Category Archives: Technology

The Joy of Coding (Ep. 20): Reviewin’ and Mystery Solvin’

After a two week hiatus, we’re back with Episode 20!

In this episode, I start off by demonstrating my new green screen1, and then dive right into reviewing some code to make the Lightweight Theme web installer work with e10s.

After that, I start investigating a mystery that my intern ran into a few days back, where for some reason, preloaded about:newtab pages were behaving really strangely when they were loaded in the content process. Strangely, as in, the pages wouldn’t do simple things, like reload when the user pressed the Reload button.

Something strange was afoot.

Do we solve the mystery? Do we figure out what’s going on? Do we find a solution? Tune in and find out!

Episode agenda.

References

Bug 653065 – Make the lightweight theme web installer ready for e10s
Bug 1181601 – Unable to receive messages from preloaded, remote newtab page – Notes
@mrrrgn hacks together a WebSocket server implementation in Go. To techno!

  1. Although throughout the video, the lag between the audio and the video gets worse and worse – sorry about that. I’ll see what I can do to fix that for next time. ↩

The Joy of Coding (Ep. 19): Cleaning up a patch

In this episode, I picked up a patch that another developer had been working on to try to drive it over the line. This was an interesting exercise in trying to take ownership and responsibility of something rather complex, in order to close a bug.

I also do some merging and conflict resolution with Mercurial in this episode.

Something else really cool happens during the latter half of this episode – I ask the audience for advice on how to clean up some state-machine transition logic in some code I was looking at. I was humming and hawing about different approaches, and put the question out to the folks watching: What would you do? And I got responses! 

More than one person contacted me either in IRC or over email and gave me suggestions on how to clean things up. I thought this was awesome, and I integrated a number of their solutions into the patch that I eventually put up for review.

Thanks so much to those folks for watching and contributing!

Episode agenda.

References

Bug 1096550 – Dragging tab from one window to another on different displays zooms in – Notes
Bug 863514 – Electrolysis: Make gesture support work – Notes

The Joy of Coding (Ep. 18): New Theme Song!

In this episode, I debuted The Joy of Coding’s new theme song, lovingly crafted by my good friend Barn Costello!1

Then I dove into fixing a new bug that allows e10s to continue running if the user is in safe mode. After that, we dove into an investigation on why click-to-play wasn’t working for a particular site.

Episode agenda.

References

  1. Shameless plug – Barn and I are in a band together. Here are some of our music videos. ↩

The Joy of Coding (Ep. 17): Frustrations in the Key of C++

In this episode, I gave a quick update on the OS X printing bug we’d been working on a for a few weeks (Spoiler alert – the patch got reviewed and landed!), and then dove into my new problem: getting performance profiles from subprocesses asynchronously.

And, I won’t lie to you, this is probably the most frustrating episode in the series so far. I really didn’t make much headway.

The way I want to solve this problem involves passing a DOM Promise back to the Javascript caller that resolves when all of the profiles have been gathered asynchronously.

If I were writing this in Javascript, it’d be a cinch. Creating, passing around, and resolving Promises is pretty straight-forward in that world.

But the Gecko profiler backend is written entirely in C++, and so that’s where I’d have to create the Promise.

A few weeks back, I posted a “Things I’ve learned this week” about how to create DOM Promises in C++. That’s all well and good, but creating the Promise is only half of the job. You have to resolve (or reject) the Promise in order for it to be useful at all.

The way I wanted to resolve the Promise involved parsing a JSON string and resolving with the resulting object.

That turned out to be a lot harder than I thought it’d be. Watch the video to see why. Suffice it to say, I spend a lot of it asking for help in IRC. It’s a 100% accurate demonstration of what I do when I’m lost, or can’t figure something out, and I need help.

Since I recorded this episode, I’ve figured out what I needed to do – I’ve posted a “Things I’ve learned this week” containing that information. Hopefully that’ll help somebody else in the future!

Oh – also, this episode has sound effects, courtesy of Wacky Morning DJ (which I demonstrated in last week’s episode).

Episode agenda.

References

Bug 1116188 – [e10s] Stop using sync messages for Gecko profiler – Notes

Things I’ve Learned This Week (May 25 – May 29, 2015)

MozReview will now create individual attachments for child commits

Up until recently, anytime you pushed a patch series to MozReview, a single attachment would be created on the bug associated with the push.

That single attachment would link to the “parent” or “root” review request, which contains the folded diff of all commits.

We noticed a lot of MozReview users were (rightfully) confused about this mapping from Bugzilla to MozReview. It was not at all obvious that Ship It on the parent review request would cause the attachment on Bugzilla to be r+’d. Consequently, reviewers used a number of workarounds, including, but not limited to:

  1. Manually setting the r+ or r- flags in Bugzilla for the MozReview attachments
  2. Marking Ship It on the child review requests, and letting the reviewee take care of setting the reviewer flags in the commit message
  3. Just writing “r+” in a MozReview comment

Anyhow, this model wasn’t great, and caused a lot of confusion.

So it’s changed! Now, when you push to MozReview, there’s one attachment created for every commit in the push. That means that when different reviewers are set for different commits, that’s reflected in the Bugzilla attachments, and when those reviewers mark “Ship It” on a child commit, that’s also reflected in an r+ on the associated Bugzilla attachment!

I think this makes quite a bit more sense. Hopefully you do too!

See gps’s blog post for the nitty gritty details, and some other cool MozReview announcements!