trusty (3) Padre::Manual::Hacking.3pm.gz
NAME
Padre::Manual::Hacking - Guide to hacking on Padre
DESCRIPTION
This is the Padre Developers Guide.
It is intended for people interested in hacking on Padre, and specifically hacking the core distribution.
Getting Started
This document assumes that you are working from a copy of Padre checked out from the official repository.
Rather than just checking out the Padre distribution alone, we recommend that you checkout the entire
repository trunk, which will provide you with Padre itself, miscellaneous tool scripts, and most of the
plugin distributions as well.
The specific path you want to check out is...
http://svn.perlide.org/padre/trunk
Extra Files
The trunk contains primarily a set of directories, one for each CPAN distribution created for Padre by
the development team.
In addition, there are some additional scripts that are for development purposes and are not part of the
releases themselves.
Padre/dev
This is a launch script used to start Padre in developer mode. This mainly automates a couple of
conveniences, such as using a local .padre directory instead of your system one, and including lib in the
@INC path to prevent needing to run make constantly.
tools/release.pl
Used to release Padre.
tools/update_version_number.pl
Similar to the ppi_version tool from CPAN, this updates the version number.
Bug Tracking
Padre uses Trac for bug tracking.
The main web site of Padre is actually its Trac <http://padre.perlide.org/>
Patching
Check out the trunk (<http://svn.perlide.org/padre/trunk/>) and use svn diff to create your patch while
your current working directory is the trunk directory.
Please send patches either to the padre-dev mailing list or add them to trac to the appropriate ticket.
Branching
Usually we use the trunk for all the development work so we can see issues and fix them quickly. At least
some of us already use Padre for the development work running it from the workspace so if someone breaks
trunk that will immediately affect some of the developers.
So please don't intentionally break the trunk!
If you think your change is relatively large and you feel more comfortable working on a branch, do it.
Change Management
We try to work with small changes. There are no exact rules what is small and what is already too big but
we try not to mix unrelated issues in one change. If you need a styling change or white space change, do
it it in a separate commit.
Commit messages are important. If a commit relates to a ticket please try to remember adding the ticket
number with a # sign ( #23 ). The GUI of Trac will turn it into a link to the relevant ticket making it
easier to find related information.
Most of the current major committers monitor the commit messages to see what everyone else is doing, so
please write them as if they are going to actually be read within a few hours of you making the commit.
Tickets/Issues/Bugs
We are using Trac as the issue and bug tracker.
When adding a note that relates to one of the commit in SVN please use the r780 format. That allows Trac
to create links to the diff of that revision.
Code review
We don't have formal code-review but in response to the commit messages we sometimes reply with comments
to the padre-dev mailing list.
You are also encouraged to do so!
STYLE
We're not overly strict about code style in Padre (yet), but please don't feel offended if somebody
corrects your coding style.
There are a number of relatively simple preferences that are more or less enforced, but none of this is
automated. We prefer humans over automation for this because PerlTidy has something of a history of doing
things overly strictly, which can sometimes destroy clarity for the sake of correctness.
In general, the code style preferences for Padre are guided by ease of understanding code, and thus ease
of maintenance.
Tabs instead of Spaces
Use one tab character for each indentation level at the beginning of a line.
There are a lot of people working on Padre, with indent preferences ranging from two to eight spaces.
Using tabs allows all of the development team to work with code at the indent level that is most
comfortable for their eyes.
In particular, allowing the use of large (eight or higher) tabs enables developers with visual processing
or eye-sight issues (astygmatisms, mild short-sightedness, figure-ground problems) to effectively
contribute to Padre.
If your editor doesn't support tabs properly, well that's clearly a temporary probably because you will
eventually be switching to Padre, which DOES support tabs properly.
Additionally, there current plan for project support does include correctly supporting project specific
tab-versus-space settings, so you can use spaces for your code, and Padre will just switch and Do The
Right Thing when you work on the Padre project.
After the initial indentation, do not use tabs for indentation any more. Instead, use the appropriate
amount of spaces to make things line up.
Example: (Where you put the opening brace isn't
important for this example!)
sub baz {
if (foo()
and bar())
{
# ...
}
}
Method and Subroutine Naming
Methods in Padre itself must be lowercase, and should generally consist of complete words separated by
underscores. (e.g. Use ->check_message instead of ->chkMsg).
Methods in all capitals are reserved for Perl-specific methods such as "DESTROY"
Methods in StudlyCaps are reserved for the Wx bindings.
Separating This allows us to be clear which methods (or overrided methods) are part of the Wx layer, and
which are part of Padre itself.
Accessors
If a value is set once during the constructor and then not changed afterward, use a accessor name which
matches the original parameter.
my $object = Class->new(
value => 'something',
);
sub value {
$_[0]->{value};
}
Accessors which can change post-constructor should be named "get_foo" and "set_foo". Do not use mutators.
