You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
210 lines
7.0 KiB
210 lines
7.0 KiB
git-rerere(1) |
|
============= |
|
|
|
NAME |
|
---- |
|
git-rerere - Reuse recorded resolution of conflicted merges |
|
|
|
SYNOPSIS |
|
-------- |
|
'git rerere' ['clear'|'diff'|'status'|'gc'] |
|
|
|
DESCRIPTION |
|
----------- |
|
|
|
In a workflow employing relatively long lived topic branches, |
|
the developer sometimes needs to resolve the same conflicts over |
|
and over again until the topic branches are done (either merged |
|
to the "release" branch, or sent out and accepted upstream). |
|
|
|
This command assists the developer in this process by recording |
|
conflicted automerge results and corresponding hand resolve results |
|
on the initial manual merge, and applying previously recorded |
|
hand resolutions to their corresponding automerge results. |
|
|
|
[NOTE] |
|
You need to set the configuration variable rerere.enabled to |
|
enable this command. |
|
|
|
|
|
COMMANDS |
|
-------- |
|
|
|
Normally, 'git-rerere' is run without arguments or user-intervention. |
|
However, it has several commands that allow it to interact with |
|
its working state. |
|
|
|
'clear':: |
|
|
|
This resets the metadata used by rerere if a merge resolution is to be |
|
aborted. Calling 'git-am [--skip|--abort]' or 'git-rebase [--skip|--abort]' |
|
will automatically invoke this command. |
|
|
|
'diff':: |
|
|
|
This displays diffs for the current state of the resolution. It is |
|
useful for tracking what has changed while the user is resolving |
|
conflicts. Additional arguments are passed directly to the system |
|
'diff' command installed in PATH. |
|
|
|
'status':: |
|
|
|
Like 'diff', but this only prints the filenames that will be tracked |
|
for resolutions. |
|
|
|
'gc':: |
|
|
|
This prunes records of conflicted merges that |
|
occurred a long time ago. By default, unresolved conflicts older |
|
than 15 days and resolved conflicts older than 60 |
|
days are pruned. These defaults are controlled via the |
|
`gc.rerereunresolved` and `gc.rerereresolved` configuration |
|
variables respectively. |
|
|
|
|
|
DISCUSSION |
|
---------- |
|
|
|
When your topic branch modifies an overlapping area that your |
|
master branch (or upstream) touched since your topic branch |
|
forked from it, you may want to test it with the latest master, |
|
even before your topic branch is ready to be pushed upstream: |
|
|
|
------------ |
|
o---*---o topic |
|
/ |
|
o---o---o---*---o---o master |
|
------------ |
|
|
|
For such a test, you need to merge master and topic somehow. |
|
One way to do it is to pull master into the topic branch: |
|
|
|
------------ |
|
$ git checkout topic |
|
$ git merge master |
|
|
|
o---*---o---+ topic |
|
/ / |
|
o---o---o---*---o---o master |
|
------------ |
|
|
|
The commits marked with `*` touch the same area in the same |
|
file; you need to resolve the conflicts when creating the commit |
|
marked with `{plus}`. Then you can test the result to make sure your |
|
work-in-progress still works with what is in the latest master. |
|
|
|
After this test merge, there are two ways to continue your work |
|
on the topic. The easiest is to build on top of the test merge |
|
commit `{plus}`, and when your work in the topic branch is finally |
|
ready, pull the topic branch into master, and/or ask the |
|
upstream to pull from you. By that time, however, the master or |
|
the upstream might have been advanced since the test merge `{plus}`, |
|
in which case the final commit graph would look like this: |
|
|
|
------------ |
|
$ git checkout topic |
|
$ git merge master |
|
$ ... work on both topic and master branches |
|
$ git checkout master |
|
$ git merge topic |
|
|
|
o---*---o---+---o---o topic |
|
/ / \ |
|
o---o---o---*---o---o---o---o---+ master |
|
------------ |
|
|
|
When your topic branch is long-lived, however, your topic branch |
|
