Add more issues and their respective solutions in the 'Common Issues' section of gitfaq. Signed-off-by: Shourya Shukla <shouryashukla.oo@xxxxxxxxx> --- Documentation/gitfaq.txt | 104 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) diff --git a/Documentation/gitfaq.txt b/Documentation/gitfaq.txt index 1cf83df118..fc261cbbf5 100644 --- a/Documentation/gitfaq.txt +++ b/Documentation/gitfaq.txt @@ -223,6 +223,110 @@ a file checked into the repository which is a template or set of defaults which can then be copied alongside and modified as appropriate. This second, modified file is usually ignored to prevent accidentally committing it. +[[rebasing-and-merging]] +How do I know when to merge or rebase?:: + Rebasing and merging two entirely different concepts with different utiilites. + In Git terms, rebasing means to place changes made in one branch over another branch + (called base, hence the term, rebase). The commit history of the branch wanting to rebase + get placed over the branch on the receiving end and it appears as if those changes took + place in the receiving branch itself. Merging, as the name suggests, merges the latest + commit of one branch onto the recent branch, making this combination appear as one separate + commit. ++ +Now that we have an idea of the key differences between merging and rebasing, we can look at the +circumstances when we would want to perform them. Generally, merging is preferred when one desires +to create a new feature, perform its integration testing with the original codebase, and finally +integrate it if all tests are passed. One would choose to create a separate branch for this purpose +and maybe dissolve it when the merge is done. ++ +One might want to perform a rebase when they intend to retain the changes made in a separate branch +into their original branch. In that case, a rebase would place the former changes onto the commit tree +of the latter. ++ +As an additional tip, one can use interactive rebasing, `git rebase -i`, to perform rebasing +using a text editor GUI (the value of $GIT_EDITOR). Interactive rebase is an excellent utility +to perform various functions such as editing commit messages, dropping/squashing commits, editing +commits, etc., all in one package. + +[[files-in-.gitignore-are-tracked]] +I asked Git to ignore various files, yet they show up as changes in my staging area:: + One uses '.gitignore' to ignore files from getting tracked in the working tree. This ignores + the aforementioned files for the whole lifetime of the project unless they area removed from + the '.gitignore'. Consequently, `git add` does not list these files as 'modified' even if any + change was made in them and `git status` does not bother to track the changes in these files + either. + + But, '.gitignore' will only ignore the files which were not a part of the repository when they + were mentioned in the it. Hence, addition of a file to '.gitignore' after it was added to the + working tree will have no effect and Git will keep tracking them. To amend this mistake, i.e., + to untrack and completely ignore a tracked file, one has to use `git rm --cached <file>` to + remove the file from the staging area(i.e. the cache) and not from the repository(presuming + the file has been added in the 'gitignore'). This will hence make our file behave exactly like + we described in the paragraph above. + +[[changing-remote-of-the-repository]] +I want to change the remote of my repository. How do I do that?:: + A remote is an identifier for a location to which Git pushes your changes as well as fetches + any new changes(if any). There might be different circumstances in which one might need to change + the remote: + + 1. One might want to update the url of their remote; in that case, the command to use is, + `git remote set-url <name> <newurl>`. + + 2. One might want to have two different remotes for fetching and pushing; this generally + happens in case of triangular workflows. In this case, it is advisable to create a + separate remote just for fetching/pushing. But, another way can be to change the push + url using the `--push` option in the `git set-url` command. + +[[fetching-and-pulling]] +How do I know if I want to do a fetch or a pull?:: + A fetch brings in the latest changes made upstream(i.e. the remote repository we are working on). + This allows us to inspect the changes made upstream and integrate all those changes(iff we want to) + or only cherry pick certain changes. Fetching does not have any immediate effects on the local + repository. + + A pull is a wrapper for a fetch and merge. This means that doing a `git pull` will not only fetch the + changes made upstream but integrate them as well with our local repository. The merge may go smoothly + or have merge conflicts depending on the case. A pull does not allow you to review any changes made + upstream but rather merge those changes on their own. ++ +This is the reason why it is sometimes advised to fetch the changes first and then merge them accordingly +because not every change might be of utility to the user. + +[[checking-out]] +What is checking out a commit/branch? How do I perform one?:: + In Git terminology, a 'checkout' serves three purposes, namely: + + 1. Go to another commit; I would be "checking out" to that commit and enter a "detached HEAD" + state, meaning, that the "pointer" called HEAD which tells me where I am right now in my + working tree is not where it generally should be, i.e., referring to a named branch(say, master). + Instead the aforementioned pointer is referring to the specified commit. I can now work upon the + checked out commit and make any changes or just inspect the files at that state. + + 2. Go to a different version of a particular file; let's say I want to go to a particular version + of a file in my working tree. I can again "checkout" to that particular version(i.e., going to a + particular commit where certain changes were made). This can be done by entering the SHA1 of the + commit in question. + + 3. Go to another branch or create another branch; I would be "checking out" to another tree + in my local repository. One might expect to enter a detached HEAD here as well but in fact + does not. This is because HEAD would point to the tip of the checked out branch, something + which is not a characteristic of a detached HEAD. ++ +To checkout to a commit, one can either pass the SHA1 of the commit to be checked out or a reference to it w.r.t. +the HEAD. To checkout to a particular version of a file, one can use `git checkout <SHA1/reference> <file>`. +To checkout to an already existing branch, one should use `git checkout <branch-name>`. To simultaneously create +and checkout to a branch, one can use the `-b` option in the aforementioned command. ++ +One can observe how versatile the checkout command is, yet due to simplify things even further, two commands were +introduced in version 2.23 of Git so as to break down the functionalities of `git checkout` and make it learning +the command easier for a beginner. The commands being `git switch` and `git restore`. ++ +`git restore` combines the first two features of the checkout as well as functionalities of `git reset` and `git revert` +at one place so as to improve the functionality of the command. ++ +`git switch` perfoms the third functionality of the `git checkout` command, i.e., manipulating branches(creation). + Hooks ----- -- 2.20.1