For simple accessors, we encourage the use of Class::XSAccessor for accessor generation. This not only
makes them significantly faster, but also makes debugging easier, because the debugger won't descend into
every single accessor sub.
HEAVY-DUTY DEBUGGING
Don't bother reading this sectionif you don't know any C or if you just want to get started hacking
Padre!
If you're planning to do a serious debugging session, you may want to set up Padre with a debugging perl
and debugging version of Wx. Particularly the core developers are encouraged to have a go at this
because the debugging version of wxWidgets will show various warnings of failed assertions which may
otherwise go undetected. This is a bit of work to set up and not very useful for a casual hacker as this
will involve compiling your own perl, wxWidgets, and Wx.
Here's a rough how-to for Linux and similar OSs:
Building your own debugging perl
• Get the perl sources from http://cpan.org/src/README.html or via git. As of this writing, perl 5.12.1
is the latest stable release.
• Extract the sources and run
./Configure -Dprefix='/path/for/your/perl' -DDEBUGGING -Dusethreads -Duse64bitall -Dusedevel -DDEBUG_LEAKING_SCALARS -DPERL_USE_SAFE_PUTENV
Remove the "-Duse64bitall" if you have a 32bit OS (or machine). Keep answering the questions with
default (hit Enter) except for the question about additional cc flags. Here, put the default settings
that are suggested in the [...] brackets and add two options:
-DDEBUG_LEAKING_SCALARS -DPERL_USE_SAFE_PUTENV
Afterwards, keep hitting return until the configuration is done.
• Compile "perl" by typing "make" or for multiple CPUs, type "make -jX" where X is the number of CPUs+1.
• If all went well, type "make install" to install your own private debugging perl.
• Check whether the executables in /path/to/your/perl/bin all contain the version numbers of perl. You
may want to create symlinks of the basename. If so, cd to the directory and run:
perl -e 'for(@ARGV){$n=$_;s/5\.\d+\.\d+//; system("ln -s $n $_")}' *5.*
Check that there's now also a perl symlink to perl5.12.1 (or whatever version of perl you built).
• Setup the environment of your shell to use the new perl. For bash-like shells, do this:
export PATH=/path/to/your/perl/bin:$PATH
csh like shells probably use something like "setenv" or so.
• Try running "perl -V" to see whether your new perl is being run. (See also: "which perl")
Make sure "perl -V" shows these particular "compile-time options":
DEBUGGING DEBUG_LEAKING_SCALARS PERL_USE_SAFE_PUTENV
PERL_USE_DEVEL
There'll certainly be others, too.
Building your own debugging wxWidgets
• Make sure your ~/.cpan is owned by you and not being used by another perl. Maybe clean up
~/.cpan/build/* so there's no collisions.
• Run cpan. (NOT as root!)
• If you like, install "Bundle::CPAN" for convenience. Potentially restart cpan afterwards. Check whether
the modules were installed into your fresh perl at /path/to/your/perl/lib.....
• From cpan, type "look Alien::wxWidgets". You should get a new shell in an extracted "Alien::wxWidgets"
distribution.
• Build wxWidgets by running:
perl Build.PL --debug --unicode
Hopefully, it won't say you're missing any dependencies. If you're missing any, quit the shell and
install them from the cpan shell before continuing.
"Build.PL" will ask you whether you want to build from sources. Yes, you do. Have it fetch the sources
as .tar.gz.
./Build
./Build test
./Build install
Installing a debugging Wx.pm
• Now, you want to set up your own Wx.pm with debugging enabled. First, install the prerequisites for
Wx. I did it like this:
cpan> look Wx
...
$ perl Makefile.PL
... blah blah missing this or that ...
Take note of the missing dependencies, exit to the CPAN shell, install the missing modules, then "look
Wx" again.
• If you have all Wx.pm dependencies in place, build "Wx" like this:
perl Makefile.PL --wx-debug --wx-unicode
make
make test
make install
Installing Padre from SVN
• Once Wx.pm is installed, check out Padre from the Subversion repository and cd to its directory under
trunk/Padre.
• Run "cpan ." to automatically install all dependencies of Padre!
• Run the following to set up Padre:
perl Makefile.PL
make
• Run dev to start Padre from your checkout.
perl dev
or with all plugins loaded:
perl dev -h
or with the Perl debugger:
perl dev -d
• Don't be annoyed by the Wx popups complaining about assertion-failures. They indicate potential bugs
that probably need attention. If you get these, that means it was worth the effort to build a debugging
perl and Wx! Note that the stack backtraces given are at the C level, not Perl backtraces.
SUPPORT
For support with Padre itself, see the support section in the top level Padre class.
For support on hacking Padre, the best place to go is the #padre channel on <irc://irc.perl.org/>.
COPYRIGHT
Copyright 2008-2010 The Padre Team.