Possible to branch in Perforce without creating a new folder? - branch

Is it possible to create branches in Perforce in a similar style to Git? I.e. without creating a new folder.
I would prefer for my client to manage the branches transparently whilst I work against a single copy of the directory tree on disk.
It seems awfully wasteful for the client to create an exact copy of the entire tree if you're only modifying say a couple of files. I much prefer Git's workflow in this regard.
If it's not possible using straight Perforce I'm happy to move to GitSwarm.
For info I'm running Perforce version 2015.1/1233444.

Possible yes, but with the centralized version of the system it involves a bit of 'magic'. Basically, the branch part doesn't need to involve the client at all anymore. Take a peek at p4 populate. That'll create another folder on the server, but won't do anything locally. Then you can edit your client workspace to map the branched files instead of the trunk files, and it'll just re-sync over top the files on your disk.
Now, having said that, if you wanted to take a look at our DVCS version of working, then you can just do "p4 switch -c " and it'll create a new branch locally, switch your workspace over to it (shelving any open current work in the process) and away you go.

My original answer was deleted because I thought a link was a better idea than repeating content. My mistake.
At any rate, I believe the DVCS features in Perforce Helix supply exactly the sort of thing you're after. In a blog I wrote in the subject (link here for reference) I explained how to create a new in-place branch with a single command:
p4 switch -c newBranchName
That will create a new branch with the name "newBranchName" and save any existing work in progress by default. To discover on which branch you're working you can use the switch command with the list argument as follows:
p4 switch -l
That would show you output like this, the asterisk showing that you're now working on the newBranchName branch.
newBranchName *
main
You can switch back and forth as you like, changing contexts as needed as often as you like. Your work in progress will continue to be saved on each branch in progress. When you're ready to merge your work back to main and push it back to the server, you can use the following sequence of commands:
p4 switch main
p4 merge --from newBranchName
p4 resolve –as
The first command switches back to the main branch, the second merges your work from the newly created branch into main, and the third resolves any potential conflicts automatically. If there are any conflicts that can't automatically be merged, then you can use the usual commands to walk through the resolution process.
Alternately, if you prefer to stick with Git, you can use that directly with our Helix Versioning Engine through our Git Fusion technology or use Git directly with our new GitSwarm technology. That is a pretty amazing option (in my opinion) as it makes it possible to mirror content automatically and bidirectionally between GitSwarm and the back end server. That way you get all the features of Git with GitSwarm (which itself is based on GitLab) and all the goodies from the rest of Helix.
Hope that helps!

If you use streams (Perforce's "managed" version of a branch, as opposed to doing completely ad hoc inter-file branching with arbitrary paths), it's pretty simple. As P4Gabe said, "switch -c" is a one-shot option on a local server.
On a shared server it's only a little more complicated because you have to do the "populate" explicitly (this is to keep naive users from accidentally branching lots of files lots of times on a shared server), but it's still only a few steps and it's something that you as an advanced user could script easily:
p4 stream -P (current stream) -t development (new stream name)
p4 populate -r -S (new stream name)
p4 switch (new stream name)
The equivalent is possible using ad hoc ("classic") branches as well if you have a good understanding of how client views work -- use populate to create the new branch, modify your client view to map the new branch into the namespace currently occupied by the old branch, and sync.
This blog post on what exactly "p4 switch" does might help if you're trying to engineer your own solution that's similar-to-but-not-quite the "switch" command: https://www.perforce.com/blog/150428/p4-switch-switching-it

