high that you weren\u2019t finished with what you were working on.\n\nYou don\u2019t need to make useless commits though. Instead, you can use the stash command. This command allows you to temporarily set aside all of your changes so that you can come back to them later. In this sense, stash is like setting your book down on the side table (or pushing the cat off your lap) so you can go investigate the noise on the roof. You aren\u2019t putting your book away though, you\u2019re just putting it down for a moment so you can come back and find it exactly the way it was when you put it down.\n\nLet\u2019s say you\u2019ve been working in the branch waiting-for-st-nicholas, and now you need to temporarily set aside your changes to see what the noise was on the roof:\n\n$ git stash\n\nAfter running this command, all uncommitted work will be temporarily removed from your working directory, and you will be returned to whatever state you were in the last time you committed your work.\n\nWith the book safely on the side table, and the cat safely off your lap, you are now free to investigate the noise on the roof. It turns out it\u2019s not reindeer after all, but just your boss who thought they\u2019d help out by writing some code on the project you\u2019ve been working on. Bless. Rolling your eyes, you agree to take a look and see what kind of mischief your boss has gotten themselves into this time.\n\nYou fetch an updated list of branches from the remote repository, locate the branch your boss had been working on, and checkout a local copy:\n\n$ git fetch\n$ git branch -r\n$ git checkout -b helpful-boss-branch origin/helpful-boss-branch\n\nYou are now in a local copy of the branch where you are free to look around, and figure out exactly what\u2019s going on.\n\nYou sigh audibly and say, \u2018Okay. Tell me what was happening when you first realised you\u2019d gotten into a mess\u2019 as you look through the log messages for the branch.\n\n$ git log --oneline\n$ git log\n\nBy using the log command you will be able to review the history of the branch and find out the moment right before your boss ended up stuck on your roof.\n\nYou may also want to compare the work your boss has done to the main branch for your project. For this article, we\u2019ll assume the main branch is named master.\n\n$ git diff master\n\nLooking through the commits, you may be able to see that things started out okay but then took a turn for the worse.\n\nChecking out a single commit\n\nUsing commands you\u2019re already familiar with, you can rewind through history and take a look at the state of the code at any moment in time by checking out a single commit, just like you would a branch.\n\nUsing the log command, locate the unique identifier (commit hash) of the commit you want to investigate. For example, let\u2019s say the unique identifier you want to checkout is 25f6d7f.\n\n$ git checkout 25f6d7f\n\nNote: checking out '25f6d7f'.\n\nYou are in 'detached HEAD' state. You can look around,\nmake experimental changes and commit them, and you can\ndiscard any commits you make in this state without\nimpacting any branches by performing another checkout.\n\nIf you want to create a new branch to retain commits you create, you may do so (now or later) by using @-b@ with the checkout command again. Example:\n\n$ git checkout -b new_branch_name\n\nHEAD is now at 25f6d7f... Removed first paragraph.\n\nThis is usually where people start to panic. Your boss screwed something up, and now your HEAD is detached. Under normal circumstances, these words would be a very good reason to panic.\n\nTake a deep breath. Nothing bad is going to happen. Being in a detached HEAD state just means you\u2019ve temporarily disconnected from a known chain of events. In other words, you\u2019re currently looking at the middle of a story (or branch) about what happened \u2013 and you\u2019re not at the endpoint for this particular story.\n\nGit allows you to view the history of your repository as a timeline (technically it\u2019s a directed acyclic graph). When you make commits which are not associated with a branch, they are essentially inaccessible once you return to a known branch. If you make commits while you\u2019re in a detached HEAD state, and then try to return to a known branch, Git will give you a warning and tell you how to save your work.\n\n$ git checkout master\n\nWarning: you are leaving 1 commit behind, not connected to\nany of your branches:\n\n 7a85788 Your witty holiday commit message.\n\nIf you want to keep them by creating a new branch, this may be a good time to do so with:\n\n$ git branch new_branch_name 7a85788\n\nSwitched to branch 'master'\nYour branch is up-to-date with 'origin/master'.\n\nSo, if you want to save the commits you\u2019ve made while in a detached HEAD state, you simply need to put them on a new branch.\n\n$ git branch saved-headless-commits 7a85788\n\nWith this trick under your belt, you can jingle around in history as much as you\u2019d like. It\u2019s not like sliding around on a timeline though. When you checkout a specific commit, you will only have access to the history from that point backwards in time. If you want to move forward in history, you\u2019ll need to move back to the branch tip by checking out the branch again.\n\n$ git checkout helpful-boss-branch\n\nYou\u2019re now back to the present. Your HEAD is now pointing to the endpoint of a known branch, and so it is no longer detached. Any changes you made while on your adventure are safely stored in a new branch, assuming you\u2019ve followed the instructions Git gave you. That wasn\u2019t so scary after all, now, was it?