There is a commit in my hg repository with hash 123abc. This is the last commit I made in the repo. When I run hg diff --from 123abc, I see no output. When I run hg log --graph, I see an # next to 123abc.
In Git this commit would be called "HEAD". I'm not sure what it's called in Mercurial. It is not the "tip", because I pulled other changes after the last time I committed (and hg log -r tip shows commit 456def).
What is this commit/head called?
Mercurial calls this the "parent" or the "parent revision of the working directory", and you can see it by running hg parent, hg id, or hg summary.
You can refer to it as . with the hg log command:
hg log -r . # show the commit message for the parent
If 123abc has no children, then it is a "head".
A head is a changeset with no child changesets. The tip is the most
recently changed head. Other heads are recent pulls into a repository
that have not yet been merged.
(https://www.mercurial-scm.org/wiki/Head)
Regardless whether the current working directory derives from a head or a non-head, I would refer to the commit that precedes it as the "working directory parent" changeset or commit. (That may just be the term my team uses - not sure it is "official".)
The parent may be visible in a GUI tool (like Tortoise) or you can get it using hg parent.
Based on the statements about 456def I'm a little confused whether it has no children, or not? (Maybe update the question to clarify / add more detail)
Related
Given a checkout of a Mercurial repository and a filename. How does one determine the last commit that changed that file? Unlike git, care must be taken with branches. The intended semantic here is to follow the history of the branch. Where branches fork from other branches, follow parent branches.
Non-solutions:
shows commits from unmerged branches
hg log -l 1 filename
empty output if the file remains unchanged after branch creation
hg log -l 1 -b . filename
Arguably, this question highlights misuse of branches and bookmarks should be used instead. However that may be, existing history necessiates taking branches into account.
The -f flag tells hg log to follow history of the current or selected changeset, so this should find the first change of a file without looking at changesets that aren't direct ancestors:
hg log -f -l 1 filename
Is there a way to edit a commit message in Mercurial on a commit after other commits have occured using TortoiseHg? I've read these posts:
How to edit incorrect commit message in Mercurial?
Mercurial: how to amend the last commit?
and have been able to update a "regular" commit message when it is the latest commit on a branch (using TortoiseHg). However, I haven't been able to figure out how to edit a commit message when other commits have occurred after the one I want to edit. It always edits the last commit.
Based on Ed Cottrell's comment, I did a test where I made two commits without pushing to the central repo, and I still have the same issue - only the last commit message can be edited.
EDIT: I should clarify that I am looking to update a changeset that has been pushed.
Histedit extension (bundled with TortoiseHG now) has a mess command for changing the commit message of historical changesets.
Unfortunately, this command is not supported by the TortoiseHG GUI so you need to run the command from command line.
As long as the change in question is local and hasn't been pushed anywhere, it is possible.
The commit message is used to compute the globally unique hash id that is used for all repositories to determine whether or not they already have a changeset. If you change the commit message, you change the unique hash id and every repo will see it as a "new" changeset. All other repositories that had the old changeset will try to get the new one and ask that you merge it with itself.... This is not a good thing, so the short answer to your question is "don't do it".
If you could definitively purge that change from all other repos, so that only the local copy is left you could essentially get to the "draft" state. Note that if any repo has the "old" changeset, it will be pushed to the central repo someday and cause the mess that we are trying to avoid.
If the changeset is still local (e.g. in draft status), you can use hg commit --amend if it is the parent of the working directory.
If there are changes after it, I would use mq and hg qimport all the changes down to and including the one where you want to edit the commit message. hg qpop -a and then hg qpush to get to the patch that represents the changeset you want to edit. Then hg qrefresh -e and make your changes. Then just hg qfin -a and you should be good to go.
The advice from Edward is good — if you've pushed your changes to another repository, you should consider them set in stone and not update the commit message or any other aspect of them.
However, we're working on changing this in Mercurial. There is an experimental extension that will allow you to do more extensive history editing and push those edits to other repositories. It is called the Evolve Extension and it enables some behavior that is partly in the core of Mercurial and partly outside core.
When using evolve, you can edit the second-to-last commit message like this
$ hg update .^
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg commit --amend -m 'new commit message'
1 new unstable changesets
$ hg stabilize
more:[5] old tip changeset
atop:[6] new commit message
The extension allows you to do this as long as the changesets are in the draft phase. To keep them in the draft phase after pushing them somewhere, the repository you push to need to be configured as a non-publishing repository. You can read more about this in the Changeset Evolution Documentation.
I ran hg update -r REVISION to revert a branch to a previous revision, but when I try to push this to a remote repository it says "no changes found". How can I accomplish this?
