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Convert Firefox into Emacs

~ parkouss ~ Leave a comment

Firefox is a great browser. One of the reasons I really love it is because it is highly configurable: as an Emacs user, I wanted to use emacs key bindings inside Firefox – well, it’s easy to do that. And much more!

Most of the magic for me comes from the awesome keysnail addon. It basically convert Firefox into Emacs, is also highly configurable and have plugins.

For example, I now use C-x <left> and C-x <right> to switch tabs; C-x b to choose a specific tab (using the Tanything plugin) or C-x k to kill a tab. Tabs are now like Emacs buffers! Keysnail support the mark, incremental search (C-s and C-r), specific functions, … Even M-x is implemented, to search and run specific commands!

Also I use the Find As You Type Firefox feature, for links. It’s awesome: I just hit ‘, then start typing some letters in a link title that I want to follow – I can then use C-s or C-r to find next/previous matching links if needed, then I just press Return to follow the link.

I can browse the web more efficiently, I am less using the mouse and I can reuse the same key bindings in Emacs and Firefox! I keep my configuration files on github, feel free to look at it if you’re interested!

Happy browsing!

Python [aggressive] pep8 conversion using autopep8

~ parkouss ~ 1 Comment

Some time ago, I started to look at Talos, the python performance testing framework for firefox that is usable on Windows, Mac and Linux.

Talos has been around for a long time, and has seen many contributors! Unfortunately the codebase reflects that, and as an example there was simply no common code style around for all the Python files.

Sometimes a 2 spaces based indentation, sometimes 4 spaces based, sometimes something else. No limit for the lines length. This end up with something that is really hard to read, understand and maintain. So one of my first goal was to try to clean this up.

And I heard about autopep8. As the name suggests, this is a tool (command line) that will automatically do some pep8 conversion on Python source files.

Awesome! I highly recommend that to you if you are trying to adapt the coding style of some Python code to pep8 convention, this worked really well for me. This is a pain to do that by hand, and almost impracticable when the indentation needs to be fixed, but autopep8 makes that for you in a safe way.

Tip: the –aggressive flag is really nice for fixing long lines.

So, as an example this is how I used autopep8 on talos:

autopep8 --recursive --in-place --aggressive --aggressive /path/to/talos

Simple and effective. See the usage documentation to see with an example what it really does and other command line flags.

RunSnakeRun – graphical visualisation of dumped python profiling data

~ parkouss ~ Leave a comment

If you are a Python developer like me, you probably know the profile and cProfile modules that provides deterministic profiling of Python programs.

These modules are awesome – however, when it comes to analysing the data to improve your program, the provided pstats module is generally not powerful enough if you have quite a large codebase.

And here graphical tools comes in handy! I tried RunSnakeRun, and this is a really great program that allows you to analyse the profiling data under multiple angles (a nice view is by file), so you can find easily the bottlenecks and fix them.

RunSnakeRun helped me to improve the “mach help” command. It is a cross platform tool. Note that if you are on GNU/Linux and that you have the KDE desktop (or don’t mind to install the required KDE dependencies), KCacheGrind can be used with Python also.

rcontrol – a new python 2 and 3 ssh high level library

~ parkouss ~ Leave a comment

I just started to build a new python library to ease access and control of remote hosts via ssh: rcontrol. It is based on paramiko and offer a high level API to execute remote and local commands in parallel.

rcontrol is an alternative to fabric – but rcontrol is not built with the specific deployment use case in mind, do not use global variables (I really don’t like the fabric global env), is intended to be more user-friendly for tasks synchronisation (doing things in parallel) and finally is compatible with python 3.

This is actually not a Mozilla contribution. Still some part of the library share a piece of code with MozBase, because I reused the same code I wrote in one of the patches, to separate lines of output streams from a process (see bug 794984).

If rcontrol sounds like what you need, give it a try. 🙂 Look at the README for a detailed description and more information about this tool – then at the documentation. If you find a bug or want a new cool feature please report it, or even better create a github pull request (contributions are more than welcome!). And if you like it, star it on github!

Python code cleanup – vulture

~ parkouss ~ Leave a comment

I’m pretty sure you all already know about flake8, a great tool that combine other tools (PyFlakes, pep8 and Ned Batchelder’s McCabe script) to check style issues and code errors.

Working on Talos, I needed to find a way to find dead code on the codebase (the less code, the better!). I found a pretty good tool that helped me: vulture. This is a one shot tool – it can not be automated like flake8 as there is some false positives, but still running it once on an old codebase may be a big win to find and remove useless stuff.

Obviously it is easier to use on python programs – you will have to whitelist a lot of things if you run this on a python library that offers a public API.

If you want to seek and destoy dead code on your python program, give it a try!