\n\nBack to our reindeer problem.\n\nIf your boss is anything like the bosses I\u2019ve worked with, chances are very good that at least some of their work is worth salvaging. Depending on how your repository is structured, you\u2019ll want to capture the good work using one of several different methods.\n\nBack in the living room, we\u2019ll use our bowl of nuts to illustrate how you can rescue a tiny bit of work.\n\nSaving just one commit\n\nAbout that bowl of nuts. If you\u2019re like me, you probably had some favourite kinds of nuts from an assorted collection. Walnuts were generally the most satisfying to crack open. So, instead of taking the entire bowl of nuts and dumping it into a stocking (merging the stocking and the bowl of nuts), we\u2019re just going to pick out one nut from the bowl. In Git terms, we\u2019re going to cherry-pick a commit and save it to another branch.\n\nFirst, checkout the main branch for your development work. From this branch, create a new branch where you can copy the changes into.\n\n$ git checkout master\n$ git checkout -b rescue-the-boss\n\nFrom your boss\u2019s branch, helpful-boss-branch locate the commit you want to keep.\n\n$ git log --oneline helpful-boss-branch\n\nLet\u2019s say the commit ID you want to keep is e08740b. From your rescue branch, use the command cherry-pick to copy the changes into your current branch.\n\n$ git cherry-pick e08740b\n\nIf you review the history of your current branch again, you will see you now also have the changes made in the commit in your boss\u2019s branch.\n\nAt this point you might need to make a few additional fixes to help your boss out. (You\u2019re angling for a bonus out of all this. Go the extra mile.) Once you\u2019ve made your additional changes, you\u2019ll need to add that work to the branch as well.\n\n$ git add [filename(s)]\n$ git commit -m \"Building on boss's work to improve feature X.\"\n\nGo ahead and test everything, and make sure it\u2019s perfect. You don\u2019t want to introduce your own mistakes during the rescue mission!\n\nUploading the fixed branch\n\nThe next step is to upload the new branch to the remote repository so that your boss can download it and give you a huge bonus for helping you fix their branch.\n\n$ git push -u origin rescue-the-boss\n\nCleaning up and getting back to work\n\nWith your boss rescued, and your bonus secured, you can now delete the local temporary branches.\n\n$ git branch --delete rescue-the-boss\n$ git branch --delete helpful-boss-branch\n\nAnd settle back into your chair to wait for Saint Nicholas with your book, your branch, and possibly your cat.\n\n$ git checkout waiting-for-st-nicholas\n$ git stash pop\n\nYour working directory has been returned to exactly the same state you were in at the beginning of the article.\n\nHaving fun with analogies\n\nI\u2019ve had a bit of fun with analogies in this article. But sometimes those little twists on ideas can really help someone pick up a new idea (git stash: it\u2019s like when Christmas comes around and everyone throws their fashion sense out the window and puts on a reindeer sweater for the holiday party; or git bisect: it\u2019s like trying to find that one broken light on the string of Christmas lights). It doesn\u2019t matter if the analogy isn\u2019t perfect. It\u2019s just a way to give someone a temporary hook into a concept in a way that makes the concept accessible while the learner becomes comfortable with it. As the learner\u2019s comfort increases, the analogies can drop away, making room for the technically correct definition of how something works.\n\nOr, if you\u2019re like me, you can choose to never grow old and just keep mucking about in the analogies. I\u2019d argue it\u2019s a lot more fun to play with a string of Christmas lights and some holiday cheer than a directed acyclic graph anyway.", "year": "2014", "author": "Emma Jane Westby", "author_slug": "emmajanewestby", "published": "2014-12-02T00:00:00+00:00", "url": "https://24ways.org/2014/dealing-with-emergencies-in-git/", "topic": "code"} {"rowid": 52, "title": "Git Rebasing: An Elfin Workshop Workflow", "contents": "This year Santa\u2019s helpers have been tasked with making a garland. It\u2019s a pretty simple task: string beads onto yarn in a specific order. When the garland reaches a specific length, add it to the main workshop garland. Each elf has a specific sequence they\u2019re supposed to chain, which is given to them via a work order. (This is starting to sound like one of those horrible calculus problems. I promise it isn\u2019t. It\u2019s worse; it\u2019s about Git.)\nFor the most part, the system works really well. The elves are able to quickly build up a shared chain because each elf specialises on their own bit of garland, and then links the garland together. Because of this they\u2019re able to work independently, but towards the common goal of making a beautiful garland.\nAt first the elves are really careful with each bead they put onto the garland. They check with one another before merging their work, and review each new link carefully. As time crunches on, the elves pour a little more cheer into the eggnog cooler, and the quality of work starts to degrade. Tensions rise as mistakes are made and unkind words are said. The elves quickly realise they\u2019re going to need a system to change the beads out when mistakes are made in the chain.