Rebasing in SmartGit
Rebasing is a powerful feature of Git which allows the commit history of branches and commits in a repository to be rearranged.
In SmartGit, there are several ways to initiate a rebase:
- Menu and toolbar: On the Working tree window, select Branch|Rebase to open the Rebase dialog, where you can select the branch to rebase the HEAD onto, or the branch to rebase onto the HEAD, respectively.
You can open this dialog using the Rebase toolbar button, depending on your toolbar settings.
- Branches view: In the Branches view, you can right-click on a branch and select Rebase to rebase your current HEAD onto the selected branch.
- On the Log Graph of the Log window, you can use either of these approaches:
- Option 1: You can perform a rebase by right-clicking on a commit and selecting Rebase from the context-menu.
- Option 2: You can drag and drop commits or refs and then select to rebase in the occurring dialog after the drop.
As with merge and cherry-picking, a Rebasing may fail due to merge conflicts.
When a conflict happens, SmartGit will leave the working tree in rebasing state, allowing you to either resolve the conflicts or to Abort the rebase manually.
In addition, SmartGit provides advanced UI to support interactive rebasing. Please refer to Interactive Rebasing.
Rebase Onto
Rebasing Onto allows the parent commit of an existing commit to be changed.
Rebase Onto operations can be performed from the Log window.
Example : In the below, we’ve made a mistake when starting branch quickfix2. Instead of creating a new branch from main, we’ve accidentally branched off branch quickfix1. As a result, quickfix2 ALSO has all the commits that quickfix1 in its branch, which means that quickfix2 cannot be merged into main independently of quickfix1.
To fix this, we need the quickfix2 branch to start on the main branch instead of the quickfix1 branch.
o q2b [quickfix2]
|
o q2a
/
o q1b [quickfix1]
|
o q1a
/
o A [main]
|
.
To fix the branching, drag the q2a commit onto the A [main] commit. This will result in the intended branching:
o q1b [quickfix1]
|
| o q2b [quickfix2]
| |
o q1b o q2a
\ /
\ /
o A [main]
|
.
Resolving Conflicts
When a merge conflict occurs during Git Rebasing, rebase conflicts differ from regular merge conflicts because the left and right files are swapped in the 3 way merge process.
E.g. when rebasing branch A onto branch B, Git first checks out branch B, then applies all commits from branch A.
If a conflict occurs during the rebase operation, the HEAD of the Working Tree will be left pointing to branch B, so files in the left pane refer to the version in branch B, and the right pane will be Branch A.