问题
We have come to git after using SVN for years and at times, I must admit, it is confusing. Take the following example -
- User1 makes a change to a.java and pushes to the remote server.
- User2 makes a change to b.java. He can't push straight away (a deviation from SVN but that is OK). He needs to first pull from remote server, and then push his change to the remote server. This would be shown as a separate merge commit and has been beautifully explained in here on stackoverflow itself
- Now is the interesting part. If we extrapolate this to multiple files, there is a possibility of a conflict with one of those changed by User2. This time, git can't make an auto-commit. User2 would have to resolve the conflicts and then commit this merge.
This is confusing since the user who hasn't made changes to so many files would be skeptical about committing them as part of this merge commit (especially with the SVN background). If this user now just commits the files which he resolved the conflicts for and pushes to the remote, Git stops giving the latest versions of the files that he didn't push. This brings the perception of I lost my work in the rest of the team.
My question after this long story is, why does it do so? Why shouldn't GIT keep the other files at their latest revision? Should git know that the user is not committing all the files that it brought to the user's machine as part of this auto-merge? Could there be a mechanism by which we can avoid making this mistake?
回答1:
First let me clarify that a git pull cannot cause a merge conflict in files that were not touched by a local commit. So a user will only ever have to deal with files he actually touched.
If these merge commits are a problem to you, you should consider switching your work flow. The way to interact with git is not set into stone and there are large differences in established work flows. For instance the PostgreSQL project works with git entirely without any merge commits. On the other hand there is a workflow that uses merge commits in a meaningful way. To obtain a behaviour that resembles the SVN workflow a bit, pass --rebase to git pull, but before doing so, read man git-rebase carefully to understand the implications. Alternatively you can use git stash to pull remote changes before committing, but any of these options just places the conflict resolution step in a different spot.
To examine your last question: Git treats a working tree as a snapshot of your project. If it were mixing newer files with older files, different files would have different versions, a concept that is foreign to git. If you want such a feature, you need to look for e.g. CVS (no joke). There is a tradeoff being made here: Any version control system has to make the decision of either being able to track file moves or being able to track different files in different versions. Git chose the former.
来源：https://stackoverflow.com/questions/22368779/git-merge-branch-master-of-https-bitbucket-org-xxx-yyy