\nThe first common mistake is not looking to see what the latest chain is that\u2019s been added to the main garland. The garland is huge, and it sits on a roll in one of the corners of the workshop. It\u2019s a big workshop, so it is incredibly impractical to walk all the way to the roll to check what the last link is on the chain. The elves, being magical, have set up a monitoring system that allows them to keep a local copy of the main garland at their workstation. It\u2019s an imperfect system though, so the elves have to request a manual refresh to see the latest copy. They can request a new copy by running the command\ngit pull --rebase=preserve\n(They found that if they ran git pull on its own, they ended up with weird loops of extra beads off the main garland, so they\u2019ve opted to use this method.) This keeps the shared garland up to date, which makes things a lot easier. A visualisation of the rebase process is available.\nThe next thing the elves noticed is that if they worked on the main workshop garland, they were always running into problems when they tried to share their work back with the rest of the workshop. It was fine if they were working late at night by themselves, but in the middle of the day, it was horrible. (I\u2019ve been asked not to talk about that time the fight broke out.) Instead of trying to share everything on their local copy of the main garland, the elves have realised it\u2019s a lot easier to work on a new string and then knot this onto the main garland when their pattern repeat is finished. They generate a new string by issuing the following commands:\ngit checkout master\ngit checkout -b 1234_pattern-name\n1234 represents the work order number and pattern-name describes the pattern they\u2019re adding. Each bead is then added to the new link (git add bead.txt) and locked into place (git commit). Each elf repeats this process until the sequence of beads described in the work order has been added to their mini garland.\nTo combine their work with the main garland, the elves need to make a few decisions. If they\u2019re making a single strand, they issue the following commands:\ngit checkout master\ngit merge --ff-only 1234_pattern-name\nTo share their work they publish the new version of the main garland to the workshop spool with the command git push origin master.\nSometimes this fails. Sharing work fails because the workshop spool has gotten new links added since the elf last updated their copy of the main workshop spool. This makes the elves both happy and sad. It makes them happy because it means the other elves have been working too, but it makes them sad because they now need to do a bit of extra work to close their work order. \nTo update the local copy of the workshop spool, the elf first unlinks the chain they just linked by running the command:\ngit reset --merge ORIG_HEAD\nThis works because the garland magic notices when the elves are doing a particularly dangerous thing and places a temporary, invisible bookmark to the last safe bead in the chain before the dangerous thing happened. The garland no longer has the elf\u2019s work, and can be updated safely. The elf runs the command git pull --rebase=preserve and the changes all the other elves have made are applied locally.\nWith these new beads in place, the elf now has to restring their own chain so that it starts at the right place. To do this, the elf turns back to their own chain (git checkout 1234_pattern-name) and runs the command git rebase master. Assuming their bead pattern is completely unique, the process will run and the elf\u2019s beads will be restrung on the tip of the main workshop garland.\nSometimes the magic fails and the elf has to deal with merge conflicts. These are kind of annoying, so the elf uses a special inspector tool to figure things out. The elf opens the inspector by running the command git mergetool to work through places where their beads have been added at the same points as another elf\u2019s beads. Once all the conflicts are resolved, the elf saves their work, and quits the inspector. They might need to do this a few times if there are a lot of new beads, so the elf has learned to follow this update process regularly instead of just waiting until they\u2019re ready to close out their work order.\nOnce their link is up to date, the elf can now reapply their chain as before, publish their work to the main workshop garland, and close their work order:\ngit checkout master\ngit merge --ff-only 1234_pattern-name\ngit push origin master\nGenerally this process works well for the elves. Sometimes, though, when they\u2019re tired or bored or a little drunk on festive cheer, they realise there\u2019s a mistake in their chain of beads. Fortunately they can fix the beads without anyone else knowing. These tools can be applied to the whole workshop chain as well, but it causes problems because the magic assumes that elves are only ever adding to the main chain, not removing or reordering beads on the fly. Depending on where the mistake is, the elf has a few different options.\nLet\u2019s pretend the elf has a sequence of five beads she\u2019s been working on. The work order says the pattern should be red-blue-red-blue-red.\n\nIf the sequence of beads is wrong (for example, blue-blue-red-red-red), the elf can remove the beads from the chain, but keep the beads in her workstation using the command git reset --soft HEAD~5.\n\nIf she\u2019s been using the wrong colours and the wrong pattern (for example, green-green-yellow-yellow-green), she can remove the beads from her chain and discard them from her workstation using the command git reset --hard HEAD~5.