ClassNotFound: no lexer for alias u'yaml=' found

[roll]

Hi,

Thanks for the very useful plugin.

We had spotless experience using it for a long period of time but we run into a very weird problem around a month ago.

It stopped to understand yaml syntax on Travis. It works locally 😕. Here is a build log:

https://travis-ci.org/frictionlessdata/website/builds/400004280

Could you please take a look?

cc @serahrono

[nixjdm]

I noticed that an earlier successful build used v0.1 of lektor-markdown-highlighter, but a new failure used v0.2. That's a clue perhaps, but, not much has changed here. That might be a red herring.

I was hoping to find a different pygments version, since I suspect this is more their problem, but its the same in both builds.

Did you only recently add yaml code blocks?

[nixjdm]

The error looks like just what you would get if you actually had ```yaml+= starting off a code block in markdown, but I don't see that in some of the error prone contents.lr files in your repo. And I doubt you'd have suddenly included so many anyway. I'm not sure what's causing this. Perhaps see if the pygments folk have an idea?

[nixjdm]

You could pass the verbose flag with lektor [server/build/deploy] -v, and that should get a traceback to be output. That may help.

[roll]

@nixjdm
Thank you very much for such a quick answer and help!

lektor ... -v was a key to find the issue. Because of the lektor-markdown-header-anchors plugin, the error was mentioned for every page. After anchors removal, I figured out that we dynamically pull some contents on the Travis build stage. And yes it uses yaml= and yaml=+ (probably thanks to hackmd.io). It was a pure fun to had 0 yaml mentions (ag yaml) in the codebase on some point of debugging and still getting this error 😖 😄

Thanks again. Fixed on our side.