Make simple revision merges and branch switching much easier


Keywords
svn, subversion, wrapper
License
GPL-2.0+
Install
pip install eazysvn==1.14.0

Documentation

eazysvn

https://github.com/mgedmin/eazysvn/workflows/build/badge.svg?branch=master

Eazysvn is a Python script that simplifies some common operations with Subversion branches.

Installation

Get it from the Python Package Index:

pip install eazysvn

You'll need Python 2.7 or later, as well as the Subversion command-line client.

Usage

Getting help

At the shell prompt type

eazysvn help

It will print a list of commands. Some of the commands have aliases:

ezswitch = eazysvn switch
ezmerge = eazysvn merge
ezrevert = eazysvn revert
ezbranch = eazysvn branchurl

Switching between branches

In a subversion working directory run

ezswitch -l

to see all the branches available in your project. This assumes your Subversion repository uses the standard layout with 'trunk', 'tags', and 'branches' in it.

Then run

ezswitch branchname

to switch to a branch, and

ezswitch trunk

to switch back to trunk.

Working with branches

Say you're working on a project and in the middle of a difficult refactoring suddenly realize the changes you've made are too risky for trunk you want to put them in a branch. Run

ezswitch --create my-branch

This will create a new branch and switch your working directory to it. All your changes in progress are kept intact and you can commit them directly to the new branch with svn commit.

Seeing all the changes on a branch

You may want to see the overall diff of changes made on a branch since it was created, say, to review it before attempting a merge.

eazysvn branchdiff branchname

does exactly that. For extra readability, install colordiff and use

eazysvn branchdiff branchname | colordiff | less -R

Merging branches

After you've finished hacking on your branch, you will want to switch back to trunk and start merging. Run

ezswitch trunk

then

ezmerge my-branch

You will see the svn command used for the merge as well as a log of all the changes. Fix merge conflicts (if any), run the test suite, then commit. The output of ezmerge helps you produce an informative commit message.

If instead of merging the changes to your working directory you'd like to see the combined diff, pass the -d (or --diff) option to ezmerge

ezmerge -d featurebranch

Cherrypicking

If you want to merge only some of the changes made in a branch, you can pass the revision number (or a range) to ezmerge. For example, to backport a bug fix implemented in revision 1234 of trunk to a release branch,

ezswitch release-branch
ezmerge 1234 trunk

You can also merge a range of revisions

ezmerge 1234-1236 trunk

This range is inclusive, unlike Subversion. If you want to, you can also use Subversion-style half-open ranges as well

ezmerge 1233:1236 trunk

The --diff option works here too.

ezmerge -d 1234-1236 trunk

Reverting committed changes

It's like cherry-picking, but in reverse: you want to unapply changes already committed to this branch.

ezrevert 1234

Making tags

To tag the current version of the source tree in your working directory, run

eazysvn tag tagname

Manipulating branches

To remove a branch completely, run

eazysvn rmbranch branchname

To rename a branch, run

eazysvn mvbranch oldbranchname newbranchname

To do other kinds of operations, eazysvn provides a shortcut that lets you use branch names instead of full branch URLs (this bit assumes a Unix-like shell):

svn ls $(ezbranch branchname)
svn diff `ezbranch branch1` `ezbranch branch2`

Another possibly useful eazysvn command is branchpoint. It shows the revision when a branch was created. For example, to see the changes in trunk that are not present in a branch, run

svn diff -r `eazysvn branchpoint branch`:HEAD `ezbranch trunk`

Overall options

All commands that require a branch name as an argument accept a -l (or --list) option that lists all branches, e.g.

ezbranch -l

All commands that make changes to the repository or working directory accept a -n (or --dry-run) option that just prints the svn commands that would otherwise be executed.

ezmerge -n 1234 otherbranch

All commands that make changes to the repository (create/remove/rename branches or tags) accept a -m option with a commit message. If not specified, you'll get a text editor spawned by subversion itself to type the commit message.

ezswitch -c newbranch -m "Create branch for the new feature"

Many of the commands accept other options as well. Use

eazysvn cmd --help
ezmerge --help
ezswitch --help
etc.

to discover those.

