"203 characters of unexpected output" error on activation

[jazzsequence]

The plugin generated 203 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.

probably some whitespace after a ?> somewhere

[afragen]

There aren't any closing ?> tags. I'm not seeing this and I have this plugin installed on many sites.

[jazzsequence]

Okay, well that was just a hunch. At any rate, I got this error on two different installs.

[afragen]

Can you do a quick test with all other plugins deactivated?

[jazzsequence]

Yep. Same thing. The number of characters is different depending on the install, but the error is the same.

[afragen]

Can you try this with no other plugins and TwentyTwelve theme? It may be something in your theme. I've checked again, I've intentionally not used ?> to avoid this. Is it a fatal error or because WP_DEBUG is true? Or plugin just not able to activate.

[jazzsequence]

I had Twentyfourteen active. Switched to Twentytwelve and still get it. No other plugins active.

WP_DEBUG is true but the plugin does activate, just after the unexpected output. There isn't a fatal error.

[afragen]

Can you download and install the plugin again. This is very strange.

[jazzsequence]

Same thing. Though it does go away if I set WP_DEBUG to false. Still, it shouldn't throw that message regardless. I did some testing and it doesn't seem to be related at all to whitespace. Tried a bunch of different things including adding a closing ?> to all the files and changing how the classes get called. There's something somewhere else that's throwing those extra characters.

[afragen]

The only other thing I found in googling that returns that error is an improper call, wrong path, to a core WP file. There's only one place I call plugins.php and I believe I've called it correctly.

Unfortunately unless we can find another with this issue. I can't reproduce it and I'm not sure how to correct it.

[jazzsequence]

No problem. It's your plugin, I'm just reporting an issue I got when I activated it. I'm just surprised you can't reproduce the error with WP_DEBUG on. I just installed it on a third WP install and got the same error.

[afragen]

I'll keep trying.

[afragen]

OK, I've just gotten back to my dev machine and I see the error. I'll let you know when I've got a fix. Thanks for being diligent.

[afragen]

@jazzsequence I think I've gotten all the errors out. Let me know if this is working for you. Thanks.

[jazzsequence]

That works but it throws an undefined index notice. I'll submit a pull request that fixes it in a minute.

[afragen]

Odd, I thought I fixed that too. I was having issues in committing. :-)