autoindent different from manuall indenting

Question

We have a custom filetype at work which I use with a plugin i've written. There we have a construct like this:

\item some text.
  it is indented on level more than the \item tag
\item the next item should be indentend the same as the previous one

If i type this, I end with that:

\item abc
  \item abc

Because the indent is increased for the text. Now if I do a == on that line, it is aligned correctly which tells me, that my indent file works correctly. But I want to do this automatically. Since the \item tag is used a lot, it is laborious to do it manually all the time.

So my question, what is resposible for the automatic indent, how can my plugin fix that. I now that it won't be possible to give me an working solutions with the information I provide, but it should be sufficient to point me to the right direction.

Thanks

P.S. I know it looks like LateX, but due to other things used in the fileformat, I can't just use a LateX plugin. (And my Plugin has some other useful stuff).

Answer 1

You can use the indentkeys option, e.g. something like this:

setlocal indentkeys+==item

For LaTeX files, I use this (in vimtex):

setlocal indentkeys+=[,(,{,),},],\&,=item

See :h indentkeys for more info on the syntax.