How to Merge files from previous revision number to tip in mercurial? - merge

Suppose I have a revision "6443" however this revision does not have changes which were committed with revision number "6409".
Here to get the changes from "6409" merged with revision "6443" I am thinking of a solution one is get the files from "6409" merge with "6443" and Commit however it would go with new revision number i.e 6444 which I dont want.
Please note here i am trying to merge in the same branch
Is there any other way where I can achieve the same?
Thanks

The DAG you attached shows that a merge is not necessary, as changeset 6409 is a direct descendent of your tip changeset 6443. Thus if the changes of 6409 are not present anymore, there is some intermediate changeset which undoes what 6409 introduced. The right course of action would be to revert or backout that commit which damages the desired changes of changeset 6409.
See also http://hgbook.red-bean.com/read/finding-and-fixing-mistakes.html
This question also basically is a duplicate of
How to force a merge with an ancestor?

Related

Using mercurial why would I ever want to merge without committing?

Perhaps I'm biased from years of svn but why would I ever want to merge with a different branch then make some changes before committing. The hg output itself suggests otherwise:
(branch merge, don't forget to commit)
Dear hg, then why didn't you just do it for me?
Because a merge operation is not guaranteed to produce correct output (automatic merges can use bad heuristics for how to deal with conflicts, manual merges can suffer from human error). Usually, what you will do is the following:
Merge.
Build.
Test.
If the test failed, fix the issue, go back to 2.
Commit.
Mercurial does not suggests otherwise, it 's just reminder: "All merge-related changes stored only on Working Dir, commit results into repository for permanent storing" and doesn't prohibit you to make some additional changes in code before commit.
But separation of tasks (merge and not-related to merge changes - i.e changes not initiated by merge-conflicts) into separate changesets is good idea anyway

Rolling back a merge in TFS2008 with tfpt.exe

I need to roll back a merge operation in TFS2008. The branch will need to be merged at a later date. I know I can use the tfpt.exe rollback operation on the trunk to restore the files modified by the merge, but rollback doesn't modify the merge information so future merges from the branch into the trunk won't restore the changes undone by the rollback. Also, merges from the trunk into the branch will risk overwriting changes in the branch.
I've probably left out quite a bit of necessary information, so I'll update the question as needed.
What is the best way to undo the merge, and still be able to merge all changes in at a later date?
Thanks.
I just tried this doing it manually and when you attempt to merge after after having checked out an older version and then checking in the older version the file is still essentially flagged as already merged. I see the same exact problem when doing it without tfpt- pretty interesting.
So I took a look at the docs and it looks like what you are going to want to do is use /force. I am guessing if you do a tfpt rollback and then run tf merge it will work. If not, try manually rolling back and then running tf merge /force.
/force
Ignores the merge history and
merges the specified changes from the
source into the destination, even if
some or all these changes have been
merged before.
Hope that helps.

How commits are kept in order

Quick question on Mercurial. Suppose my colleague and I both have an up to date copy of trunk. We both make changes, then we both push/pull the changes from each other.
I am guessing Mercurial keeps the changes in order based on the date of the commit (since there is no incrementing revision, just a GUID). So what happens if my computer's date is one day behind and I commit half a day after my colleague. Would my change show up half a day before my colleague's?
#Martijn has your correct answer, but it doesn't seem to be clicking. If this makes anything clear pick his:
The commit times on Mercurial changesets have absolutely nothing to do with how they're merged, interleaved, or combined
Mercurial, and other DVCs, do all history tracking based entirely on the DAG (Directed Acyclic Graph), which means:
the only piece of metadata that matters is the parent or parents of a changeset
Before you commit you can see what the parent of your changeset is going to be by typing hg parents and once you commit you can see it in the hg log.
In your examples if you've pulled your colleague's changesets and updated your working directory to reflect them (hg pull ; hg update) then his or her changeset will be the parent of your changeset. If you haven't pulled/updated to reflect his or her changeset then both of your changesets will have the same parent -- they'll be siblings -- when when they're merged neither will take precedence over the other in any way.
The ordering when you do a hg log is determined by the order in which the changeset arrived in your local repository, and can differ from repo to repo depending on where they've pulled from first -- that's why you can't use the integer numbers shown next to changesets for cross-repo operations -- only the hash is global.
In short the date is never consulted in normal operations and is purely metadata with no more relevance than the author or commit description.
Indeed, your changesets are timestamped (internally stored as seconds-since-the-UNIX-epoch and a timezone offset), and when displaying changeset, they are ordered by timestamp and your changesets will be displayed in the incorrect place as their timestamps are be incorrect. See https://www.mercurial-scm.org/wiki/ChangeSet
This is not really that much of a problem though; timestamps have no bearing on how your changes are merged with those of your colleague. Only the changeset IDs matter here and when merging a common ancestor is used. It'll follow the graph of your changesets down looking for a changeset ID that your colleague also has and then merges your and his changes from the on forward. See https://www.mercurial-scm.org/wiki/Merge
So, merges are not affected, only the display of changesets, where your changesets will be sorted into the wrong location. It'll confuse you and your colleague, but your changes themselves are safe.
The order of changesets is not affected by the timestamp in the changesets. The order is determined solely by the order in which the changesets were created in your local repository.
Mercurial has an append-only architecture so when you pull from another repository, the changesets you pull in are placed after your own changesets, regardless of the timestamps in the new changesets.
The revision numbers (the local integer counter) is just a counter: each new changeset gets the next available revision number. The simple range operator in Mercurial works directly on revisions numbers, and so X:Y means "give me changesets with revision numbers from X to Y (inclusive)". This is not so useful when the revision numbers are based only on the order in which changesets were created or pulled into a repository.
Use X::Y instead, that gives you changesets that are descendants of X and ancestors of Y, i.e., it follows the branches in the history.