To revert the files to a previous revision you can use
hg revert -r REVISION
This will change your working directory files to what they were at that revison. Then you
will need to commit these changes before pushing.
hg update -r REVISION changes the working directory's parent to be that revision as well as changes the contents of the working directory to that revision. This is not what you want here.
hg update only affects the state of your working directory, not the repository itself. If you want to "undo" the effects of one or more previous revisions, you will need to change the repository by committing a new changeset that reflects those changes. You could do it manually but hg's builtin backout command makes this easy to do. See a brief description here. There is a detailed explanation of backout here.
what would be an equivalent mercurial command (or workflow) for
git reset --mixed HEAD^
or
git reset --soft HEAD^
i.e. I want leave the working tree intact but get the repository back into the state it was before the last commit. Surprisingly I did not find anything useful on stackoverflow or with google.
Note that I cannot use
hg rollback
as I've done some history rewriting using HistEdit after the last commit.
Added to clarify:
After some rebasing and history editing I had ended up with A<--B<--C. Then I used HistEdit to squash B and C together, obtaining A<--C'. Now I want to split up the commit C' (I committed the wrong files in B). I figured the easiest way to do this was to get the repository back to state A (which technically never existed in the repository because of all the rebasing and history editing before hand) and the working tree to the state of C' and then doing two commits.
The right way to replicate git reset --soft HEAD^ (undo the current commit but keep changes in the working copy) is:
hg strip --keep -r .
-1 will only work if the commit you want to strip is the very last commit that entered the repository. . refers to the currently checked out commit, which is the closest equivalent Mercurial has to Git's HEAD.
Note that if . has descendants, those will get stripped away too. If you'd like to keep the commit around, then once you have the commit ID, you can instead:
hg update .^
hg revert --all -r <commit id>
This will update to the commit's parent and then replace the files in the working copy with the versions at that commit.
I believe the more modern and simpler way to do this now is hg uncommit. Note this leaves behind an empty commit which can be useful if you want to reuse the commit message later. If you don't, use hg uncommit --no-keep to not leave the empty commit.
hg uncommit [OPTION]... [FILE]...
uncommit part or all of a local changeset
This command undoes the effect of a local commit, returning the affected
files to their uncommitted state. This means that files modified or
deleted in the changeset will be left unchanged, and so will remain
modified in the working directory.
If no files are specified, the commit will be left empty, unless --no-keep
I have got a question regarding suprepositories. Our project is set up like this:
+ projectA
+ some files
+ dependencyA
+ some files
dependencyA is a subrepository. It was created this way:
cd projectA
mkdir dependencyA
cd dependencyA
hg init
hg pull ssh://hg#somerandomiphere/dependencyA
cd ..
echo dependencyA = ssh://hg#somerandomiphere/dependencyA > .hgsub
hg add
hg commit
hg push
If I make changes to the suprepository, then commit and push them from main project. Both of them will be pushed to the server since its recursive. Now my colleague wants to pull changes from the server. But since nothing was changed in the main project, it wont work. But if I change something in the main project and push it to server. Upon hg pull he will get the newest changeset and if he does hg update then, it will update the subrepository as well. This is expected behaviour.
Now my question would be, if there is a way to pull changes, but only for subrepository without making a new clone of it or what would be the best way to do it.
Subrepository in Mercurial wiki, p. 2.5 "Pull"
The 'pull' command is by default not recursive. This is because
Mercurial won't know which subrepos are required until an update to a
specific changeset is requested. The update will pull the requested
subrepositories and changesets on demand. To get pull and update in
one step, use 'pull --update'.
Note that this matches exactly how 'pull' works without
subrepositories, considering that subrepositories lives in the working
directory:
'hg pull' gives you the upstream changesets but doesn't affect your working directory.
'hg update' updates the contents of your working directory (both in the top repo and in all subrepos)
It might be a good idea to always pull with --update if you have any
subrepositories. That will generally ensure that updates not will miss
any changesets and that update thus not will cause any pulls. If the
pull with update fails due to crossing branches then 'hg update' must
be used to get all the subrepository updates.
What was suggested above works like I thought it would. The real problem was my way of creating a subrepository.
Instead of:
cd projectA
mkdir
dependencyA
cd dependencyA
hg init
hg pull ssh://hg#somerandomiphere/dependencyA
It should have been a simple:
hg clone ssh://hg#somerandomiphere/dependencyA dependencyA
As we know .hgsusbtate will lock the subrepo on specific revision after commit. This is what happened, but (!) doing hg pull in subrepository ended with an error
paths cannot contain dot file components
So this means my subrepo was locked on the revision it was updated after commit and it could not pull changes from its repository due to the error shown above. Why this happened is explained pretty well in this accepted answer.
Solution:
cloning is the way to go