Bug reporting

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Welcome, testers! Bug reporting and feature requests are managed with Freedesktop's Phabricator. You need a phabricator account to file tasks and comment on them. Take a look at the existing list of bugs/feature requests to see if your problem has already been reported (hint: use control+F in your browser to search!).

  • To report a bug/problem in the software, create a task and set Projects: Pitivi.
  • To request a new feature/enhancement, create a task, set Projects: Pitivi and Priority: Enhancement.


Example queries

  • Everything - All the tasks (bug reports and feature requests).
  • Patches — All the patches (diffs) attached to tasks that have not yet been merged.
  • Pitivi tasks for newcomers — feature requests and some small bugs that are considered easier for new contributors to tackle.

Providing debugging information

Sharing sample files, projects, and "scenarios"

In some cases we might ask you to share sample media files with us to debug a particular issue. If you don't have your own hosting space, we have a FTP account with unlimited space available for this purpose, provided by idmark.ca.

  1. Using a FTP client (such as FileZilla, available on most Linux distributions), connect to "idmark.ca" using the username "pitivisamples@idmark.ca" (@idmark.ca is part of the username). Ask us for the password on IRC.
  2. Please follow our simple naming convention and put your files in a folder called with the ID of the bug report (eg. T3553) so we can find it easily.
  3. Your uploaded files will be in a private staging folder (only visible through FTP); once reviewed, we may move your uploaded files to http://pitivi.ecchi.ca/user-contributed-samples/ for ease of access.

You can also share in a similar way a project archive containing the project and all the media is uses:

  1. Use the “Select unused clips” feature to easily remove unused media from your project, this will help you save space (and upload time).
  2. Click the menu button top-right and choose the “Export project as tarball...” menu item. Save the .xges_tar file somewhere. It will contain your project file and its associated media.
  3. Upload it as described above.

In addition to the project archive, it is extremely helpful to provide "scenario" files. These are automatically generated each time you use a project and contain the operations you made. Combined with the project archive, these allow us to perform exactly the actions that have occurred to trigger the bug. This makes reproducing the issue on our machines a very easy and reliable process, which saves you a ton of time! Here's how to provide scenario files to facilitate the process:

  1. Save your project, right before triggering the bug.
  2. Trigger the bug (make Pitivi crash or freeze).
  3. Get the last/newest scenario file from ~/.cache/pitivi/scenarios/ or ~/.var/app/org.pitivi.Pitivi/cache/pitivi/scenarios/
  4. Upload it as described above, so we can reproduce your issue and integrate it into our test suite so that it does not happen again in the future!

Stack traces for crashes

When reporting a crash or when the application freezed deadlock, it would be good to provide a stack trace.

When running with Flatpak

Make sure you have the GNOME Sdk and Debug symbols installed:

 GNOME_REPO=$(flatpak remote-list --user -d | grep "http://sdk.gnome.org/repo/" | awk '{ print $1 }')
 flatpak install --user $GNOME_REPO org.gnome.Sdk 3.20
 flatpak install --user $GNOME_REPO org.gnome.Sdk.Debug 3.20
 flatpak install --user $GNOME_REPO org.gnome.Sdk 3.22
 flatpak install --user $GNOME_REPO org.gnome.Sdk.Debug 3.22

Start a shell in the Pitivi bundle environment

 flatpak run -d --command=bash org.pitivi.Pitivi

Start Pitivi inside gdb

 gdb python3 -ex "run /app/bin/pitivi"

When Pitivi crashes, run bt full to get the backtrace. When Pitivi freezes, press Ctrl+Z and run thread apply all bt to get the backtraces for all the threads.

When running from the packages of your Linux distro

See GNOME's Getting Traces instructions for some comprehensive documentation and tips on the subject.

For those of you who already know how to install the relevant debug packages etc, we provide you with some simple reminders below of commands that can be particularly useful in Pitivi's context.

When you want to "attach" to an existing Python process (useful for deadlocks, where the application will be hung instead of crashed):

gdb python3 THE_PITIVI_PROCESS_NUMBER

When you want to run Pitivi entirely in gdb from the start:

gdb python3
set pagination 0  # avoids the need to press Enter to "scroll"

run /usr/bin/pitivi  # the version installed system-wide.

When Pitivi crashes, run bt full to get the backtrace. When Pitivi freezes, press Ctrl+Z and run thread apply all bt to get the backtraces for all the threads.

Debug logs

When you need to know what’s going on inside pitivi, you can launch it with a debug level. In loggable.py, there are five levels: ( ERROR, WARN, FIXME, INFO, DEBUG, LOG ) = range(1, 7). As such, if you want to see errors and warnings only, you launch

PITIVI_DEBUG=2 bin/pitivi

...and if you want to see everything you do

PITIVI_DEBUG=6 bin/pitivi

If that's "too much" and you want to focus on particular parts of the code, you can do so. For example, you can get output from the Timeline and MediaLibraryWidget classes only:

PITIVI_DEBUG=timeline:6,medialibrarywidget:6 bin/pitivi


Here are various examples of commands you can use to generate detailed debug logs that include not only Pitivi's debug output, but also GStreamer's:

A basic log can be obtained by running:

PITIVI_DEBUG=*:5 GST_DEBUG=2 bin/pitivi > debug.log 2>&1


To get debugging information from Non-Linear Engine, you could use:

PITIVI_DEBUG=5 GST_DEBUG=3,nle*:5,python:5 bin/pitivi > debug.log 2>&1

The information most likely to be useful would probably be the debug info from GES in addition to Pitivi's:

PITIVI_DEBUG=5 GST_DEBUG=ges:5 bin/pitivi > debug.log 2>&1;

Some additional tips:

  • When using GST_DEBUG, the resulting logs will most likely be too big to be attached to a bug report directly. Instead, compress them (in gzip, bzip2 or lzma format) before attaching them to a bug report.

Python performance profiling

In the rare cases where a performance problem is caused by our UI code, you can profile Pitivi itself, with this command (and yes, "JUMP_THROUGH_HOOPS" is needed for this case, it is an environment variable of bin/pitivi:

JUMP_THROUGH_HOOPS=1 python3 -m cProfile -s time -o pitivi_performance.profile bin/pitivi

The resulting "pitivi_performance.profile" file can then be processed to create a visual representation of where the most time was spent and which functions were called the most often in the code. See also Jeff's blog posts on profiling.