Related

Consolidate Perforce `add` and `edit` file operations

To automate Perforce staging, I face a dilemma that add and edit are two different ops and they work on files of different SCM status, i.e., "already under SCM or not".
This is different from git where staging is uniformly add.
I'd like to have something like pseudo-code:
filepath = '/path/to/myfile.ext'
if p4.is_under_scm(filepath):
p4.edit(filepath)
else:
p4.add(filepath)
or better yet, simply hide the detail with:
p4.staging(filepath)
How should I achieve this with calling p4 command-line program?. I'm not using any programming-language bindings right now.
You might want to use the p4 reconcile command, which automatically opens workspace files for an action that matches their current state relative to the depot.
Keep in mind if you go this route that reconcile operates only on unopened files that are different from the depot version, so it's meant to be used after making local modifications (this is different from the standard workflow where you open a file with p4 edit prior to editing it -- the idea is that you use reconcile to fix things after the fact if you've had to work disconnected or something like that). In addition, if you change your mind about what you're doing with the file (e.g. you delete the local copy after it's been opened for edit but before you submit), you may need to revert -k it and re-reconcile to ensure that it's open for the correct action.
For something that matches the pseudocode in your question, you probably want the p4 have command, which tells you if a local file corresponds to a depot revision (and if so which one). p4 edit only works on a file that you have, whereas p4 add would be for a file in your workspace that does not correspond to an existing depot file. (A very subtle point here -- it's possible for the file to map to a depot file despite not having been synced from the depot! If that's the case you'll hit a conflict when you go to submit your add.)

What is the correct way to create branch in RCS, and do you need to set a lock first?

I am looking for best practices using branches in RCS.
I had read the man page for rcs and ci and also browsed at the following links:
http://www.gnu.org/software/rcs/manual/html_node/Concepts.html
http://www.gnu.org/software/rcs/manual/html_node/Quick-tour.html
Suppose i have revision 1.3 on tip of the trunk.
I now want to change file 1.2 (as 1.3 have several other changes I cannot yet use).
I understand I can create branch on revision 1.2 using ci -r1.2.1
My question are the follows:
1. Do I need to set a lock on the file? If so, on which revision?
2. If no lock set, I cannot use -u flag in order to keep the file in my local dir. In case I wish to do so, is it still possible without co the file again?
Side note: I feel RCS does not suit my company needs however migrating to another system is not my decision to make, so currently I need to keep working with it.
I'm looking for much the same thing, but seeing you've had no answers, I'll offer my current practice:
I use branches for development, not for keeping different variants going in parallel. The trunk is reserved for my best, presumably working, code on the and I try not to check in anything there that might break it. I branch the code when I want to start a line of development that will take some time, break it for a while, is an experiment I might have to be abandon, etc.
To start a new line of development I change the default branch to a new branch off the trunk rev that's to be the base of my code, and force a checkin onto that branch, with:
rcs -b1.2.1 foo.cpp
ci -f1.2.1 -l foo.cpp
Now I can dive in to developing the branch, and my next check-ins will go onto the new branch instead of onto the trunk. Whether you lock a revision or not is only relevant to whether you intend to modify the working file.
You're correct that you can't keep both revisions, trunk-tip and branch-tip in the same folder; they have the same file name. But you can check out one of them with a -p switch which forces the output to stdout (instead of to a local file) which you can then redirect into a sub-folder, or to a local file with a unique name.

Exchanging work before accurev promote

My colleague and I are participating in a huge project located in Accurev. We've already created own workspaces backed with some stream (let's call it zzz-stream) which is used by many other participants, not only by us.
The point is that we want to exchange our work between our workspaces, make some changes, exchange again, etc. BEFORE making the changes accessible for others, i.e. in other words we don't want to propagate our changes until it is stable and tested, but we want be able to work on it together.
My idea was to create new stream (yyy-stream) backed with zzz-stream, and then change our workspaces to be backed with yyy-stream. But unfortunately I have no rights to create streams.
My second idea was to use a workspace as backed stream, but it doesn't work because Accurev can't use ws as backed stream.
Is there any solution for our problem?
UPD: I accepted Brad's answer as most detailed. However Accurev is too heavy and sluggish to be used effectively. So actually I prefer to use Git for internal needs over the accurev workspace. (see Accurev externally, git internally)
Your idea of creating the yyy-stream is the EXACT right way to do it. The other options are decent workarounds for one-off situations, but creating the extra stream is simple and is fully leveraging AccuRev's capabilities.
That being said, I understand that your admins have stream creation locked down. They of course want control, but should be allowing for maximizing developer productivity and not forcing workarounds like this. My guess is they have stream creation locked down to a particular group being enforced by the server-admin trigger. One common thing I have seen other large sites do is:
- allow streams to be freely created off of a list of acceptable streams (easy to do in the trigger)
- enforce naming rules on the stream creation. This is important to admins in large sites to keep things organized. Again, this is very easy to enforce via the server-admin trigger.
Bottom line, if this is a common situation, work with the admins to allow this capability as per the above. If they have any questions, they are more than welcome to contact AccuRev and we will help them out.
Your idea on using another stream for you and your peer is a good one and is commonly called a collaboration stream. If your site has stream creation locked down, you would need to work with your AccuRev administrator to make that happen.
Another option is for you and the other developer to pull the keeps from the other workspace into your own stream. This relies on both of you being diligent about doing keeps and then you can look at the history of the other developer's workspace to find the keep operation, right-click that transaction and then select Send to Workspace. The destination workspace must be your own.
A third option (more for a situation where you are in your workspace and know exactly what file you want to grab the other users changes)is to bring up the version browser for the file, right click and select history/browse versions. Look for the other workspace, highlight the version in that workspace, right click and select send to workspace. This will checkout that version into your workspace.
This is similar to the change palette suggestion but quicker if your looking to this on a file basis.
Another idea is to use different version control system (e.g. git or svn) over Accurev workspace to exchange the changes and keep our history separated from zzz-stream. (similar to Accurev externally, git internally) Only changed files should be added to other VCS, not whole project. Some merge problems occur though.