would end up having many such "Merge from master" commits on it, |
|
which would unnecessarily clutter the development history. |
|
Readers of the Linux kernel mailing list may remember that Linus |
|
complained about such too frequent test merges when a subsystem |
|
maintainer asked to pull from a branch full of "useless merges". |
|
|
|
As an alternative, to keep the topic branch clean of test |
|
merges, you could blow away the test merge, and keep building on |
|
top of the tip before the test merge: |
|
|
|
------------ |
|
$ git checkout topic |
|
$ git merge master |
|
$ git reset --hard HEAD^ ;# rewind the test merge |
|
$ ... work on both topic and master branches |
|
$ git checkout master |
|
$ git merge topic |
|
|
|
o---*---o-------o---o topic |
|
/ \ |
|
o---o---o---*---o---o---o---o---+ master |
|
------------ |
|
|
|
This would leave only one merge commit when your topic branch is |
|
finally ready and merged into the master branch. This merge |
|
would require you to resolve the conflict, introduced by the |
|
commits marked with `*`. However, this conflict is often the |
|
same conflict you resolved when you created the test merge you |
|
blew away. 'git-rerere' helps you resolve this final |
|
conflicted merge using the information from your earlier hand |
|
resolve. |
|
|
|
Running the 'git-rerere' command immediately after a conflicted |
|
automerge records the conflicted working tree files, with the |
|
usual conflict markers `<<<<<<<`, `=======`, and `>>>>>>>` in |
|
them. Later, after you are done resolving the conflicts, |
|
running 'git-rerere' again will record the resolved state of these |
|
files. Suppose you did this when you created the test merge of |
|
master into the topic branch. |
|
|
|
Next time, after seeing the same conflicted automerge, |
|
running 'git-rerere' will perform a three-way merge between the |
|
earlier conflicted automerge, the earlier manual resolution, and |
|
the current conflicted automerge. |
|
If this three-way merge resolves cleanly, the result is written |
|
out to your working tree file, so you do not have to manually |
|
resolve it. Note that 'git-rerere' leaves the index file alone, |
|
so you still need to do the final sanity checks with `git diff` |
|
(or `git diff -c`) and 'git-add' when you are satisfied. |
|
|
|
As a convenience measure, 'git-merge' automatically invokes |
|
'git-rerere' upon exiting with a failed automerge and 'git-rerere' |
|
records the hand resolve when it is a new conflict, or reuses the earlier hand |
|
resolve when it is not. 'git-commit' also invokes 'git-rerere' |
|
when committing a merge result. What this means is that you do |
|
not have to do anything special yourself (besides enabling |
|
the rerere.enabled config variable). |
|
|
|
In our example, when you do the test merge, the manual |
|
resolution is recorded, and it will be reused when you do the |
|
actual merge later with the updated master and topic branch, as long |
|
as the recorded resolution is still applicable. |
|
|
|
The information 'git-rerere' records is also used when running |
|
'git-rebase'. After blowing away the test merge and continuing |
|
development on the topic branch: |
|
|
|
------------ |
|
o---*---o-------o---o topic |
|
/ |
|
o---o---o---*---o---o---o---o master |
|
|
|
$ git rebase master topic |
|
|
|
o---*---o-------o---o topic |
|
/ |
|
o---o---o---*---o---o---o---o master |
|
------------ |
|
|
|
you could run `git rebase master topic`, to bring yourself |
|
up-to-date before your topic is ready to be sent upstream. |
|
This would result in falling back to a three-way merge, and it |
|
would conflict the same way as the test merge you resolved earlier. |
|
'git-rerere' will be run by 'git-rebase' to help you resolve this |
|
conflict. |
|
|
|
|
|
Author |
|
------ |
|
Written by Junio C Hamano <gitster@pobox.com> |
|
|
|
GIT |
|
--- |
|
Part of the linkgit:git[1] suite
|
|
|