Interactive merge with SVN to merge commit by commit

Do you know any tool that support the followings:
eclipse integration (not mandatory)
merge tracking
interactive merge
merging with selecting changesets, but commit them one-by-one to preserve commit comments
So the flow I expect:
picking the source to merge to workspace
choosing revisions to merge
the program would do the merge for the first revision, would pop up conflict resolving if any, and if no conflict it would commit with the original commit comment + merging info with appropiate svn properties
go to next revision.
Do you know such tool?
No, I doubt any tool does this exactly as you describe - why would they when you can a) replicate the functionality by merging 1 revision at a time anyway, b) prefer to make the commit a manual process so the operator can check the merged results. Having merges commit automatically is just slightly optimistic.
You could write such a tool with script - for each revision, merge, fetch original log comment, commit.
Note you don't need to worry about properties as they are merged automatically as part of the merge process.

What am I doing wrong with SVN merging?

When SVN with merge tracking works, it's really nice, I love it. But it keeps getting twisted up. We are using TortoiseSVN. We continuously get the following message:
Error: Reintegrate can only be used if revisions 1234 through 2345 were previously merged from /Trunk to the reintegrate source, but this is not the case
For reference, this is the method we are using:
Create a Branch
Develop in the branch
Occasionally Merge a range of revisions from the Trunk to the Branch
When branch is stable, Reintegrate a branch from the branch to the trunk
Delete the branch
I Merge a range of revisions from the trunk to the branch (leaving the range blank, so it should be all revisions) just prior to the reintegrate operation, so the branch should be properly synced with the trunk.
Right now, the Trunk has multiple SVN merge tracking properties associated with it. Should it? Or should a Reintegrate not add any merge tracking info?
Is there something wrong with our process? This is making SVN unusable - 1 out of every 3 reintegrates forces me to dive in and hack at the merge tracking info.
This problem sometimes happens when a parial merge has been done from trunk to branch in the past. A partial merge is when you perform a merge on the whole tree but only commit part of it. This will give you files in your tree that have mergeinfo data that is out of sync with the rest of the tree.
The --reintegrate error message above should list the files that svn is having a problem with (at least it does in svn 1.6).
You can either:
Merge the problem files manually from trunk to branch, using the range from the error message. Note: you must subtract 1 from the start of the range, so the command you'd run would be:
cd <directory of problem file in branch working copy>
svn merge -r1233:2345 <url of file in trunk>
svn commit
or
If you're certain that the contents of the files in your branch are correct and you just want to mark the files as merged, you could use the --record-only flag to svn merge:
cd <directory of problem file in branch working copy>
svn merge --record-only -r1233:2345 <url of file in trunk>
svn commit
(I think you can use --record-only on the entire tree, but I haven't tried it and you'd have to be absolutely sure that there are no real merges that need to come from trunk)
Bunny hopping might be the solution.
Basically, instead of continuously merging trunk changes into a single branch (branches/foo, let's call it), when you want to pull those changes from trunk:
Copy trunk to a new branch (branches/foo2).
Merge in the changes from the old branch (merge branches/foo into branches/foo2).
Delete the old branch (delete branches/foo).
Your problem is that you're trying to use Reintegrate merge on a branch that has been 'corrupted' by having a 'half merge' already done on it. My advice is to ignore reintegrate and stick to plain on revision merging if this is your workflow.
However, the big reason you get errors is because SVN is performing some checks for you. In this case, if the merge has extra mergeinfo from individual files in there, then svn will throw a wobbly and prevent you from merging - mainly because this case can product errors that you might not notice. This is called a subtree merge in svn reintegrate terminology (read the Reintegrate to the Rescue section, particularly the controversial reintegrate check at the end).
You can stop recording mergeinfo when you perform your intermediary merges, or just leave the branch alone until its ready - then the merge will pick up changes made to trunk. I think you can also byass this check by only ever merging the entire trunk to branch, not individual files thus keeping mergeinfo safe for the final reintegrate at the end.
EDIT:
#randomusername: I think (never looked too closely) at moving is that it falls into the 'partial merge' trap. One cool feature of SVN is that you can do a sparse checkout - only get a partial copy of a tree. When you merge a partial tree in, SVN cannot say that the entire thing was merged as it obviously wasn't, so it records the mergeinfo slightly differently. This doesn't help with reintegrate as the reintegrate has to merge everything back to the trunk, and now it finds that some bits were modified without being merged, so it complains. A move appears kind of the same thing - a piece of the branched tree now appears differently in the mergeinfo than it expects. I would not bother with reintegrate, and stick with the normal revision range merge. Its a nice idea, but it trying to be too many things to too many users in too many different circumstances.
The full story for mergeinfo is here.
I suspect you're not following the merge instructions correctly:
"Now, use svn merge with the --reintegrate option to replicate your branch changes back into the trunk. You'll need a working copy of /trunk. You can get one by doing an svn checkout, dredging up an old trunk working copy from somewhere on your disk, or using svn switch (see the section called “Traversing Branches”). Your trunk working copy cannot have any local edits or contain a mixture of revisions (see the section called “Mixed-revision working copies”). While these are typically best practices for merging anyway, they are required when using the --reintegrate option.
Once you have a clean working copy of the trunk, you're ready to merge your branch back into it:"
I have few problems with merging.