bazaar pull special usage

I have local folder that is branch from formal_versions.
My workflow is:
Mkae changes and than commit them
The integrator merge them in his local branch.
The integrator push its local branch to formal_versions
I use pull to make my local branch identical to formal_versions
This is working fine.
However what should I do in the following scenario:
After pull from formal_versions , I compile the code. As a result , some workspace and obj file are changed (I.E date and time of compilation) and of cource , bazaar explorer inform me on modified files
I again want to make my branch mirror of formal version. What should I do?
A. Why using pull again says that "nothing to pull" even if
I use --overwrite switch ? it is suppose to make my local branch as mirror of the pulled branch...
B. Is my only option is to use revert working tree?
It is generally considered best practice (as well as good for one's sanity) not to version files that are the result of the build process. Executables, shared libraries, and even source files generated from by a 4GL are examples. You can ignore files by using bzr ignore <pattern>, for example bzr ignore *.exe. If the files are already versioned, you will also have to remove them using bzr remove.
bzr pull says there is nothing to pull because the formal version has had no new commits since your last pull.
If you must version the files in question, bzr revert is the only way I know of when bzr pull does not find new revisions. If there had been new revisions in the formal branch, the files should be updated (and will potentially be reported as conflicts).

Task per branch with perforce

i'm preparing a seminary about p4 and i'm trying to find the best way to use the "Task per branch" methodology, now i'm using the following steps: (all by CLI)
Set my client to the root depot in order to create the new branches.
View:
//depot/... //myMachine/...
p4 -c myClient integ -v //depot/MAIN/... //depot/myBranchX/...
p4 -c myClient submit -d "Branching"
Change again my client aiming to the new branch.
View:
//depot/myBranchX/... //myMachine/...
p4 -c myClient sync
i'm wondering if there's a fastest/better way to do it. Specially working with huge repositories and branches.
Thanks!
M.
So... you want to create a branch for each task/bug and you want the newly created branch to mapped to client/workspace as if it was the trunk. And you want to be able to this via the command line or by running a scrip. Correct?
OK.
What is there a reason you want to adopt this workflow? Are you working on critical software, i.e., life/death scenario where every task is isolated and needs to be thoroughly vetted before integrating into the main line.
Unless you have a situation like above I would recommend against this workflow. Creating a branch for every task, especially in a large repository will eventually bring your Perforce server to a crawl. An similar situation was posted recently on the Perforce Blog as an Anti-Pattern (what not to do). Perforce Anti-Patterns Part 2: Overuse of branching.
Think about it.
If you still want to proceed, then you can achieve what you want by writing a shell script (DOS, Bash, Python**) that groups the above commands together taking a few arguments for the task/branch name etc. Comment if you need further help in doing this.
** preferred, then compile the script using py2exe as an executable for distribution.