\n\nIf one of the beads is missing (for example, red-blue-blue-red), she can restring the beads using the first method, or she can use a bit of magic to add the missing bead into the sequence.\n\nUsing a tool that\u2019s a bit like orthoscopic surgery, she first selects a sequence of beads which contains the problem. A visualisation of this process is available.\nStart the garland surgery process with the command:\ngit rebase --interactive HEAD~4\nA new screen comes up with the following information (the oldest bead is on top):\npick c2e4877 Red bead\npick 9b5555e Blue bead\npick 7afd66b Blue bead\npick e1f2537 Red bead\nThe elf adjusts the list, changing \u201cpick\u201d to \u201cedit\u201d next to the first blue bead:\npick c2e4877 Red bead\nedit 9b5555e Blue bead\npick 7afd66b Blue bead\npick e1f2537 Red bead\nShe then saves her work and quits the editor. The garland magic has placed her back in time at the moment just after she added the first blue bead.\n\nShe needs to manually fix up her garland to add the new red bead. If the beads were files, she might run commands like vim beads.txt and edit the file to make the necessary changes.\nOnce she\u2019s finished her changes, she needs to add her new bead to the garland (git add --all) and lock it into place (git commit). This time she assigns the commit message \u201cRed bead \u2013 added\u201d so she can easily find it.\n\nThe garland magic has replaced the bead, but she still needs to verify the remaining beads on the garland. This is a mostly automatic process which is started by running the command git rebase --continue.\nThe new red bead has been assigned a position formerly held by the blue bead, and so the elf must deal with a merge conflict. She opens up a new program to help resolve the conflict by running git mergetool.\n\nShe knows she wants both of these beads in place, so the elf edits the file to include both the red and blue beads.\n\nWith the conflict resolved, the elf saves her changes and quits the mergetool.\nBack at the command line, the elf checks the status of her work using the command git status.\nrebase in progress; onto 4a9cb9d\nYou are currently rebasing branch '2_RBRBR' on '4a9cb9d'.\n (all conflicts fixed: run \"git rebase --continue\")\n\nChanges to be committed:\n (use \"git reset HEAD ...\" to unstage)\n\n modified: beads.txt\n\nUntracked files:\n (use \"git add ...\" to include in what will be committed)\n\n beads.txt.orig\nShe removes the file added by the mergetool with the command rm beads.txt.orig and commits the edits she just made to the bead file using the commands:\ngit add beads.txt\ngit commit --message \"Blue bead -- resolved conflict\"\n\nWith the conflict resolved, the elf is able to continue with the rebasing process using the command git rebase --continue. There is one final conflict the elf needs to resolve. Once again, she opens up the visualisation tool and takes a look at the two conflicting files.\n\nShe incorporates the changes from the left and right column to ensure her bead sequence is correct.\n\nOnce the merge conflict is resolved, the elf saves the file and quits the mergetool. Once again, she cleans out the backup file added by the mergetool (rm beads.txt.orig) and commits her changes to the garland:\ngit add beads.txt\ngit commit --message \"Red bead -- resolved conflict\"\nand then runs the final verification steps in the rebase process (git rebase --continue).\n\nThe verification process runs through to the end, and the elf checks her work using the command git log --oneline.\n9269914 Red bead -- resolved conflict\n4916353 Blue bead -- resolved conflict\naef0d5c Red bead -- added\n9b5555e Blue bead\nc2e4877 Red bead\nShe knows she needs to read the sequence from bottom to top (the oldest bead is on the bottom). Reviewing the list she sees that the sequence is now correct.\nSometimes, late at night, the elf makes new copies of the workshop garland so she can play around with the bead sequencer just to see what happens. It\u2019s made her more confident at restringing beads when she\u2019s found real mistakes. And she doesn\u2019t mind helping her fellow elves when they run into trouble with their beads. The sugar cookies they leave her as thanks don\u2019t hurt either. If you would also like to play with the bead sequencer, you can get a copy of the branches the elf worked.\n\nOur lessons from the workshop:\n\nBy using rebase to update your branches, you avoid merge commits and keep a clean commit history.\nIf you make a mistake on one of your local branches, you can use reset to take commits off your branch. If you want to save the work, but uncommit it, add the parameter --soft. If you want to completely discard the work, use the parameter, --hard.\nIf you have merged working branch changes to the local copy of your master branch and it is preventing you from pushing your work to a remote repository, remove these changes using the command reset with the parameter --merge ORIG_HEAD before updating your local copy of the remote master branch.\nIf you want to make a change to work that was committed a little while ago, you can use the command rebase with the parameter --interactive. You will need to include how many commits back in time you want to review.", "year": "2015", "author": "Emma Jane Westby", "author_slug": "emmajanewestby", "published": "2015-12-07T00:00:00+00:00", "url": "https://24ways.org/2015/git-rebasing/", "topic": "code"}