Sync multiple tabs using localStorage

[sidthekidder]

So this is the basic code to sync code editor value across multiple tabs. One caveat is that apparently when 'Code mode' is enabled, i.e. 'Block mode' is disabled, then realtime changes do not sync across tabs. (the text can't redraw itself like blocks do). So I set the Code mode to go into Block mode whenever it receives a localStorage update. Probably the performance is taking a hit - handler is executing twice every keystroke, so I want to improve it.
While the local-storage wrapper isn't so big, it is a new module (2 months old) and doesn't seem to add much benefit as local storage is well supported in browsers. Safari in incognito mode doesn't support it. ( http://ponyfoo.com/articles/cross-tab-communication )

[davidbau]

Neat that it works. Here is a list of some things to address:

• Only sync with changes on other tabs that are at exactly the same program (same user, same filename).
• Sync across modes. There's dropletEditor for block mode and just editor for text mode. Changing text in one more should sync up with blocks in the other mode.... maybe? Or maybe only if it actually parses? That's something to think about.
• Maintain "dirty" bits etc correctly. So if text changes, the "save" button gets shown at the right time.
• Consider syncing on every change, not only when the line-count changes.
• If you want to reduce syncing, consider using a timer to limit the frequency of changes sent to localStorage.

[sidthekidder]

I tried to address the last 3 points of your comments, they were insightful. Using setTimeout really coordinated well with syncing, but it seems to have failed some tests as a result.
I'll work on the first point (important one) and the tests too, but my exams are on so will be busy till the 13th.

[davidbau]

No problem. Looks like applications aren't due until March 27.

David

On Mon, Mar 9, 2015 at 9:05 AM, Siddhartha Sahai notifications@github.com
wrote:

I tried to address the last 3 points of your comments, they were
insightful. Using setTimeout really coordinated well with syncing problems,
but it seems to have failed some genuine tests.
I'll work on the first point (important one) and the tests too, but my
exams are on so will be busy till the 13th.

—
Reply to this email directly or view it on GitHub
#105 (comment).

[sidthekidder]

So added simple checks for matching user and file names (which get stored as json with the editor text when syncing).
Due to different editor on('change') code involving setTimeout, the Travis CI is failing. I don't understand the exact reason right now, apparently turtle.queue().length becomes 33 instead of 0 and the stop button doesn't show ($('#stop').length is 0). I guess I will have to examine setTimeout's usage closely to see why it changed those tests, and then also write a new one for testing sync.