Appendixes

Revision numbers

A revision to Subversion means the state of the whole project tree at a given instant of time. Sometimes the changeset that converts one revision to another is more interesting. When you specify a single number N to ezmerge, it assumes that you want to merge the changeset that changes revision (N-1) to revision N.

If you specify a range N-M, ezmerge.py merges all the changesets that change revision (N-1) to revision M. For compatibility with svn merge you can specify the revision range as N:M, and ezmerge will merge all the changesets that convert revision N to revision M. In the last case N can be greater than M, which is useful if you want to revert some changes, although ezrevert is more convenient for that.

When you specify ranges (N-M or N:M) M can be a special name HEAD. It means the latest revision in the repository.

You can also specify a special range ALL, which means all the changesets made in the branch. ezmerge will parse the output of svn log to get the revision numbers for you. ezmerge branchname is a shortcut for ezmerge ALL branchname.

For easier copying & pasting from svn log output, you can prefix numbers with the letter r, e.g. r1234.

Branch names

Eazysvn expects you to use the traditional repository layout, and can find its way from any of these to any other of these URLs if you specify the desired branch name as 'trunk', 'foo', or 'bar'.

scheme://server/path/to/svn/repo/trunk/subdirs
scheme://server/path/to/svn/repo/branches/foo/subdirs
scheme://server/path/to/svn/repo/branches/bar/subdirs

You do not have to be at the top of the project to switch or merge, any subdirectory will work. The part of your checkout above the current directory will not be touched by the merge/switch.

An alternative scheme is partially supported:

scheme://server/path/to/svn/repo/trunk/subdirs
scheme://server/path/to/svn/repo/branch/foo/subdirs
scheme://server/path/to/svn/repo/branch/bar/subdirs

Eazysvn will be able to find the location of trunk or other branches if you start out in a branch checkout, but it won't be able to find your branches from a trunk checkout. This is a bug that should be fixed one day.

You can force eazysvn to use any nonstandard scheme if you explicitly enter the prefix with a slash in front of the branch name, e.g. ezswitch feature/foo in a trunk checkout would switch from

scheme://server/path/to/svn/repo/trunk/subdirs

to

scheme://server/path/to/svn/repo/feature/foo/subdirs

If you start out in a checkout of such a nonstandard location, Eazysvn won't be able to find the location of trunk or other branches. This is a bug that should be fixed one day.

Branch merge logic

When you merge a branch (to trunk or to another branch), eazysvn uses svn log to find the revision number when the branch was created. Then it merges all the changes ever committed on that branch.

This means you usually can't merge from the same branch more than once. It's a consequence of Subversion's lack of merge tracking.

Also, since there's no fancy searching for common ancestors or anything like that, if you branch A from trunk make some changes, then branch B from branch A, make some changes, then if you ezmerge B on trunk, you won't get any changes made in branch A.

When you merge a trunk to a branch, eazysvn again uses svn log to find the branch point and then merges all the changes made on trunk since that revision.

It's a bad idea to merge from trunk to a branch, because then you won't easily be able to merge that branch back to trunk. You may try, subversion might apply the already-applied changes twice cleanly, but it's a matter of luck.

Keep it simple: always merge a branch only once, back to the same place you branched from, and you'll avoid trouble. Remove branches you've merged to avoid accidentally making new changes that will be harder to merge.

Changelog

See CHANGES.rst

Licensing and source code

Eazysvn is licensed under the GNU General Public Licence version 2 or 3.

You can get the latest source code with

git clone https://github.com/mgedmin/eazysvn

Eazysvn began life as Philipp von Weitershausen's ezmerge.py. Then Marius Gedminas took over, created a home page, and started adding random features.

Bugs

Report bugs at https://github.com/mgedmin/eazysvn/issues

Wishlist/To do

ezmerge should accept a comma-separated list of revisions (1,2,4-6,9).

There should be eazysvn rmtag and eazysvn mvtag.

eazysvn help cmd should be the same as eazysvn cmd --help and not an error.

eazysvn -n cmd should be the same as eazysvn cmd -n and not an error.

eazysvn should do an svn ls to discover the branching scheme in use ('branch' or the more traditional 'branches').