We moved the pointer and reset the code back to a previous commit, but it did not delete any commits. You may have noticed that the original chain of commits was still there after we did the reset. Then they can pull a fresh copy after the infringing operation without needing to merge. If you must make changes against code that has already been pushed and is being used by others, consider communicating before you make the changes and give people the chance to merge their changes first. In short, if you rollback, undo, or rewrite the history of a commit chain that others are working with, your colleagues may have a lot more work when they try to merge in changes based on the original chain they pulled. But avoid making changes that rewrite history if the commits have already been pushed to the remote repository and others may be working with them. This brings us to one of the fundamental rules when working with Git in this manner: Making these kinds of changes in your local repository to code you haven't pushed yet is fine. This is because the Git workflow works well for picking up additional commits at the end of a branch, but it can be challenging if a set of commits is no longer seen in the chain when someone resets the branch pointer back. Why would you choose to do a revert over a reset operation? If you have already pushed your chain of commits to the remote repository (where others may have pulled your code and started working with it), a revert is a nicer way to cancel out changes for them. Here are the current contents of the file in the working directory: $ cat If we do a git log now, we'll see a new commit that reflects the contents before the previous commit. # with '#' will be ignored, and an empty message aborts the commit.įigure 3 (below) shows the result after the revert operation is completed. # Please enter the commit message for your changes. This can be done with a git revert command, such as: $ git revert HEADīecause this adds a new commit, Git will prompt for the commit message: Revert "File with three lines" If we add a line to a file in each commit in the chain, one way to get back to the version with only two lines is to reset to that commit, i.e., git reset HEAD~1.Īnother way to end up with the two-line version is to add a new commit that has the third line removed-effectively canceling out that change. The effect is most easily seen by looking at Figure 1 again. Where the reset command moves the branch pointer back in the chain (typically) to "undo" changes, the revert command adds a new commit at the end of the chain to "cancel" changes. The net effect of the git revert command is similar to reset, but its approach is different. Before you use the hard option, be sure that's what you really want to do, since the command overwrites any uncommitted changes. In effect, it resets (clears out) the staging area and overwrites content in the working directory with the content from the commit you reset to. This overwrites any local changes you haven't committed. Using these options can be useful in targeted circumstances such as git reset -hard . These options include: hard to reset the commit being pointed to in the repository, populate the working directory with the contents of the commit, and reset the staging area soft to only reset the pointer in the repository and mixed (the default) to reset the pointer and the staging area. Because of their distinct goals, the two commands are implemented differently: resetting completely removes a changeset, whereas reverting maintains the original changeset and uses a new commit to apply the undo.The git reset command also includes options to update the other parts of your local environment with the contents of the commit where you end up. Whereas reverting is designed to safely undo a public commit, git reset is designed to undo local changes to the Staging Index and Working Directory. Care must be taken when using this tool, as it’s one of the only Git commands that have the potential to lose your work. Commit History is one of the 'three git trees' the other two, Staging Index and Working Directory are not as permanent as Commits. By default, Git is configured to run the garbage collector every 30 days. Git will permanently delete any orphaned commits after it runs the internal garbage collector. These orphaned commits can usually be found and restored using git reflog. Git reset will never delete a commit, however, commits can become 'orphaned' which means there is no direct path from a ref to access them. There is a real risk of losing work with git reset. If git revert is a “safe” way to undo changes, you can think of git reset as the dangerous method.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |